Lidl (UK) has Parkside inverter generator on offer next Thursday 31st May 2018

[Johnny B Good]

Seeing as how quiet this news group is of late, I thought I'd post a
copy of the above titled thread originally posted in uk.d-i-y on the off
chance that there may be UK based subscribers still monitoring
alt.energy.homepower.

However, since Lidl have expanded their operations into the USA in
recent years, this may prove of interest to the wider US centric group
monitoring from the sidelines so, if nothing else, here's my take on the
'Latest Offering' in inverter gensets from Lidl in the hope that it will
help relieve the boredom of monitoring this NG, an "activity" that's
perhaps best described as the business of "Watching Paint *Peel*". :-(

=========================================================================

/START-QUOTE/

The XYL returned from a quick shopping foray this afternoon with the
latest magazine showing next week's offers which included a "Golden Oldie"
first seen two years back. Said Golden Oldie (the PGI 1200 A1), presumably
being priced for nostalgic reasons, is on 'offer' at the original 129 quid
price (their version of "Rollback Pricing" I'm guessing).

Although remarkably cheap for an inverter genset even at the 30 quid
higher asking price than the later PGI 1200 B2 "Suitcase" generators they
were selling in the 2nd week of April this year, it has even more going
against it than the 99 quid B2 model which I'd assumed to be its
replacement and thus rendering the A1 model totally obsolete.

After checking out this video review on youtube:

<https://www.youtube.com/watch?v=oclB_Uj7KX8>

and taken another look at this one on the B2 model:

<https://www.youtube.com/watch?v=JTTGvjbY8_s>

which is worth checking out simply for the extremely informative
comments made by dean handley from ten months ago which would have saved
me so many return trips to finally track down a working PGI 1200 B2 some
seven weeks back, I have come to the conclusion that unless you want to
strip out the guts of the A1 and transplant them into a properly designed
enclosure of your own (whether portable "suitcase" or just a small brick
outhouse), or you simply want to use it for spares[1], I wouldn't bother
unless you're really desperate to get hold of a 1KVA pure sine wave
inverter generator having just missed out on April's bargain of the decade
in cheap inverter genset technology.

Having said that, it's still superior to a cheap open frame genset. Yes,
it may be almost as noisy but at least its 1KW of pure sine wave power can
be safely used with electronic kit and even old fashioned sine wave UPSes,
unlike normal generators using 'sophisticated' AVR control which will
grossly over-volt at the drop of a hat (leading current loads from a few
microfarad's worth of capacitance generally being all that's needed ime to
send a 2.8KVA 230vac generator going north of the 270vac mark!).

If you're looking for a cheap alternative to buying a few hundred quid's
worth of SLAs to boost the autonomy of a 1.5KVA or higher rated UPS by a
couple of hours, this could prove a more cost effective alternative,
especially as you can get a good 3 to 5 hours worth out of each gallon of
unleaded petroleum/gasoline you care to pour into its tank (5 to 7 hours
in the case of the PGI 1200 B2).

The only downside, of course, being the noise pollution if you don't
already have a suitable brick outhouse to minimise this and both secure
and run it safe from the CO poisoning and fire hazard risks presented by
such generators. In this regard, it's very little different to the 99 quid
PGI 1200 B2 Lidl were selling just a mere 7 weeks ago. For static use, the
only downside is that extra 30 quid hit on your bank balance.

Even so, it's a remarkably cheap way to buy into a 1KW standby source of
pure sine wave 50Hz 230vac power. Now that I've replaced all the GLS lamps
(bar the set of four 35W 12v halogen downlighters in the shower room) with
LED lamps, I can keep all the lights on along with the fridge,
the freezer, the 4K smart TV, my IT kit and the CH with a mere 1KW of
standby power. Admittedly, only at a pinch and by careful power management
but if ever the need for sustained emergency power ever arises, this is
just exactly what anyone running off emergency power would be having to do
anyway.

I'd have preferred a 2KW inverter genset but not only are the cheapest
alternatives some four or five times as pricey, they'll burn through
emergency fuel reserves faster as well even when only providing the same
amount of power as the smaller genset. Limited emergency power is better
than no emergency power at all and even if I do push the boat out on a
quieter 2KVA inverter genset at a later date, at just 99 quid, I can
afford hang onto the Lidl genset as an emergency backup to the 2KVA
emergency backup genset. You can never have too many emergency gensets
when the price is *so* right.

TBH, I'm quite amazed at the cheek of Lidl in trying to sell an inferior
version of the PGI 1200 B2 less than two months later and at an extra 30
quid to boot! Perhaps they're thinking that its "Retro Chic" cheap two
stroke portable genset looks are deserving of the extra 50 or 40 quid over
a more appropriate (IMHO) 80 or 90 quid price point.

Major points of difference between the A1 and the B2 models are:

The A1 uses a top mounted 4.2l pressed steel gravity feed tank prone to
leaking fuel during transportation. Fuel consumption rating at 2/3 power
output is 0.88l/hour from its 2.85hp 53.5cc engine (4.77 hours run time on
a tank of fuel). Considering the use of a gravity feed fuel system,
there's a surprising absence of a carburettor float bowl priming plunger
to assist cold starting.

The B2 uses a plastic (presumably shatter-proof) 4.5l side tank (which
reduces sloshing of its contents) feeding an engine vacuum powered fuel
lift pump[2]. Fuel consumption rating at 2/3 power output is 0.68l/hour
from its 2.04hp 53.5cc engine (6 1/2 hours run time on a tank of fuel).

The A1 is 200g lighter than the B2 (13Kg). Both produce the same total
sound power of 95dBW but the B2 claims to be 1.3dB quieter at the 1 metre
SPL test distance (80.2dBA).

Now that I have an actual class 2 SPL meter to test with, I'll be able
to confirm just how optimistic a claim this is for myself (give or take
1.5dB of metering error along with other environmental factors that make
such tests so less than 'scientific'). At least I'll be able to get base
line figures by which to gauge any attempts to quieten it.


[1] Afaict from pictures - unlike the potted inverter module in the B2,
two cermet trimmers do actually poke up out of the hard and shiny black
potting compound in the one used by the A1 making it amenable to adjusting
for manufacturer's calibration errors[3], assuming they haven't switched
over to using the same inverter part used by the B2 (probably not since
the A1 shown still only uses two LEDs to show status using blink codes for
normal/slight overload/full overload condition and "Goodnight Vienna"
whilst the B2 uses three LEDs).

[2] The only downside of using a fuel lift pump, aside from the extra
complexity over that of a simple gravity feed setup, is the need to spin
the engine over several times on the starter cord just to prime the fuel
line and the carburettor float bowl when starting from "Dry" (initial
commissioning run or else after a long lay up after letting the carb run
dry to minimise the risk of fuel gumming up the carburettor's jets during
periods of protracted storage).

In this case, it's best to crank the engine over leisurely 4 or 5 times
after turning the fuel feed on with the ignition still off and closing the
choke for the penultimate pull before turning the ignition on for a full
on pull of the cord to actually fire it up without needlessly wasting
energy on premature attempts to fire it up before there's even any fuel in
the carburettor float chamber.

Where more regular use (say every weekend) precludes any need to run the
carb float bowl dry, this won't be an issue. A single priming yank before
turning the ignition on and setting the choke should get it running on the
next pull of the starter cord.

[3] I discovered when testing with a 900W toaster and a bunch of 150W
incandescent lamps and a few other ses lamps of various wattages that the
inverter signals overloading at the 980W mark according to my digital watt
meter. I was a little disappointed at discovering this, especially in view
of the fact that it would cheerfully run a 1200W test load not for the
mere 5 seconds claimed but a full half minute every time before shutting
the inverter down.

I realise it's just possible that it's been calibrated to detect
overload at exactly 1001 watts and my watt meter is merely under reading
by 2% of the +/-3% allowance of its rated measurement tolerance. Still,
I'd have hoped they would have erred a little more on the positive side of
the tolerance range with their overload setting point, say 1050W before
sensing an overloaded state.

This is how I came to discover the complete absence of any means to
adjust the output voltage setting or the current overload point to correct
such a parsimonious setting. I guess I'll have to do some cross checking
with my other "Kill-A-Watt" meter and the analogue watt meter before
deciding whether to buy another PGI 1200 B2 the next time they're on offer
from Lidl to do a "Pick 'n' Mix" swap out to get the inverter genset I so
richly deserve.

/END-QUOTE/

==========================================================================

For the benefit of American readers, here in the UK we rarely experience
summertime heatwaves longer than a week so very few homes are equipped
with AC - it's simply not worth the investment unless it's part of a heat
pump based heating package. Most urban UK homes rely upon NG powered
central heating and domestic hot water systems which require less than 50
or 60 watts to maintain the controller panel, a zone valve or two, a
circulating pump and perhaps a small boiler flue purging fan.

The biggest compressor motor load in a UK home is likely to be a chest
freezer or fridge/freezer, typically less than 800W peak load, well
within the 1200W max (5 or 30 seconds) rating of the Parkside inverter
gensets mentioned above.

Also worth noting is the fact that urban mains voltage supplies which
serve over 80% of the UK's population, are largely laid underground and
have annual 'up times' in excess of 99.99%. The rest of the population in
the UK countryside (farmers and well paid city workers who commute or
otherwise telecommute or simply work from home) do have to endure the
problems of mains power carried over rural lines and so are generally a
little better prepared for outages typically measured in hours rather
than days. As per usual, some are better prepared than others.

Interest in backup emergency power is now increasing in proportion to
the increasing levels of Government incompetence in the provision of
winter time energy supply security, largely as a result of the folly of
'Green Power' investments made as a sop to those idiot 'Greens' who
believe that a few windmills and solar cells will provide all the energy
we'll need in preference to the only sane (and truly green) nuclear power
option.

All that and the fact that Honda no longer have a monopoly in inverter
genset technology means that we are seeing competitively priced inverter
gensets appearing in the market to serve the modest needs of homes with
electricity demands largely centred on sensitive electronic devices which
are not only susceptible to the poor quality of standard genset supplies
to begin with but which will also trigger such gensets into producing
destructive overvolting events. IOW, there's already an existing market
for mass produced cheap inverter gensets right here and right now.

I can only see those 2 and 3 KVA gensets with their "fancy" AVR going
the way of the Dodo as they prove themselves deadly to the task they were
designed for (they were never a good idea - the simple induction motor
converted to a "Poor Man's generator" with a dozen or so microfarad's
worth of run caps across the output were a safer bet for this application
anyway).

I can already see a situation where using such a conventional generator
won't even be a safe option just to literally keep the lights on in a
modern home full of cheap LED GLS lamps using simple capacitive dropper
ballasts for fear of over-volting to the capacitive load of the lighting
circuits alone! :-)

Even if for no other reason than this, the future for emergency gensets
depends on the use of inverter technology. It might be a relatively
expensive solution right now but, given the manufacturing cost reductions
of mass produced electronic hardware, it won't be too long before it
becomes cheaper to make an inverter genset than a 'standard' conventional
one.

Not only that but I can foresee the day when the recoil pull starter
will be relegated to backup emergency use only in favour of electric
start courtesy of a small 12v 7AH SLA (or more likely its more compact
and lighter Li-ion equivalent) and a brushless motor drive module
(ideally, a function built into the inverter module) to run the PM
alternator as a starter motor (no need for the extra weight and
mechanical complexity of a seperate starter motor when you can apply the
"Dynastart" principle in modern day brushless motor form).

From this, I can also foresee an integrated battery/inverter genset UPS
module to optimise the whole UPS with standby genset backup power
paradigm (the presence of battery backup would allow for improved stall-
free "eco-throttle" performance as an additional bonus). Since the PM
three phase alternators[1] generate either a nominal 200vdc for 120vac or
400vdc for 230/240vac inverter gensets, you'd either use 200 or 400 volt
battery packs in the genset/UPS combo or else use 12/24/36/48 volt
battery packs with a high efficiency DC-DC converter to provide the two
or four hundred volts required and accept the additional 1 or 2 percent
loss this would involve.

[1] Essentially a PM multi-pole rotor three phase high voltage version of
an automobile/truck alternator where the magnets are mounted on an outer
rotor which allows the alternator to be keyed onto the engine shaft to do
double duty as the engine's flywheel, thus neatly saving unnecessary
weight and space. It's the reason why they can be made so lightweight and
compact. The inverter module is effectively a pair of back to back class
D power amplifiers, designed to be powered off a 200 or 400 volt DC rail,
driven from a 50 or 60 Hz pure sine tone reference and using the much
lower sampling rate of circa 5KHz to improve efficiency beyond the
typical Hi-Fi sampling rate of 48KHz used in standard class D audio amps.

The 200/400 dc voltage from the alternator is controlled by engine speed
alone via stepper motor control of the carburettor throttle mediated by
the microprocessor in the inverter module which compensates for varying
electrical demand on the inverter's output terminals both for volt drop
due to resistance in the alternator windings and to vary the throttle to
control engine torque according to the current demanded by the electrical
load. All that's required by way of alternator voltage control is that it
stays within the relatively wide range of 350 to 420vdc in the case of a
240vac inverter output (or half of those voltages for a 120vac inverter
case).

Given enough time between now and Armageddon, I've no doubt we'll see
water cooled fuel injected engine modules being used in the later more
compact, quieter and even more fuel efficient portable inverter gensets
with built in Li-ion battery backup and automatic electric start. :-)

--
Johnny B Good

[Johnny B Good]

Well, did anyone here in the UK check these out at their local Lidl
store? :-)

--
Johnny B Good

[dolmen]

Hi there I watched the vids, thanks for the links and decided against the A1 and am waiting in the chance that the B2 option will come up again. It certainly seems like a much better option all things considered.

[Johnny B Good]

On Sat, 02 Jun 2018 02:32:51 -0700, dolmen wrote:

> On Saturday, May 26, 2018 at 4:24:17 PM UTC+1, Johnny B Good wrote:

====snip====

=====snippage of my take on the merits of inverter gensets====

>
> Hi there I watched the vids, thanks for the links and decided against
> the A1 and am waiting in the chance that the B2 option will come up
> again. It certainly seems like a much better option all things
> considered.

Thanks for the follow up. I was beginning to think I was the only UK
citizen still subbed to this NG. :-)

The only problem with doing that is you could be left waiting for quite
a long time before the B2 gets put back "On Offer" (or it might reappear
next month - who can tell with Lidl's (and, for that matter, Aldi's)
kakamaimee retailing strategy?) so you might start regretting that
decision some six months down the line.

It's worth keeping in mind just how much more expensive the alternatives
available in this segment of the UK inverter genset market are. A quick
search using duckduckgo located this open frame HortiPower 1800/2000W
inverter genset at Amazon, currently on sale for a mere £249.00

<https://preview.tinyurl.com/yce6fbct>

That's an unusually cheap price for a 1.8KW rated inverter generator but
I've no idea what their quality is like. They quote the 7 metre SPL
rating which makes it around 16dB quieter compared to the 1 metre SPL
figure quoted by Parkside inverter gensets. Once you've added that
missing 16 dB this gets you an 81dBA SPL@1mtr to directly compare the
two. Considering the absence of cosmetic panels, this rather highlights
what the reviewer was saying about the A1.

If you're looking for a less marginally specified output power genset,
this could be a better alternative (but you'd be spending an extra 120
quid on a machine that burns a litre of fuel an hour when loaded to 70%
(1260W) versus 0.88 litre per hour at 75% of load (750W) for the A1 or
0.68 litre an hour in the case of the B2) and you'd be dealing with a
company based out of Peterborough in Cambridgeshire run by a person of,
it would appear, Polish extraction.

That's just fine and dandy if you happen to live in and around
Peterborough but a bit of a pain for the rest of us who have to wait on
delivery by Amazon or, worse still, deal with returning faulty goods,
guarantee or no guarantee.

I only mentioned that HortiPower unit because it's the first time I've
seen an alternative 1 to 2 KVA rated inverter genset in the UK below the
300 quid mark. The prices for inverter gensets available from walk in
stores such as MachineMart, Toolstation and Screwfix typically start at
£190 for a 700/780W rated inverter genset <https://tinyurl.com/ycfm8vjo>
and carry on upwards of 280 quid for a 1.2/1.5KW Impax and 400 quid for
the 2.2/2.5KW Impax inverter gensets (Screwfix prices). What the extra
money might buy you in this case is maybe a 2dB reduction in noise
pollution levels (Oh, and a 12v charging lead and shorter run times on a
tank of petroleum/gasoline).

My derogatory remarks about the A1 were made from a position of great
strength. I'd already acquired the slightly superior version at the
bargain of the decade price of 99 quid. :-) It won't matter so much to me
if the B2 models never reappear but if and when they do, I'll get my
chance to compare the overload set points and swap out the inverter
module if the second unit is on a more generous overload trip point
setting.

With the exception of the B2 model, compared to every other 1000/1200W
inverter genset model currently available in the UK, there's nothing
anywhere near as cheap, even at that elevated £129.00 price point.

There's a massive price premium on truly quiet suitcase inverter gensets
(12 to 18dB quieter) suitable for use on camp sites. The Honda units
typically adding an extra 800 quid onto the price of the Parkside units.
Those other Impax models mentioned above are, at best, just another 2 or
3dB quieter and this is typical of most of the competing models in the
two to four hundred quid price bracket.

BTW, talking about SPL figures, I took the opportunity yesterday
afternoon to run another test of mine using a 240v 900W toaster as a 780W
(230v) test load to get some SPL readings. This time I took the trouble
to mentally take note of the actual readings at the 1 metre mark for idle
at eco and normal settings as well as on a 780W load.

I'd stood the generator on a hard concrete surface alongside of the
patio table (so no benefit from soft grassy soil to knock a dB or two off
the 'hard standing' readings) where I had the toaster and a couple of
plug-in energy monitors[1] plugged into a short 4 way mains extension
lead set up to toast a couple of slices for my 7 year old twin
granddaughters to sample the delights of "Generator Toast".

From the starboard side panel, I got readings of 79 and 88 dBA
respectively for eco idle and 780W loaded (whether in eco-idle mode or
not) whilst the figures for the exhaust (stern) end were, as expected,
about another 2 or 3 dB higher. I didn't bother stepping back another 20
feet to get 7 metre SPL figures since there was too much 'clutter' to get
any meaningful 'free space' readings.

I was a little surprised that the 780W load didn't boost the non eco-
idle speed since earlier tests with 960 to 1200 watt loads had
demonstrated a slight but definite speed increase. I guess the 780W load
wasn't quite enough to justify any further speed increase, merely a wider
(and louder) throttle setting to increase the engine torque required to
balance the alternator drag. I'd expect the SPL to go up another dB on
the 780W load figure when generating the full 1KW's worth of maximum
sustainable output (in my case, 980W[2] just before it starts the 30
second timer[3] to 'overload shutdown')

Since the Parkside generator specs included a tolerance error (K factor)
of 1.2dB for their claimed 1 metre SPL dBA figures and my class 2 SPL
meter could be out by +/- another 1.5dB anyway, those readings seem an
entirely reasonable match to the specifications which I had naturally
assumed to have been determined with the generator running in its
quietest mode, unloaded eco-idle enabled.

The dBA SPL claims for all these gensets will always be for the quietest
mode of operation and you can likewise expect a similar 10dB boost when
running at maximum sustainable output (but don't forget the 16dB
difference between 1 metre and 7 metre (23 feet) referenced SPL figures).

Don't assign too much meaning to the expression "quiet" in the
manufacturers' description copy, written by PR types educated in the fine
art of "Lying by omission" where the justification for such a statement
can be as slight as the product being a mere 1 or 2 dB quieter than a
standard open frame generator of comparable output. Ignore such wishy
washy statements as "Quiet", "Quieter", "Quietest yet" and take care of
the 1 and 7 metre SPL standards' 16dB difference when looking at any
actual numbers they may offer in their "Specification" sheet.

Except for notably quiet exceptions from Honda (and a few other brands -
Honda no longer hold a monopoly in "Very Quiet"), you can assume a 'ball
park' 1 metre SPL figure of 96dBA safe in the knowledge that you're
unlikely to be more than 2 or 3 dB out on the actual SPL figures.

[1] I was using one to monitor voltage and the other the load wattage.

[2] According to one of my plug-in energy monitors, the one that matches
very closely my trusty Metrawatt analogue watt meter as opposed to the
230vac version of a Kill-A-Watt meter which under-reads by comparison
(and which I'd relegated to monitoring the voltage during this test).

[3] The specifications for both the A1 and the B2 models mention a 5
seconds limit on the 1200W surge rating. However, it turns out that the B2
model will sustain such an overload for a whole 30 seconds before
tripping the inverter out, necessitating a reset which, unconscionably
requires the engine to be stopped rather than by a reset button which
would allow the engine to keep running to save the ritual of another pull
start.

Mind you, this is probably for the best since in practice this means the
inverter will get a chance to cool down any thermally stressed parts
before the user gets another chance to abuse it[4]. This can be a pain if
you're running close to the limit without a UPS in line to protect more
critical loads such as desktop PCs and NAS boxes which don't take kindly
to having the rug pulled out from under them.

Even with a UPS, there's still some pain since you have to nip out to
attend the generator. However, that said, restarting is a doddle since it
will be warm and primed ready to go on the first confident pull of the
starter cord. even if you've left it half an hour it will still be nice
and warm since the engine carries on running, leaving you to manually
switch it off when you're ready to restart it (see note[4])

[4] Unless they stand ready to switch the engine off and then switch it
back on just before it comes to a complete standstill which, if timed
exactly right (it's quite critical is the timing!), will reduce the
alternator output voltage sufficiently to initiate an inverter reset
whilst there is still enough inertial energy to let the engine pick back
up on turning the engine switch back on. No need to ask me how I know
this, I'll tell you - I simply tried this trick a few times before I
succeeded in resetting the inverter module without the engine stalling
out. :-)

It's a useful trick since it saves needless wear and tear on the starter
cord and you can still give the inverter module time to recover by simply
waiting a minute or two before cycling the engine switch. Incidentally,
there's no need to unplug the load before firing it up unless you have
loads with heavy startup current demands that can take it well beyond its
1200W limit (or over its 1000W - 980W in my case) limit for more than 30
seconds).

The only item that didn't like the resulting soft start being the 230vac
Kill-A-Watt meter which requires a more rapid voltage increase to reset
itself - i.e being plugged into an already live socket or the socket
switch turned from off to on. Apropos of which, other things that might
not take kindly to a soft start could be fridge and freezer compressor
motors.

The freezer you'd only plug in once a day when the load will be
minimised or even totally shed so as to chill the cabinet on the "Rapid
Freeze" button to prepare it for its next round of doing without
electricity for a bit. Freezers can keep their contents safely frozen
during 24/48 hour power cuts if they aren't being accessed every half
hour of the day so using the "Rapid Freeze" button to reduce the
temperature below normal is an effective way to timeshare the generator's
energy output to minimise overloading events.

Modern fridge compressors, I believe, only use 35 to 60 watts when
running although they may demand 3 to 6 times that for a few seconds when
starting up. However, I haven't tested this with our own fridge so I
can't verify this from actual experience.

If you happen to have a really modern fridge/freezer using a linear
compressor, you won't suffer the 'compressor startup surge' effect which
simplifies the issue of running it from inverter generator power somewhat.

--
Johnny B Good

[danny burstein]

In <z_eOC.336559$B36.1...@fx22.am4> Johnny B Good <johnny...@invalid.ntlworld.com> writes:

[snip]

> For the benefit of American readers, here in the UK we rarely experience
>summertime heatwaves longer than a week so very few homes are equipped
>with AC - it's simply not worth the investment unless it's part of a heat
>pump based heating package. Most urban UK homes rely upon NG powered
>central heating and domestic hot water systems which require less than 50
>or 60 watts to maintain the controller panel, a zone valve or two, a
>circulating pump and perhaps a small boiler flue purging fan.

> The biggest compressor motor load in a UK home is likely to be a chest
>freezer or fridge/freezer, typically less than 800W peak load, well
>within the 1200W max (5 or 30 seconds) rating of the Parkside inverter
>gensets mentioned above.

Maybe, maybe not. There are all sorts of "invisible", for want of
a better term, electrical loads that are big enough to be a
potential problem

a: in the US, the common standard way natural gas stove/oven
combinations operate these days is that the stove top is lit
by an electrcial spark ignitor. Noisy, but low current and
it shuts off after a couple of seconds.
HOWEVER
the OVEN is different. It's very common for that gas to get
ignited by an electrical glow plate, which
1: pulls 500 watts
and
2: keeps drawing all that power the entire time the oven's
gas flame is lit.

b: refrigerator freezers may only pull 100 to 200 watts these
days (often even less),
BUT
when they go into auto-defrost mode, the heater can easily
pull 500 watts.

So you really need to check for these issues.

> Not only that but I can foresee the day when the recoil pull starter
>will be relegated to backup emergency use only in favour of electric
>start courtesy of a small 12v 7AH SLA (or more likely its more compact
>and lighter Li-ion equivalent) and a brushless motor drive module
>(ideally, a function built into the inverter module) to run the PM
>alternator as a starter motor (no need for the extra weight and
>mechanical complexity of a seperate starter motor when you can apply the
>"Dynastart" principle in modern day brushless motor form).

What would also be nice is for other manufacturers to pick up
a design Yamaha used to offer. They had a line of electric (battery)
start generators which... kept the battery in the circuit.

This allowed (numbers for illustration) their 2 kw generator
to, for a short period (as in when your well pump started)
provide 3 kw.

Hence you could (again, numbers for illustration) measure
out 1.5 kw in peak demand and get a 2 kw unit, and not worry
about the extra power requirments when motors kicked in.

Otherwise, you might have needed the extra capacity of
a larger, more expensive, and less fuel efficien 5 kw unit.


--
_____________________________________________________
Knowledge may be power, but communications is the key
dan...@panix.com
[to foil spammers, my address has been double rot-13 encoded]

[dolmen]

On Saturday, May 26, 2018 at 4:24:17 PM UTC+1, Johnny B Good wrote

> Given enough time between now and Armageddon, I've no doubt we'll see
> water cooled fuel injected engine modules being used in the later more
> compact, quieter and even more fuel efficient portable inverter gensets
> with built in Li-ion battery backup and automatic electric start. :-)
>
> --
> Johnny B Good

Thanks for the detailed reply, I'm in no way educated in the workings of these, but rely on kind folks like you on the web sharing their experience and knowledge to inform me, then I makes my choice. I do have a larger petrol open frame chinese type generator, it works but not so refined. At least I'm not stuck when the power does go off, and it drives everything freezers, oil burner, pumps and lights etc However the inverter one caught my eye but never managed to get one and the much higher prices quoted for the red ones leave a bad taste for something that is going to sit for months on end!
Changing the subject slightly, I was considering a Li-ion battery bank and 900W solar but having contacted 4 Companies not one was interested! and because its rather a lot of money I wasn't convinced I knew enough to DIY. I do have the generator changeover switch so a battery bank may well work with the generator plus add solar at anytime. Run the generator to charge up the batteries and run quietly in the evenings.

[Johnny B Good]

On Sun, 03 Jun 2018 03:02:34 +0000, danny burstein wrote:

> In <z_eOC.336559$B36.1...@fx22.am4> Johnny B Good
> <johnny...@invalid.ntlworld.com> writes:
>
> [snip]
>> For the benefit of American readers, here in the UK we rarely
>> experience
>>summertime heatwaves longer than a week so very few homes are equipped
>>with AC - it's simply not worth the investment unless it's part of a
>>heat pump based heating package. Most urban UK homes rely upon NG
>>powered central heating and domestic hot water systems which require
>>less than 50 or 60 watts to maintain the controller panel, a zone valve
>>or two, a circulating pump and perhaps a small boiler flue purging fan.
>
>> The biggest compressor motor load in a UK home is likely to be a chest
>>freezer or fridge/freezer, typically less than 800W peak load, well
>>within the 1200W max (5 or 30 seconds) rating of the Parkside inverter
>>gensets mentioned above.
>
> Maybe, maybe not. There are all sorts of "invisible", for want of a

"hidden" I think is the word you were looking for. :-)

> better term, electrical loads that are big enough to be a potential
> problem
>
> a: in the US, the common standard way natural gas stove/oven
> combinations operate these days is that the stove top is lit by an
> electrcial spark ignitor. Noisy, but low current and it shuts off after
> a couple of seconds.

We have a gas hob which uses a mains powered spark igniter just like
that. That's been a common feature of gas hobs in the UK for the past 20
years or more. An alternative to that is a battery powered spark igniter
which our previous gas hob, purchased some 25 years ago, used (for the
first couple of years anyway until it failed). A new battery didn't fix
it so we resorted to the old fashioned way of lighting the burners until
we replaced it some two or three years ago.

> HOWEVER
> the OVEN is different. It's very common for that gas to get ignited by
> an electrical glow plate, which
> 1: pulls 500 watts
> and
> 2: keeps drawing all that power the entire time the oven's gas flame
> is lit.

That's an interesting use of electricity to supplement the heat
contribution to a gas oven. I suppose it has the merit of eliminating the
risk of a flame blow-out and the potential for a gas explosion. Since we
moved house some 35 years ago, we've only had all electric (built in)
ovens. I'm not sure what the practice is with gas ovens in the UK since
they're not as common as they used to be back in the days of free
standing gas cookers.

>
> b: refrigerator freezers may only pull 100 to 200 watts these
> days (often even less),
> BUT
> when they go into auto-defrost mode, the heater can easily pull 500
> watts.
>
> So you really need to check for these issues.

Very good points raised, particularly in regard of auto-defrosting
heater elements in fridges and freezers. It's rather like overlooking the
reason for not powering your 25 watt (average power consumption) laser
printer via the protected outlets on a UPS due to the 500W fast warm up
drum heater that only draws power for 5% of the time to maintain drum
temperature after the initial half minute run up. It may only average 25
watts but it's those 2 or 3 second bursts of 500W that'll trip your 450W
700VA UPS out every time.

We've got a seperate under the counter fridge and chest freezer, neither
of which is blessed (cursed) with such defrost heaters. Modern fridges, I
understand, usually work smarter rather than harder with their automatic
defrost feature.

Since the ideal temperature in a fridge is between 5 and 8 deg C (41 to
46.4 deg F), the (or part of the) cold plate can be placed low down at
the back just above moulded gutters that lead to a drain hole which drips
the condensate onto the can of the compressor, the heat of which
evaporates it back to the atmosphere from whence it came.

Eventually, that cold spot humidity collector will frost up enough to
warrant a proper defrost by hand operation but this is a small price to
pay to eliminate a counter-productive heating element inside something
that's meant to be kept cool at *all* times.

Freezers otoh, are a different kettle of fish in regard of keeping frost
build up at bay, unlike a fridge which isn't meant to even drop as low as
0 deg C (32 deg F), they have to contend with cabinet temperatures
typically around the -18 deg C mark (0 deg F) so frost build up is
inevitable, requiring either manual intervention or else a heating based
automatic defrost cycle.

If you're "cheap" like me, you won't tolerate the expense (both capital
and running costs) of a combined fridge-freezer with its automated
defrost cycles, opting instead for seperate fridge and the classic chest
freezer guaranteed to not have any such encumbrances.

I don't believe it's practical to incorporate automatic defrost in a
chest freezer anyway (BICBW so please feel free to correct me if needs
be), besides which, the chest freezer format remains a popular option
because of its improved efficiency at keeping its contents frozen for
long periods of time even when the lid is opened up two or three times a
day to add to or retrieve from its contents.

A top opening lid offers minimum disturbance to the freezing cold air
within, especially if opened and closed slowly, unlike the vertically
hung door of a fridge-freezer where it's a race to add to or retrieve
from its contents before all the freezing cold air has dropped onto the
kitchen floor to be replaced with warm air. The conventional domestic
fridge suffers this problem too but we're only dealing with chilled air
rather than the more expensively produced freezing cold air of a freezer
so the price of convenience in this case is far better value.

I guess, if you're using an older fridge freezer instead of a seperate
chest freezer and fridge, you're not going to be dicking around with a
cheap 1KW/1.2KW peak @ unity power factor inverter genset like the
Parkside model I've been discussing here.

Otoh, if you've recently pushed the boat out on an even higher
efficiency "Analogue Compressor" fridge-freezer (in truth an inverter VFD
compressor type) which doesn't suffer from the compressor startup surge
loading effect, a cheap inverter genset might do the trick, assuming a
smarter auto-defrosting algorithm that doesn't involve half kilowatt
heaters to brute force the defrost cycle.

I'm not sure about this but you'd think if the manufacturers were going
to the expense of a digital VFD setup, they'd have put more thought into
designing a less brute force approach to the question of auto-defrost so
as not to compromise their A+++ ratings.

Anyway, as you pointed out, it's the hidden vampire loads you need to be
aware of when trying to size an emergency power generator for home use,
an issue I'd overlooked simply because our fridge and chest freezer are
only cursed by the compressor startup surge issue and the oven is all
electric so totally out of the running. The gas hob will likewise not be
part of the emergency power load since the burners can still be lit the
old fashioned way just like any such gas hob (the flame out gas cut-off
valves are self powered from the thermo-couple sensor current making them
independent of a mains voltage supply anyway).

>
>> Not only that but I can foresee the day when the recoil pull starter
>>will be relegated to backup emergency use only in favour of electric
>>start courtesy of a small 12v 7AH SLA (or more likely its more compact
>>and lighter Li-ion equivalent) and a brushless motor drive module
>>(ideally, a function built into the inverter module) to run the PM
>>alternator as a starter motor (no need for the extra weight and
>>mechanical complexity of a seperate starter motor when you can apply the
>>"Dynastart" principle in modern day brushless motor form).
>
> What would also be nice is for other manufacturers to pick up a design
> Yamaha used to offer. They had a line of electric (battery)
> start generators which... kept the battery in the circuit.
>
> This allowed (numbers for illustration) their 2 kw generator to, for a
> short period (as in when your well pump started)
> provide 3 kw.
>
> Hence you could (again, numbers for illustration) measure out 1.5 kw in
> peak demand and get a 2 kw unit, and not worry about the extra power
> requirments when motors kicked in.
>
> Otherwise, you might have needed the extra capacity of a larger, more
> expensive, and less fuel efficien 5 kw unit.

Good for Yamaha for "thinking (just a tiny bit[1]) out of the box".
Although none of that aught to be "Patentable" (it's just an obvious use
of existing technology after all), I wouldn't mind betting they got their
patent lawyers to give it the good old "College Try" to, if not stop the
competition dead in its tracks, then at least slow it down a little. The
competition might be contesting or working around Yamaha's patents as we
discuss the matter.

BTW, well pumps are the very rare exception in this ever so green and
pleasant land of ours, here in Blighty. That's yet another difficult
startup load most UK citizens rarely have to include in their emergency
back up power plans for the relatively small proportion of the population
that have actually given it any thought at all. :-)

Britain is such a small and self contained kingdom compared to the US,
that it would take a peculiarly extreme disaster to cut off water
supplies on any significant scale. In the event of nuclear Armageddon
most everyone's problems will likely be over in a flash unlike in the
remoter parts of the US where Survivalism does at least make some sense.

That's not to say the far northern parts of Scotland, in particular the
northern isles, would lend some credibility to the Survivalist philosophy
but that's an even tinier fraction of the UK population compared to the
US case where Survivalism might pay its promised dividend[2].

[1] If I can work out how to apply the existing switching based voltage
converter and VFD technologies to get the most utility from a basic ICE
with integrated PM three phase multi-pole flywheel alternator machine,
then it can hardly be "patentable"... surely?

[2] Just imagine it! A world swept clean of a 7 billion surplus of the
"Chattering Masses" onto which so much of the planet's resources have
been squandered. Now *that* would be something worth surviving for, a
world where meeting a fellow human being could be considered a rare and
welcome treat rather than the all too commonplace irritation it can often
be today.

Don't get me wrong. I'm not advocating the mass culling of 99.9% of
Humanity, who like 99.999% of Humanity, myself included, have sleepwalked
into this predicament of overpopulation that now threatens our very
existence through making unsustainable demands on the planet's resources,
since I'm likely to be in that 99.9% group destined to make way for the
hopefully grateful 0.01% of Humanity that does survive the seemingly
inevitable nuclear Armageddon.

From what I see in the news of world events, particularly political
events where the politicians (and electorate) seem to getting stupider by
the hour, I can well imagine a real "Doomsday Clock" in various offices
of "The Golden Rulers" dispersed around the several underground nuclear
bunker complexes, showing not the the last few seconds representation of
all human history to date but actual years and months left to go (perhaps
just months if recent events are any guide) before the puppet strings are
to be pulled to initiate the final nuclear Armageddon to make way for a
new hope for Humanity to have another go at getting it right this time.

Like the published doomsday clock, I can imagine it being 'tweaked'
every now and again to take account of delays in the many and varied
preparations towards the actual doomsday event.

I know this seems like yet another conspiracy theory. It can certainly
be viewed that way but, in all honesty, this is my way of hanging onto
the hope that there is purpose behind the seemingly inevitable
destruction of human civilisation rather than it just being the result of
pure dumb stupidity alone with no other purpose than MAD.

Quite frankly, I'd rather my assessment was right rather than merely a
comforting delusion. Regardless of events, death awaits us all anyway so
I might as well entertain myself with my best guess at what's really
going on as we seemingly edge closer and closer to our ultimate demise.

It's a viewpoint not unlike that of a famous philosopher/scientist who,
when asked if he believed in the existence of God, explained that his
belief in God was in the nature of a bet on his existence being true in
which case he'd reap the reward of everlasting life in heaven rather than
merely have his soul extinguished at death if he'd chosen to deny God's
existence and it turned out to be true - if his belief in the existence
in God proved a false one, he'd be no worse off anyway. Unfortunately, I
can't recall which famous philosopher/scientist it was who said this
(also, I've had to paraphrase the actual quote).

--
Johnny B Good

[Jim Wilkins]

"dolmen" <dob...@gmail.com> wrote in message
news:e367f0df-71fb-42de...@googlegroups.com...
...

Changing the subject slightly, I was considering a Li-ion battery bank
and 900W solar but having contacted 4 Companies not one was
interested! and because its rather a lot of money I wasn't convinced I
knew enough to DIY. I do have the generator changeover switch so a
battery bank may well work with the generator plus add solar at
anytime. Run the generator to charge up the batteries and run quietly
in the evenings.

----------------------------

The problem I encountered with my solar battery system was the high
idle power of pure-sine inverters suited to 120VAC refrigerators. The
inverter I have runs continuously and consumes as much overall from
the battery as my small fridge. It needs to be sized for the starting
surge, which is 12A on mine.

I'm testing a Chinese Alpicool DC-powered fridge/freezer which can
operate directly on 12V or 24V. It has its own set of quirks to deal
with but so far it doubles the battery run time when it's the only
load, and may permit a smaller and more efficient modified sine
inverter for non-motor loads in the daytime.

-jsw

[Johnny B Good]

On Sun, 03 Jun 2018 03:08:23 -0700, dolmen wrote:

> On Saturday, May 26, 2018 at 4:24:17 PM UTC+1, Johnny B Good wrote
>
>> Given enough time between now and Armageddon, I've no doubt we'll see
>> water cooled fuel injected engine modules being used in the later more
>> compact, quieter and even more fuel efficient portable inverter gensets
>> with built in Li-ion battery backup and automatic electric start. :-)
>>
>> --
>> Johnny B Good
>
> Thanks for the detailed reply, I'm in no way educated in the workings of
> these, but rely on kind folks like you on the web sharing their
> experience and knowledge to inform me, then I makes my choice. I do have
> a larger petrol open frame chinese type generator, it works but not so
> refined. At least I'm not stuck when the power does go off, and it
> drives everything freezers, oil burner, pumps and lights etc However the
> inverter one caught my eye but never managed to get one and the much
> higher prices quoted for the red ones leave a bad taste for something
> that is going to sit for months on end!

I know where you're coming from. Sheesh! An extra 800 quid just to
upgrade that 99 quid Parkside inverter genset I'd bought back in April to
a quieter version. If you're going to use it for emergency home power,
there are much cheaper ways to deal with the noise pollution[1]. Even the
A1 version that went on sale in UK Lidl stores last Thursday are still
one hell of a bargain at 129 quid versus the 280 quid 1200/1500W Impaq
models available from local Screwfix stores in the UK.

> Changing the subject slightly, I was considering a Li-ion battery bank
> and 900W solar but having contacted 4 Companies not one was interested!
> and because its rather a lot of money I wasn't convinced I knew enough
> to DIY. I do have the generator changeover switch so a battery bank may
> well work with the generator plus add solar at anytime. Run the
> generator to charge up the batteries and run quietly in the evenings.

I'm afraid I can't offer any practical advice regarding Li-ion battery
banks and chargers. My experience is more to do with good old fashioned
lead acid battery setups, mainly to do with various UPSes I've used over
the past 20 years or so.

What I can say, if you're thinking of using lead acid batteries with a
1KW or higher output inverter, is not to make the mistake I've seen in
many a youtube vid of using 12v inverters with a bank or two's worth of
forklift truck batteries.

If you're going to buy a 1 or 2 KW inverter choose a 24v or, better yet,
a 48v inverter setup which will save a small fortune in heavy duty
battery cables as well as reduce I squared R losses. Instead of circa
100A per KW of grid voltage output from a 12v battery (which is starter
cranking amps territory), a 48v battery will reduce this to just under 25
amps per KW of grid voltage power.

[1] There are plenty of youtube vids demonstrating the many ways of how
*not* to create quiet generator enclosures by folk who have totally
underestimated the problems of containing the noise pollution in a
plastic or wooden box breached by the relatively large holes required to
vent the enclosure to prevent the generator from cooking itself with (and
choking on) its own exhaust fumes.

A suitcase styled inverter generator out of necessity, provides its own
forced air ventilation to both cool the inverter module and the engine
and, in particular, the exhaust muffler to prevent it melting the plastic
casing.

Installed into a properly designed brick enclosure, it shouldn't need
any additional fan cooling if the sound absorbent lined ventilation tunnel
[2] for the exhaust is sized a little larger in CSA to that of the
exhaust vent that typically encloses the muffler's exhaust pipe. A few
inches of separation between the rear of the generator and the mouth of
the exhaust vent needs to be provided to utilise the venturi effect to
draw additional air past the sides of the generator to prevent heat build
up within the enclosure.

Obviously a similarly sized intake vent will be needed at the opposite
end, with a suitably labyrinthine pathway to the intake end of the
generator with blocks of sound absorbent material strategically placed so
as not to choke down the intake path.

Also, just like the exhaust end there needs to be clearance for the
extra air drawn in by the exhaust venturi effect to work its magic of
removing any residual heat build up from conducted and radiated heat that
would otherwise normally escape direct to the atmosphere. I doesn't need
much of an airflow to achieve this goal in the case of suitcase styled
inverter gensets compared to a typical open framed generator.

In any case, it would only be prudent to monitor the interior air
temperature to be verify that there's no overheating risk to the petrol/
gas tank contents or the generator itself. This should be done as part of
the commissioning tests at the very least.

Depending on the results of those tests, you can decide whether or not
there's any need to permanently monitor the enclosure temperature to
provide an overheat alarm which could be used to start a timer to shut
the generator off automatically for your own peace of mind.

[2] Most of which can consist of a vertical brick chimney (say 6 foot or
so tall) to take advantage of the exhaust heat energy to generate an
additional draw assist to the ventilation airflow and to direct the
residual noise skywards and away from neighbouring properties.

Any weatherproofing measures against rain ingress should ideally be
effectively sonically transparent to avoid deflecting residual exhaust
noise back towards your immediate neighbours. This trick of simply
deflecting the noise skywards can account for a 6dB reduction in the
horizontal plane so it's worth trying to avoid spoiling this effect with
a standard rain proofing cowl if you can.

--
Johnny B Good

[ads]

Most commercial suppliers are not interested in relatively small
installations because the pricing they can give on big systems falls
apart below a couple of kw. There's similar setup time and labor for
a few solar panels as for 4 times that many as well as the wiring so
the costs for small solar don't work out.

I'm handy at finding good used and recycled gear, as well as finding
bargains in electronic equipoment. I put together a 12 volt, 540AH
(6480WH) battery bank with two 2000 watt pure sine wave (PSW)
inverters, a 500 watt PSW inverter, two 30 amp MPPT charge
controllers, 900 watts of solar panels and all the interconnect
wiring, fuses, circuit breakers and monitoring equipment for $2100US.
The electronics were shipped but the batteries and solar panels were
sourced locally (no shipping, just gas for my truck). The solar
panels are not yet permanently mounted (still working out which of 3
possible mounting locations is the best location).

I do have 25 amps of precisely controlled battery charging equipment
that can be powered by a gasoline generator (NOT the $30 cheapie
charger from the auto parts store). An hour of that charging provides
1 to 4 hours of runtime from the battery bank, depending on the season
(more heat and light needed in winter and less sun available for solar
charging).

My design goal was "Wait until daylight" power so I would not be
setting up the gas gen in the dark or during a thunderstorm because
most of our outages are less than 16 hours. Depending on the season,
the system provides 10 to 20 hours of limited power. The design meets
my goal and I learned a great deal about solar power.

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[dolmen]

On Sunday, June 3, 2018 at 8:37:48 PM UTC+1, Jim Wilkins wrote:

> The problem I encountered with my solar battery system was the high
> idle power of pure-sine inverters suited to 120VAC refrigerators. The
> inverter I have runs continuously and consumes as much overall from
> the battery as my small fridge. It needs to be sized for the starting
> surge, which is 12A on mine.
>
> I'm testing a Chinese Alpicool DC-powered fridge/freezer which can
> operate directly on 12V or 24V. It has its own set of quirks to deal
> with but so far it doubles the battery run time when it's the only
> load, and may permit a smaller and more efficient modified sine
> inverter for non-motor loads in the daytime.
>
> -jsw

Thanks Jim like I say I've no knowledge on how to build it myself so gathering info in the hope I can get enough to perhaps DIY
Interesting re the Alpicool I've looked at a few DC powered units and thought they were mostly shy of having enough insulation so haven't bought one yet.

[dolmen]

Thanks ads, yes that was the conclusion I'd arrived at. Interesting that you went for a 12V system I was thinking of at least 24V perhaps 48V and being able to use lighter wire in the system, but like I say I don't really have a clue. A similar setup to what you have built would probably meet my needs too.

[Jim Wilkins]

"dolmen" <dob...@gmail.com> wrote in message

news:2b0bcfc1-a41c-467d...@googlegroups.com...

In cool weather the Alpi C20 works well enough as an indoor freezer
set at -18C. Right now my kitchen is at 17C and in midwinter I let the
house drop to 13C. When I put the Alpi in the back of my white SUV on
a sunny 28C day it ran continuously at -12 to -15C until I covered the
cold compartment with a winter parka, leaving the vents clear.

Here in the Northeast USA we suffer summer hurricane and winter ice
storm power outages, sometimes for a week or more. In that case I'd
reset it to -4C which keeps frozen food lightly frosted for a while
but doesn't freeze drinks solid, and greatly increases the battery run
time.

-jsw

[Jim Wilkins]

<ads> wrote in message
news:jqqbhd17kq5j54ma7...@4ax.com...

My system is similarly assembled from whatever I could find
second-hand or build, a little smaller because my property is mostly
shaded. I made V-shaped fold-out legs for my Grape panels from 1/2"
EMT conduit and move them around to dodge shadows when I need several
hundred Watts for discharged batteries, otherwise 1-2A from panels in
fixed locations keeps the backup batteries topped off.

The parts I designed and built because they aren't commecially
available are a 25A fast charger and a float charger for battery
maintenance composed of an LM350 adjustable linear voltage regulator
and this voltage and current meter for feedback:
https://www.amazon.com/DROK-Digital-0-33-00V-0-3-000A-Measurement/dp/B00IZU4D4Q/ref=sr_1_173?s=industrial&srs=9119938011&ie=UTF8&qid=1496089483&sr=1-173
Th voltmeter helps find the lead-acid gassing threshold and then stay
just below it, and the ammeter indicates when the battery is coming
up, fully charged, or degrading from age. The numbers to look for are
in the battery manufacturer's data sheets.

The 25A fast charger is a Variac driving a "50A" (at 20% duty cycle)
arc welder transformer, rectifier and capacitor etc. I designed it
more for experimenting and component testing but it can charge any
battery between 1.5V and 48V and the Variac adapts it to a poorly
regulated generator. If you already have the parts or find them cheap
it's a good use for them, although the welder voltage/current
characteristic is constant current and the voltage can rise too high
if left unattended or unregulated. This DPS5015 switching regulator
works really well and is controllable enough to charge bare Lithiums
or NiCads. I bought it before the 20A model became available.
https://www.amazon.com/uniquegoods-Step-down-Programmable-Adjustable-Regulator/dp/B01N3YSE6S/ref=sr_1_1?s=industrial&ie=UTF8&qid=1528198322&sr=1-1&keywords=dps5015

I learned how to charge sample batteries with lab power supplies when
I became the battery tech at Segway.
http://batteryuniversity.com/learn/article/charging_with_a_power_supply
I add a series diode to keep battery voltage from feeding back into
the power supply if it's switched off.. The DC desulfation technique
they mention does work, sometimes. If you are serious about salvaging
old 12V batteries the Harbor Freight Carbon Pile tester is very
useful.

-jsw

[Jim Wilkins]

"dolmen" <dob...@gmail.com> wrote in message

news:edf09afb-0b2c-4b76...@googlegroups.com...

On Tuesday, June 5, 2018 at 3:04:56 AM UTC+1, ads wrote:

...........

Thanks ads, yes that was the conclusion I'd arrived at. Interesting
that you went for a 12V system I was thinking of at least 24V perhaps
48V and being able to use lighter wire in the system, but like I say I
don't really have a clue. A similar setup to what you have built would
probably meet my needs too.

-----------------

Mine can be configured as 12V or 24V, determined by the loads and the
nonfunctional 24V pure sine UPS I acquired for free. The Alpi can run
on either. I brought the solar panel wiring into the house as
individual 12V pairs and patch them in series or parallel at the
thunderstorm disconnect with nongendered 45A Anderson Powerpole
connectors.

The circuit is conceptually very simple, basically wire it as the
label on the controller shows. However there are subtleties of fusing,
grounding, fault tolerance and battery care etc that I had to research
for myself and I doubt an electrician or electrical engineer would
know unless they had solar experience. I've discovered many times that
electricians don't know much if any theory and engineers rarely
understand the practice. As a tech I had to cover the overlap and know
which one to call and what to ask when I couldn't solve the problem.

For instance one of the input diodes on my 45W Harbor Freight
controller shorted, allowing battery voltage to flow back to the panel
where it could be a serious short circuit hazard. I had added cheap
analog volt and amp meters to the panel leads which showed the voltage
that shouldn't be there at night. A digital meter on the panel
downlead had failed, possibly from static voltage.

Another gotch is stray added resistance in the wiring, likely at loose
or corroded connections. One Ohm is hard to measure but is far too
much at 5A panel current. The Variac+welder power supply can force 10A
through the wiring which makes high resistances easy to find with a
voltmeter.

-jsw

[Johnny B Good]

On Sun, 03 Jun 2018 02:32:40 +0000, Johnny B Good wrote:

====snip====

>

> Modern fridge compressors, I believe, only use 35 to 60 watts when
> running although they may demand 3 to 6 times that for a few seconds
> when starting up. However, I haven't tested this with our own fridge so
> I can't verify this from actual experience.
>
> If you happen to have a really modern fridge/freezer using a linear
> compressor, you won't suffer the 'compressor startup surge' effect which
> simplifies the issue of running it from inverter generator power
> somewhat.

Following up on what I wrote above, I've since run a test with our under
the counter larder fridge using the 2000MU-UK (the 230v version of the
Kill-A-Watt, btw, both manufactured by Prodigit Electronics Co Ltd) and
my Metrawatt analogue wattmeter for measuring the watts and volt amps
consumption, both running, averaged and peak values.

It's actually been several days since I ran the tests (I was hoping to
use another follow response as a chance to include these test results,
hence the delay). The on and off cycle times turned out to be hours
rather than tens of minutes so on the 2nd day of monitoring, I set a
camera up on a small tripod to video the meter readings so I could
capture and replay the startup surge event.

It turns out that my 3 to 6 times running wattage startup surge estimate
was a little on the optimistic side. It peaked at a 1000 watts on the
analogue meter (660W was the 2000MU-UK's best shot at registering this
peak) which turns out to be some 14 times greater than the 65 to 72 watt
steady state consumption of the compressor motor after it has been
running for more than a minute, way higher than I was expecting. :-(

The 2000MU-UK was showing a VA figure of around 135VA and a wattage
reading some 7W higher than the more credible Metrawatt reading. The
averaged over a 34 hour period power consumption, after correcting for
the 7 watt over-read, proved to be 37 watts (324KWH per annum)[1]. The
power factor figure btw, was 0.55 (55%) just about what you might expect
of a domestic fridge compressor motor. The power factor at peak startup
current will be a lot higher since most of the power under such an
extreme surge condition will be resistive losses taking the PF somewhere
around the 80% mark as a best guess.

The only consolation of that assessment is that the 1KW peak isn't going
to translate into a 1.8KVA (at 55% PF) load on the generator when
attempting to power the fridge as the only load, more likely a 1250VA
peak (which may still be enough to cause the generator to immediately
shut down).

Although the UPS's 2KVA 1500W rating will allow it to start the fridge
compressor without tripping out, this relies upon the generator shutting
down to effect the transfer to battery power and the UPS's much beefier
inverter, so a far from ideal 'solution' since you'd have to reset/
restart the generator within a few minutes each time to avoid unnecessary
depletion of the battery. You'd also have to limit the other loads to
500W or less to avoid tripping out the UPS itself.

The most practical way to make use of a 2KVA 1500W rated UPS in this
circumstance would be to insert an automatic load shedding switch[2] with
a reclosure time of ten seconds between the generator and the UPS set to
immediately disconnect the generator before its own protection can
respond with an immediate overload shutdown. You'd still need to limit
the other loads to no more than 500W but at least you'd only lose
generator power for a ten to fifteen second period each time once every 5
hours or so.

I haven't yet tested the chest freezer's load characteristics. The
results from the fridge tests rather put a dent in my enthusiasm for
trying to persuade such a weedy inverter genset to run it even with
careful load management since I suspect its demands will be higher.
However, now that I can see a way around this problem using the higher
surge capacity of the UPS, I'm thinking that perhaps it's worth testing
after all. It might not turn out to be as bad as I thought. In any case,
it's always best to have some actual test results to work from rather
than rely upon assumption alone. At least I'll know exactly where I stand
in regard of my emergency power options.

[1] I hadn't been able to locate the model number rating plate when I
first took a cursory look inside the fridge several days ago assuming it
must have been stuck to the back of the fridge. It was only when I
extricated it from its under the worktop location, just a few hours ago,
that I discovered its absence from the back of the fridge, motivating me
to get on my hands and knees to do a more thorough search of the interior
which finally solved the mystery. I'd had to extract the 'crisper trays'
from the bottom before it was revealed to be stuck to the right hand side
just below the bottom shelf - a hands and knees job indeed, no wonder the
cursory search had come up dry!

This got me a model number (ART 417/G) and the electrical specification
which, as is typical of most electrical specifications, a seeming work of
fiction, apart from the voltage (220-240 V~) and frequency (50Hz - vital
info in the case of induction motor driven appliances), leaving the
fictional information that it had a consumption of 100W and that it was
fused at 13A (this last was no doubt true despite the fact that a 5A fuse
would have entirely adequate).

The 100W is obviously intended to indicate the running wattage after the
initial 1KW startup surge. It certainly would have passed through this
wattage level a second or so after starting up but wouldn't have stayed
within even +/-10% of that figure for more than another second or two
before swiftly settling down to 75W from where it would eventually drop
to 65W over the next two or three hours.

Also included on the label was its energy rating in the form of
0.6KWH/24h, corresponding to an annualised figure of just 219KWH which is
how it's been more normally expressed for domestic fridges and freezers
for at least a decade now. That was a bonus which proved useful since I
couldn't find a free download of the owner's manual in English and the
Dutch language version I perused showed no mention of this energy rating
information.

I can only surmise that my higher estimated 324KWH per annum figure was
due to the summer like temperatures we had been enjoying when I had been
running my tests, along with the fact that the back of the fridge had
been long overdue a spring cleaning which I completed when I'd been
searching for the rating plate information. Considering its age (some 15
years or so, afaicr), it still seems to be doing well and as the door
seals are still in good condition there's no urgent need to replace it
just yet.

[2] I could homebrew such a switch using a current transformer with a
transistor driven relay that can detect precisely when the current
exceeds the 4.3A limit to operate[3] the relay to interrupt the line
current for a ten seconds timeout interval, pre-empting the inverter
genset's built in overload protection. This would allow the more robust
UPS's inverter to deal with such brief overloads automatically without
having to rely on the generator tripping out to effect the transfer to
battery power and all that that entails.

It's a work around solution to a problem most would consider best fixed
with a simple generator upgrade. However, as 'obvious' a solution as that
appears, it does rather overlook the expense, both capital and running
costs, of providing excess capacity just to deal with a 4 or 5 second
event once every 4 or 5 hours of run time.

If it had been merely a choice between spending 280 quid on a 1.5KW
genset and 400 quid on a 2.5KW one, spending the extra 43% choosing the
higher output one (or even 143% if upgrading an existing 1.5KW genset)
would have been the obvious choice. However, since for me, it amounts to
spending an extra 400% to double up on my existing genset rating, such a
work around solution has a very strong cost advantage.

Admittedly, this work around solution does rather depend on my already
having a 1500W/2KVA rated UPS conveniently to hand and one that I know
from experience can handle such extreme surge loadings - the degaussing
surge of a 19 inch colour monitor in point of fact.

[3] I want to disconnect by *operating* a relay rather than the more
common release of a cut out relay typical of the more usual overload
protection circuits. The rationale in this case being that when the
generator is coping with the load. I don't want to be drawing any
additional power holding a relay in its operated state to pass the power
through to the UPS.

It doesn't matter if the the circuit 'fails unsafe' (leaving the genset
output connected) if the genset does trip out anyway since the end result
remains the same - no power to the UPS in either event. When the overload
shedding relay module successfully pre-empts the genset's built in
overload protection, I'll have more genset power to spare than I'd know
what to do with, which makes the few volt amps or watts of power needed
to operate the relay to open its normally closed contacts a non-issue. :-)

--
Johnny B Good

[Jim Wilkins]

"Johnny B Good" <johnny...@invalid.ntlworld.com> wrote in message
news:4%HSC.354038$Xa4.1...@fx29.am4...

>
> Following up on what I wrote above, I've since run a test with our
> under
> the counter larder fridge using the 2000MU-UK (the 230v version of
> the
> Kill-A-Watt, btw, both manufactured by Prodigit Electronics Co Ltd)
> and
> my Metrawatt analogue wattmeter for measuring the watts and volt
> amps
> consumption, both running, averaged and peak values.
>

I ran through the same exercise with my Summit ~45 liter fridge and
APC1400 UPS. An HP digital storage scope and Fluke current probe
showed the starting surge to be 12A for 300mS. The Peak function on a
UT61E meter gave 11.29A. The resistance at the plug is 10.8 Ohms,
which gives about the same result with 120V AC.

The UT61E is a somewhat sketchy implementation of a very good intent.
https://www.markhennessy.co.uk/budget_multimeters/unit_ut61e.htm
The backlight is reportedly present and can be enabled by hacking.
The UT210E is also worth a look.

The Bayite PZEM-061 approximates a KAW for 80-260VAC and up to 100A.

I think a suitable load sensing circuit could be built by connecting
the fridge to the COM contacts of a DPDT relay and sensing the
thermostat closure on the NC side, then turning on the inverter and
energizing the relay with battery DC to power the fridge from the NO
contacts. The relay could stay closed for a fixed delay that's longer
than the fridge run time to avoid the need to sense the shutoff, or
you could use a current transformer and more intelligent (less
reliable?) controller.

My APC1400 UPS doesn't respond to remote serial port turn-on commands
when on battery power, unless I tap into the front panel pushbutton
and beeper and build a controller, so I bought a DC powered Alpicool
fridge/freezer. which gives me considerably more frozen food (ice
cream!!) storage than the Summit, and can travel in the car.
Apparently later APC models actively discourage being (mis)used in
solar battery systems.
-jsw

[Johnny B Good]

On Sat, 09 Jun 2018 08:57:25 -0400, Jim Wilkins wrote:

> "Johnny B Good" <johnny...@invalid.ntlworld.com> wrote in message
> news:4%HSC.354038$Xa4.1...@fx29.am4...
>>
>> Following up on what I wrote above, I've since run a test with our
>> under the counter larder fridge using the 2000MU-UK (the 230v version
>> of the Kill-A-Watt, btw, both manufactured by Prodigit Electronics Co
>> Ltd)
>> and my Metrawatt analogue wattmeter for measuring the watts and volt
>> amps consumption, both running, averaged and peak values.
>>
>>
> I ran through the same exercise with my Summit ~45 liter fridge and
> APC1400 UPS. An HP digital storage scope and Fluke current probe showed
> the starting surge to be 12A for 300mS. The Peak function on a UT61E
> meter gave 11.29A. The resistance at the plug is 10.8 Ohms, which gives
> about the same result with 120V AC.

That strongly suggests that the initial surge is being limited by the
motor's coil resistance which suggests an even higher power factor in
excess of 90%, perhaps even 95% or higher (the windings inductance will
plummet once the iron has been pushed into saturation by such extreme
surge currents).

This is an important factor with inverter gensets which, AFAICS, all
quote wattage ratings at unity power factor with never any mention of a VA
rating, unlike most UPSes. Basically, the limit is effectively the VA
limit and you'll only see the wattage match that VA rating with unity
power factor loads. It's rather handy that my fridge startup load just
about mimics a 1KW resistive load (and your Summit -45 litre fridge, a
1.44KW load for 300ms). :-)

>
> The UT61E is a somewhat sketchy implementation of a very good intent.
> https://www.markhennessy.co.uk/budget_multimeters/unit_ut61e.htm The
> backlight is reportedly present and can be enabled by hacking. The
> UT210E is also worth a look.

I did follow the link and read through the review. Interesting though it
was, I've already got enough DMMs for my immediate needs for the time
being, so that was enough of a side trip thank you very much. :-)

>
> The Bayite PZEM-061 approximates a KAW for 80-260VAC and up to 100A.

That looks to be cheap and handy way to monitor whole house electricity
consumption. The only problems I see is that it effectively duplicates
the electricity meter and, unless there is a clamp on CT option, you'll
have to interrupt the live or neutral wire to fit the CT and tap onto the
live and neutral connections to provide both power and monitoring of the
line voltage.

This isn't quite as bad as it immediately looks since it can be fitted
after the CU isolator switch with the power cut off. Also, it could be
used to monitor a single lighting circuit or ring main or even several
(there seems to be plenty of space in the CT to thread all the relevant
wires in a typical domestic installation through it) which would save it
from merely duplicating the electricity meter's function. You could use
it to monitor the kitchen ring main and/or the electric cooker and/or
oven energy use for instance.

The only thing I'd suggest is that the live feed be taken off a lighting
circuit fuse for safety. I don't fancy taking the risk of a bus bar live
to neutral short via the line voltage connection wires.

There are plenty of more expensive alternatives[1] which can transmit
their readings to a remote data logging unit which data can then be
perused with a PC which, for those interested in such metering projects,
would be a more useful and convenient feature than having to approach the
CU just to check the readings each time, especially if it's located in an
awkward to access spot (under the stairs or at the bottom of a steep
flight of irregular stone steps into the basement).

Still, I suppose the live and neutral feed can be extended easily enough
and ditto for the CT connections so, with a little more effort, it could
be placed somewhere more convenient to keep tabs on its readings. Unless
there's an auto phase reversal correction feature built into it, there's
a 50:50 chance the CT wires will need to be swapped round, an action best
done with the power shut off to avoid the risk of excess voltage in the CT
secondary.

>
> I think a suitable load sensing circuit could be built by connecting the
> fridge to the COM contacts of a DPDT relay and sensing the thermostat
> closure on the NC side, then turning on the inverter and energizing the
> relay with battery DC to power the fridge from the NO contacts. The
> relay could stay closed for a fixed delay that's longer than the fridge
> run time to avoid the need to sense the shutoff, or you could use a
> current transformer and more intelligent (less reliable?) controller.

I'm assuming you're now addressing the issue of handling those once
every 4 or 5 hours, 2 or 3 seconds duration overloading events when the
fridge stat kicks in. That seems a more complicated solution to getting
the UPS to temporarily take over the load from the genset than my own.

>
> My APC1400 UPS doesn't respond to remote serial port turn-on commands
> when on battery power, unless I tap into the front panel pushbutton and
> beeper and build a controller, so I bought a DC powered Alpicool
> fridge/freezer. which gives me considerably more frozen food (ice
> cream!!) storage than the Summit, and can travel in the car. Apparently
> later APC models actively discourage being (mis)used in solar battery
> systems.

I'm guessing the DC powered Alpicool fridge/freezer is designed to run
off a 12v car or leisure battery supply. Since it can freeze stuff, I'm
guessing it must be using a VFD compressor motor with proportional
control of the compressor speed to maintain the required temps, neatly
eliminating the issue of compressor startup surge. You can clarify the
details if I haven't got them spot on.

The statement, "My APC1400 UPS doesn't respond to remote serial port
turn-on commands when on battery power" doesn't on the face of it make
sense since 'being on battery power' is normally shorthand for the UPS
supplying mains voltage using 'battery power' to drive its mains voltage
inverter to serve the protected load.

I can only guess you're referring to an automated shutdown instigated as
a result of a signal from the UPS monitoring S/W in whichever PC was
chosen to issue similar shutdown requests to any other PCs that are also
running off the same UPS protected supply which will complete the shutdown
sequence by issuing a final delayed shutdown request to the UPS so as to
preserve its battery pack from any further unnecessary depletion.

Even if this leaves the UPS in some sort of idle state, waiting for
return of supply so it can recharge its battery pack and ultimately
restore mains power through to the load after short refractory period, it
wouldn't make a lot of sense to allow a restart until at least after
resumption of supply so I can understand the logic in not responding
'when on battery alone with the inverter shut down' to such a startup
request via its remote interface.

Otoh, you might be able to pre-empt the refractory period on return of
supply via the remote interface but only if the battery state is above a
minimum state of charge (typically, from memory, 25% is the minimum
requirement for a UPS restart).

I'm guessing the issue of later APC models actively discouraging being
misused in solar battery systems is to do with using the solar charged
battery as a stand in for its regular battery pack or as a supplementary
battery in parallel to the UPS's own battery pack.

If you're talking about sub 2KVA UPSes such as the SmartUPS700, these
rely upon the very limited run time of their pair of 7AH SLAs to save
their under specced transformers from burning out. The earlier models
just relied on battery voltage monitoring alone to decide when to give up
and shut down since the installed batteries were incapable of burning out
the transformer due to their deliberately limited capacity.

The later models might now be including transformer temperature
monitoring, a feature formerly deemed unnecessary, to force a shutdown
regardless of the battery state; a feature that would spoil the plans of
any solar panel power enthusiast trying to do things on the cheap.

The larger 2KVA and up UPSes with seperate battery box will usually
allow a doubling or tripling up of battery capacity just fine since their
transformers are rated for indefinite run times, even if this does rely
upon forced cooling to ensure this. I should imagine it's these large
UPSes that will be the most amenable to such solar powered setups but if
it were me, I'd be inclined to improve the UPS's ventilation just to be
sure to reduce the thermal stress of extended inverter run times.

[1] There may even be whole house energy monitors with several CT
channels to allow individual circuits to be monitored independently but
I'm only guessing since I've never had enough interest to check out the
availability of such kit. I'm only assuming the existence of such since
that seems such a blindingly obvious feature to have on a more expensive
and comprehensive energy monitoring system.

--
Johnny B Good

[Jim Wilkins]

"Johnny B Good" <johnny...@invalid.ntlworld.com> wrote in message

news:n10TC.853078$7b4.6...@fx12.am4...

It may have a PTC current limiter.
https://www.achrnews.com/articles/108824-ice-breaker-ptc-starting-relays
https://www.amazon.com/uxcell-Refrigerator-Starter-Relay-Black/dp/B00N3WFW5K
The scope showed constant current for the 300mS.

> This is an important factor with inverter gensets which, AFAICS, all
> quote wattage ratings at unity power factor with never any mention
> of a VA
> rating, unlike most UPSes. Basically, the limit is effectively the
> VA
> limit and you'll only see the wattage match that VA rating with
> unity
> power factor loads. It's rather handy that my fridge startup load
> just
> about mimics a 1KW resistive load (and your Summit -45 litre fridge,
> a
> 1.44KW load for 300ms). :-)
>
>>
>> The UT61E is a somewhat sketchy implementation of a very good
>> intent.
>> https://www.markhennessy.co.uk/budget_multimeters/unit_ut61e.htm
>> The
>> backlight is reportedly present and can be enabled by hacking. The
>> UT210E is also worth a look.
>
> I did follow the link and read through the review. Interesting
> though it
> was, I've already got enough DMMs for my immediate needs for the
> time
> being, so that was enough of a side trip thank you very much. :-)

I bought it for datalogging, along with several less expensive
TP4000s.
http://testmeterpro.com/tekpower-tp4000zc/
Except for starting surges DVMs are fast enough to capture most normal
battery and AC power events and the optical isolation suits them to
placement anywhere in the systen without short circuit or common mode
concerns, a problem I had to solve when instrumenting a prototype
electric vehicle. Optically isolated DVMs can accurately measure the
voltages at the battery and at the load and across a shunt in the
negative or positive lead between them with no interference issues.

The TP4000's accuracy with Type K thermocouples is unimpressive but if
you import the data file into a spreadsheet it can apply slush and
teapot calibration corrections. The interface program applies
linearizing corrections to the raw readings that appear on the DVM.

My older, thicker laptops have CardBus and Expresscard slots for
serial or USB port expanders that allow up to four meters per
computer. The separate datalog files can be synchronized by aligning
the time stamps in a spreadsheet. Integrating voltage and current to
total wattage is a simple summation.

>> The Bayite PZEM-061 approximates a KAW for 80-260VAC and up to
>> 100A.
>
> That looks to be cheap and handy way to monitor whole house
> electricity
> consumption. The only problems I see is that it effectively
> duplicates
> the electricity meter and, unless there is a clamp on CT option,
> you'll
> have to interrupt the live or neutral wire to fit the CT and tap
> onto the
> live and neutral connections to provide both power and monitoring of
> the
> line voltage.

I wired it to the outlet strip that distributes emergency power from
my UPS. Normally the strip is plugged into the stove 120V outlet to
serve various cooking appliances and the meter's large backlit display
reminds me to shut them off.

When a night ice storm threatens I plug the APC in to charge through a
KAWez, and the fridge into it through the PZEM-061. Then it becomes
obvious that the APC draws at least twice as much wattage as it
supplies to the fridge, even after the battery float current drops
low. During fridge-only run time tests the VAC-1100A that monitors
battery charge and discharge shows a similar result.

I can shut down the fridge once all its contents fit the Alpi (or a
cooler in the woodshed or the car, weather permitting) and then have
time and battery life to shovel through the snow and ice and fallen
branches to the back of the house and clear enough space for a
generator, again weather permitting. Sometimes we are directly
downwind of Hudson's Bay.

>
> This isn't quite as bad as it immediately looks since it can be
> fitted
> after the CU isolator switch with the power cut off. Also, it could
> be
> used to monitor a single lighting circuit or ring main or even
> several
> (there seems to be plenty of space in the CT to thread all the
> relevant
> wires in a typical domestic installation through it) which would
> save it
> from merely duplicating the electricity meter's function. You could
> use
> it to monitor the kitchen ring main and/or the electric cooker
> and/or
> oven energy use for instance.

US wiring doesn't use ring mains.

> The only thing I'd suggest is that the live feed be taken off a
> lighting
> circuit fuse for safety. I don't fancy taking the risk of a bus bar
> live
> to neutral short via the line voltage connection wires.

The breakers for individual circuits plug directly into and cover the
two hot busbars. The busbar contacts are interleaved such that each
connects to every second breaker in the column, so a double breaker
supplies 240V and a single one supplies 120V from whichever side of
the center-tapped pole transformer happens to be under it. Typically
each 120V circuit is a series string and each 240V circuit drives a
single load, though the rules and practices and level of inspection
have changed over time.

>
> There are plenty of more expensive alternatives[1] which can
> transmit
> their readings to a remote data logging unit which data can then be
> perused with a PC which, for those interested in such metering
> projects,
> would be a more useful and convenient feature than having to
> approach the
> CU just to check the readings each time, especially if it's located
> in an
> awkward to access spot (under the stairs or at the bottom of a steep
> flight of irregular stone steps into the basement).

Since there's relatively little I can do to fine tune appliances
beyond using them less I just plug them into a P4460 KAWez and record
the monthly cost of operation.

That might address the issue of the UPS's wasteful idle current by
allowing the controller to turn it off when not needed, at night when
the fridge is the only load. The APC1400 only complains about the
starting current when the batteries are low.

>> My APC1400 UPS doesn't respond to remote serial port turn-on
>> commands
>> when on battery power, unless I tap into the front panel pushbutton
>> and
>> beeper and build a controller, so I bought a DC powered Alpicool
>> fridge/freezer. which gives me considerably more frozen food (ice
>> cream!!) storage than the Summit, and can travel in the car.
>> Apparently
>> later APC models actively discourage being (mis)used in solar
>> battery
>> systems.
>
> I'm guessing the DC powered Alpicool fridge/freezer is designed to
> run
> off a 12v car or leisure battery supply. Since it can freeze stuff,
> I'm
> guessing it must be using a VFD compressor motor with proportional
> control of the compressor speed to maintain the required temps,
> neatly
> eliminating the issue of compressor startup surge. You can clarify
> the
> details if I haven't got them spot on.

You hit it. It uses a Chinese copy of the Danfoss/Secop compressor,
this one I think:
https://www.secop.com/fileadmin/user_upload/SEPS/datasheets/bd35f_101z0204_r134a_12-24vdc_05-2016_desd100p522.pdf

> The statement, "My APC1400 UPS doesn't respond to remote serial port
> turn-on commands when on battery power" doesn't on the face of it
> make
> sense since 'being on battery power' is normally shorthand for the
> UPS
> supplying mains voltage using 'battery power' to drive its mains
> voltage
> inverter to serve the protected load.
>
> I can only guess you're referring to an automated shutdown
> instigated as
> a result of a signal from the UPS monitoring S/W in whichever PC was
> chosen to issue similar shutdown requests to any other PCs that are
> also
> running off the same UPS protected supply which will complete the
> shutdown
> sequence by issuing a final delayed shutdown request to the UPS so
> as to
> preserve its battery pack from any further unnecessary depletion.

I used the APC command set revealed in apcupsd documentation to write
a status and control program that runs on this laptop.
http://www.apcupsd.org/
The serial cable is nonstandard and battery power appears on one of
the pins. I suspect the port was meant for production line testing.
APC is unhappy that their proprietary protocol was leaked and won't
help.

>
> Even if this leaves the UPS in some sort of idle state, waiting for
> return of supply so it can recharge its battery pack and ultimately
> restore mains power through to the load after short refractory
> period, it
> wouldn't make a lot of sense to allow a restart until at least after
> resumption of supply so I can understand the logic in not responding
> 'when on battery alone with the inverter shut down' to such a
> startup
> request via its remote interface.

Starting the APC1400 on battery power alone requires pushing the Start
button until the beeper sounds, then quickly releasing it, a
technician rather than an operator mode. Unlike other front panel
functions there isn't a serial port command that duplicates it. I can
run it only as needed on batteries during the day but not of course
when I'm asleep.

The APC1400 900W, 1400VA pure sine UPS has a controlled fan and an
Anderson Powerpole connector on the rear panel that serves as a
battery series disconnect, but can easily be reconfigured as an
external input. I leave the method to those able to figure it out for
themselves. The older model I have can be programmed for the number of
VRLA external battery packs, or their wet deep cycle equivalent. I
left the float voltage at the 13.6V AGM level to avoid hydrogen and
equalize the batteries outdoors periodically.

I worked for a former APC engineer for a while and learned a lot about
the problems of hacking a UPS for solar power. He said what you did
about their cost-cutting design.

I've tested it to full load but the fridge draws only around 100W.
However it pulls nearly the full 1400VA to start, and blips the Low
Battery alarm as they get low. .