battery charger.... Repco.

[Lindsay]

Repco are selling these for $159...
8 Stage 30amp
http://catalogues.repco.com.au/catalogue/big-boys-toys/537aa820u.html?pid=promotedCatalogue#pageNo=6&offerId=14362263555598

http://www.australiandirect.com.au/buy/SDPTC12V30AL

The beauty of these chargers is they will attempt to charge a *flat*
battery, and will charge just about anything between 17ah and 300ah, and
any type wet, sla, deepcycle, calcium etc.. most stores only have 1 or 2
in stock.

and as a plus, spend over $100 in their store, wave your RAVC card (or
whichever)and get a 900ah battery jumper pack for $20, and 30% off
storewide.

[D Walford]

Looks good, if I didn't already own 4 battery chargers I might buy one:-)

--
Daryl

[John_H]

Lindsay wrote:

>Repco are selling these for $159...
>8 Stage 30amp
>http://catalogues.repco.com.au/catalogue/big-boys-toys/537aa820u.html?pid=promotedCatalogue#pageNo=6&offerId=14362263555598
>
>http://www.australiandirect.com.au/buy/SDPTC12V30AL
>
>The beauty of these chargers is they will attempt to charge a *flat*
>battery, and will charge just about anything between 17ah and 300ah, and
>any type wet, sla, deepcycle, calcium etc.. most stores only have 1 or 2
>in stock.

So long as it really is 30A RMS.

It's common practice to quote battery chargers at peak voltage... ie
the current they would output at the peak of a sign wave if no
limiting factors applied (or something akin to that).

Similar trick to audio equipment manufacturers quoting PMPO instead of
RMS power.

Consequently the continous output is all too frequently but a fraction
of the stated output.

--
John H

[Noddy]

The specs look pretty good.

I've got a bunch of battery chargers, including a few Ctek models that
are excellent units. The 25 amp one I have is similar to this except it
won't do calcium or gel batteries, and costs about 200 bucks more than
this one.

For this money I'd be keen to give one of these things a try...



--
--
--
Regards,
Noddy.

[Jason James]

On Saturday, July 25, 2015 at 12:37:24 PM UTC+10, John_H wrote:
> Lindsay wrote:
>
> >Repco are selling these for $159...
> >8 Stage 30amp
> >http://catalogues.repco.com.au/catalogue/big-boys-toys/537aa820u.html?pid=promotedCatalogue#pageNo=6&offerId=14362263555598
> >
> >http://www.australiandirect.com.au/buy/SDPTC12V30AL
> >
> >The beauty of these chargers is they will attempt to charge a *flat*
> >battery, and will charge just about anything between 17ah and 300ah, and
> >any type wet, sla, deepcycle, calcium etc.. most stores only have 1 or 2
> >in stock.
>
> So long as it really is 30A RMS.

It supposed to be stated, and in an absence of such its assumed to be RMS. For a sine wave peak is roughly 1.4 times RMS. RMS IIRC = the true heating voltage.

> It's common practice to quote battery chargers at peak voltage... ie
> the current they would output at the peak of a sign wave if no
> limiting factors applied (or something akin to that).
>
> Similar trick to audio equipment manufacturers quoting PMPO instead of
> RMS power.

An old deception for those not familiar with audio power. Where it becomes important, is in design values for heat dissipation. RMS [of a sine wave] is also called the heating voltage equivalent.

In the civil aviation dept I worked for, had its own accepted design safety margins. Only later did we allow MIL-spec stuff as being OK. Unreal :-)

> Consequently the continous output is all too frequently but a fraction
> of the stated output.

Where it gets difficult is when a device can blow even with a very shot o/load. Fast shutdown due over current, power-supplies [eg Crobarring of a fuse] was crucial, as was sacrificial protective zeners across supplies that could go high [voltage wise] and take out very expensive hi-power RF Flat pack transistors.

Jason

[John_H]

Jason James wrote:
>On Saturday, July 25, 2015 at 12:37:24 PM UTC+10, John_H wrote:
>>
>> So long as it really is 30A RMS.
>
>It supposed to be stated, and in an absence of such its assumed to be RMS.
>For a sine wave peak is roughly 1.4 times RMS. RMS IIRC = the true
>heating voltage.

It frequently isn't stated and by some conjuring trick, of which I
don't know the detail, the measured difference is often a factor of 3
(possibly they use 1.414 times 2).

Nor is it difficult to rig the ammeter (where present) to read the
exaggerated value.

Having said that no car battery can take 30A for very long without
boiling but, apart from the deceptive practice, if it won't output at
least 10A continuously into a flat battery the best place for it is on
the merchant's shelf.

--
John H

[John_H]

Noddy wrote:
>
>I've got a bunch of battery chargers, including a few Ctek models that
>are excellent units. The 25 amp one I have is similar to this except it
>won't do calcium or gel batteries, and costs about 200 bucks more than
>this one.

Why won't it charge calciums?

I've got an ancient smart charger which originally appeared in Silicon
Chip magazine well before they were commercially available. It was
subsequently sold as a kit, either by DSE or Jaycar (I've forgotten
which), and charges both conventional lead acid and calciums without
any changes to the sensing circuitry.

Nor, according to the Bosch Automotive Handbook, is there any
practical difference in the charging characterics in spite of what the
charger manufacturers would have you believe. Calciums have been
around since the early eighties and have always worked fine as a
direct replacement for conventionals in any automotive system I've
ever encountered..

--
John H

[Jason James]

On Saturday, July 25, 2015 at 3:56:16 PM UTC+10, John_H wrote:
> Jason James wrote:
> >On Saturday, July 25, 2015 at 12:37:24 PM UTC+10, John_H wrote:
> >>
> >> So long as it really is 30A RMS.
> >
> >It supposed to be stated, and in an absence of such its assumed to be RMS.
> >For a sine wave peak is roughly 1.4 times RMS. RMS IIRC = the true
> >heating voltage.
>
> It frequently isn't stated and by some conjuring trick, of which I
> don't know the detail, the measured difference is often a factor of 3
> (possibly they use 1.414 times 2).

Yep, 1.414 rings a loud bell.

> Nor is it difficult to rig the ammeter (where present) to read the
> exaggerated value.
> Having said that no car battery can take 30A for very long without
> boiling but, apart from the deceptive practice, if it won't output at
> least 10A continuously into a flat battery the best place for it is on
> the merchant's shelf.

Yeah,..30amps is very high. Our 15watt NDBs [non directional beacons used at smallish country airports, had 24v back-up lead-acid batteries. The Tx power-supply would self-disconnect at 22volts. Once 240vac returned, the gear's spike charger would kick in. It was adjusted to *indicate* 7-8amps on a meter. The spike peaks were around 2 times higher in current when viewed on a CRO. The spikes were generated by a full-wave rectifier bridge which had an SCR in place of 2 diodes in the bridge. Their gates were triggered by an oscillator [cant remember what type] whose duty-cycle was set by the battery volts. The spikes were used to punch thru any salting up or sedimentation the electos told me. They maintained the batteries.

Jason

[Noddy]

On 25/07/15 4:12 PM, John_H wrote:

> Why won't it charge calciums?

It does. For some reason I thought it didn't.

[keithr]

On 25/07/2015 4:59 PM, Jason James wrote:
> On Saturday, July 25, 2015 at 3:56:16 PM UTC+10, John_H wrote:
>> Jason James wrote:
>>> On Saturday, July 25, 2015 at 12:37:24 PM UTC+10, John_H wrote:
>>>>
>>>> So long as it really is 30A RMS.
>>>
>>> It supposed to be stated, and in an absence of such its assumed to be RMS.
>>> For a sine wave peak is roughly 1.4 times RMS. RMS IIRC = the true
>>> heating voltage.
>>
>> It frequently isn't stated and by some conjuring trick, of which I
>> don't know the detail, the measured difference is often a factor of 3
>> (possibly they use 1.414 times 2).
>
> Yep, 1.414 rings a loud bell.

Sine wave peak is square root of 2 ie 1.414 times RMS

[Paul Saccani]

On Fri, 24 Jul 2015 23:59:45 -0700 (PDT), Jason James
<h6tg...@outlook.com> wrote:

>On Saturday, July 25, 2015 at 3:56:16 PM UTC+10, John_H wrote:
>> Jason James wrote:
>> It frequently isn't stated and by some conjuring trick, of which I
>> don't know the detail, the measured difference is often a factor of 3
>> (possibly they use 1.414 times 2).
>
>Yep, 1.414 rings a loud bell.

Root 2, for a sine wave, that's the peak of a Root Mean Square value.
And of course, divide the peak by root 2 for the RMS value.

--
Cheers,
Paul Saccani
Perth, Western Australia.

[John_H]

Noddy wrote:
>On 25/07/15 4:12 PM, John_H wrote:
>
>> Why won't it charge calciums?
>
>It does. For some reason I thought it didn't.

I'd have been very surprised if that weren't the case... since it's
highly unlikely to have any means of recognising a calcium battery, at
least in the discharged state.

The smart charger manufacturers like to claim calciums need a higher
voltage to attain full charge when for all practical purposes the
difference in total charge is SFA. Supposedly a calcium needs 14.7V
whereas a conventional lead acid only requires 14.4V yet plenty of
older automotive systems only ever outputed 13.8V (DC generators).
Even those systems work fine with calciums and if anything the
batteries last longer.

The bottom line being that there's no point in paying extra for a
charger claimed to be designed for calciums.

--
John H

[Lindsay]

hehe I've got a few as well, inc the Ctek clones Aldi sold which wont
charge a very flat battery, a couple of small Arlec 4 amp jobbies, and a
projecta 7 stage 16 amp one.

I bought this one because the projecta seems to takes ages to charge a
210ah deep cycle battery, this one should do it in half the time.

[Lindsay]

just so it charges my deep cycle batteries faster than the current
charger, then I'll be happy...

[Lindsay]

I like the ability to simply look at it, and it tells ya how far
advanced it is in charging, what state it's in, and it's all easy to see
and understand, unlike my Projecta, which has a scale drawn on the
underneath, and you have to check which light is flashing/fixed against
the scale.
Gave my ride-on mower battery a tickle-up, and 15 mins later... done.
I'm happy with it...
>
>
>

[John_H]

Jason James wrote:
>
>Yeah,..30amps is very high. Our 15watt NDBs [non directional beacons used
>at smallish country airports, had 24v back-up lead-acid batteries.
>The Tx power-supply would self-disconnect at 22volts. Once 240vac
>returned, the gear's spike charger would kick in. It was adjusted to
>*indicate* 7-8amps on a meter. The spike peaks were around 2 times
>higher in current when viewed on a CRO. The spikes were generated by a
>full-wave rectifier bridge which had an SCR in place of 2 diodes in
>the bridge. Their gates were triggered by an oscillator [cant remember
>what type] whose duty-cycle was set by the battery volts. The spikes
>were used to punch thru any salting up or sedimentation the electos
>told me. They maintained the batteries.

Sounds very similar to my 20 y.o. DIY smart charger which has a pulsed
(square wave) output and, from memory, it also works by varying the
mark/space ratio using a thryristor (SCR) in conjunction with a full
wave rectifier. It uses the space to determine the state of charge.
Open circuit output is 55V on the peaks, measured on a CRO, so it
probably isn't very smart to use it in car with the battery connected.
It automatically selects between 6, 12 and 24V and charges in three
stages, starting at 10A (RMS). Maximum output is determined by the
transformer's VA rating, which is what makes high output chargers
expensive (and largely unnecessary).

The designer called it an automatic charger as the term smart charger
wasn't around at that time. The nearest commercial equivalents used
simple voltage regulators to maintain constant output and only handled
the one voltage.

--
John H

[D Walford]

On 26/07/2015 9:31 AM, Lindsay wrote:
> On 25/07/2015 12:13 PM, D Walford wrote:
>> On 25/07/2015 11:43 AM, Lindsay wrote:
>>> Repco are selling these for $159...
>>> 8 Stage 30amp
>>> http://catalogues.repco.com.au/catalogue/big-boys-toys/537aa820u.html?pid=promotedCatalogue#pageNo=6&offerId=14362263555598
>>>
>>>
>>>
>>>
>>> http://www.australiandirect.com.au/buy/SDPTC12V30AL
>>>
>>> The beauty of these chargers is they will attempt to charge a *flat*
>>> battery, and will charge just about anything between 17ah and 300ah, and
>>> any type wet, sla, deepcycle, calcium etc.. most stores only have 1 or 2
>>> in stock.
>>>
>>> and as a plus, spend over $100 in their store, wave your RAVC card (or
>>> whichever)and get a 900ah battery jumper pack for $20, and 30% off
>>> storewide.
>>>
>> Looks good, if I didn't already own 4 battery chargers I might buy one:-)
>
> hehe I've got a few as well, inc the Ctek clones Aldi sold which wont
> charge a very flat battery

I have one of those and have the same problem.

, a couple of small Arlec 4 amp jobbies, and a
> projecta 7 stage 16 amp one.
>

I have a projecta charger that's always connected to my boat batteries,
before I bought it the batteries would go flat and I was replacing at
least one a year but since I've kept them fully charged I haven't
replace one.

> I bought this one because the projecta seems to takes ages to charge a
> 210ah deep cycle battery, this one should do it in half the time.
>

That's what you want:-)


--
Daryl

[Trevor Wilson]

On 25/07/2015 12:37 PM, John_H wrote:

**It is clearly a switch mode device. As such, it should meet it's
published with ease. Linear supplies are a different matter.

--
Trevor Wilson
www.rageaudio.com.au

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

[Noddy]

On 26/07/15 8:45 AM, John_H wrote:

> I'd have been very surprised if that weren't the case... since it's
> highly unlikely to have any means of recognising a calcium battery, at
> least in the discharged state.
>
> The smart charger manufacturers like to claim calciums need a higher
> voltage to attain full charge when for all practical purposes the
> difference in total charge is SFA. Supposedly a calcium needs 14.7V
> whereas a conventional lead acid only requires 14.4V yet plenty of
> older automotive systems only ever outputed 13.8V (DC generators).
> Even those systems work fine with calciums and if anything the
> batteries last longer.
>
> The bottom line being that there's no point in paying extra for a
> charger claimed to be designed for calciums.

I actually RTFM last night for the first time since I got the thing, and
it doesn't mention calcium batteries at all other than to say that it's
suitable for them.

[Noddy]

On 26/07/15 9:36 AM, Lindsay wrote:

> I like the ability to simply look at it, and it tells ya how far
> advanced it is in charging, what state it's in, and it's all easy to see
> and understand, unlike my Projecta, which has a scale drawn on the
> underneath, and you have to check which light is flashing/fixed against
> the scale.
> Gave my ride-on mower battery a tickle-up, and 15 mins later... done.
> I'm happy with it...

Excellent.

I have 4 "Projecta" battery chargers, and after calling the company to
complain about a brand new one dying after 3 weeks and being told "You
get what you pay for" I told them they could shove their charges up
their arse and I'd never buy another one.

Of the 4 the one the died went in the bin and was replaced with a Ctek
trickle charger, and the others will be replaced with better units as
they shit themselves.

I may go out to Repco and get one of these things today seeings how it's
such a shit day and I can't be bothered doing anything else.

[John_H]

Lindsay wrote:
>
>just so it charges my deep cycle batteries faster than the current
>charger, then I'll be happy...

How long do you expect it to take (without damaging the batteries)?

The main purpose of high output chargers is to rapidly impart a
useable charge in a dead flat battery (eg to start a car). To fully
charge it requires a lower rate corresponding to to the state of
charge and the capacity of the battery (AmpHr)... which is why smart
chargers have stepped charging rates.

For a typical battery 10A (RMS) is around the practical limit for most
of the charging cycle which will take around 10 hours to fully charge
a relatively large car battery from dead flat. You probably won't
save a lot of time by having a significantly higher initial charge
rate which can't be maintained without destroying the battery.

--
John H

[Clocky]

I think the only practical problem perhaps is when charging from flat in
that Calcium chargers are staged whereas conventional chargers may
detect that a Calcium battery is fully charged when it only has a
surface charge and cut out.

FWIW I've had little luck with switch mode supply type chargers and
rolled my own using a transformer for the odd time I need to charge a
battery. It's fairly low current so it's slow, but it does the job and
so far no problems charging either Calciums or Lead-acids.

[John_H]

Clocky wrote:
>
>FWIW I've had little luck with switch mode supply type chargers and
>rolled my own using a transformer for the odd time I need to charge a
>battery. It's fairly low current so it's slow, but it does the job and
>so far no problems charging either Calciums or Lead-acids.

Do you happen to own a laboratory type power supply?

0-30V 5A supplies with adjustable current limiting are common, if not
essential for electronics work. They work fine as battery chargers
and especially for small SLA's which require a considerably lower
charging current than car batteries.

--
John H

[Xeno]

I have a 35+ year old 4 amp Arlec and it still suits my needs. When the
battery is fully charged, it drops to trickle charge, about an amp, and
that's all I've ever needed. No need to fast charge batteries, just
shortens their life.

--

Xeno

[Lindsay]

On 26/07/2015 10:35 AM, Noddy wrote:
> On 26/07/15 9:36 AM, Lindsay wrote:
>
>> I like the ability to simply look at it, and it tells ya how far
>> advanced it is in charging, what state it's in, and it's all easy to see
>> and understand, unlike my Projecta, which has a scale drawn on the
>> underneath, and you have to check which light is flashing/fixed against
>> the scale.
>> Gave my ride-on mower battery a tickle-up, and 15 mins later... done.
>> I'm happy with it...
>
> Excellent.
>
> I have 4 "Projecta" battery chargers, and after calling the company to
> complain about a brand new one dying after 3 weeks and being told "You
> get what you pay for" I told them they could shove their charges up
> their arse and I'd never buy another one.

Ok, we can add Projecta to Telstra, Aus post and transurban :-D

>
> Of the 4 the one the died went in the bin and was replaced with a Ctek
> trickle charger, and the others will be replaced with better units as
> they shit themselves.
>
> I may go out to Repco and get one of these things today seeings how it's
> such a shit day and I can't be bothered doing anything else.

I've got the blow heater going in here whilst i'm fitting up the new
compressor.. it's fucking freezing outside. I'm about 500m from the
waters edge of Port Phillip, and it's blowing it's tits out. And i'm
missing two fittings. If i cant salvage 'em or make 'em up out of other
bits, i'm going home for a fucking big whiskey :-D
>
>
>

[Lindsay]

On 26/07/2015 10:45 AM, John_H wrote:
> Lindsay wrote:
>>
>> just so it charges my deep cycle batteries faster than the current
>> charger, then I'll be happy...
>
> How long do you expect it to take (without damaging the batteries)?

Well, from memory, the projecta 16a would take nearly 10 hours to charge
a 210amp deep cycle battery, so i can only presume the new charger would
take 1/2 the time and without damaging the battery. If it's gunna damage
the battery, it's not worth having.

>
> The main purpose of high output chargers is to rapidly impart a
> useable charge in a dead flat battery (eg to start a car). To fully
> charge it requires a lower rate corresponding to to the state of
> charge and the capacity of the battery (AmpHr)... which is why smart
> chargers have stepped charging rates.
>
> For a typical battery 10A (RMS) is around the practical limit for most
> of the charging cycle which will take around 10 hours to fully charge
> a relatively large car battery from dead flat. You probably won't
> save a lot of time by having a significantly higher initial charge
> rate which can't be maintained without destroying the battery.

I dont understand. How can it destroy the battery when it's supposed to
charge it properly? The batteries I'm charging arent car batteries

http://batteryguru.com.au/Vision-VRLA-6FM120SD-12V-120Ah-Industrial-Battery-AGM-Deep-Cycle-Battery?keyword=vision%206fm
and the absolutley LAST thing I wanna do is stuff 'em...


>

[Jason James]

Indeed, they're very handy,..used to limit the current to non-destructive levels during fault-finding and some ccts which if off tune or had decoupling probs could take-off and draw megacurrent [eg parasitic osc in audio power-amps]. Nice constant current sources too.

Ours were 0-55v and 0-5 amps.Brilliant devices.

Jason

[Paul Saccani]

On Sun, 26 Jul 2015 13:15:20 +1000, Lindsay
<ask.me...@nunnya.business.com.au> wrote:

>> For a typical battery 10A (RMS) is around the practical limit for most
>> of the charging cycle which will take around 10 hours to fully charge
>> a relatively large car battery from dead flat. You probably won't
>> save a lot of time by having a significantly higher initial charge
>> rate which can't be maintained without destroying the battery.
>
>I dont understand. How can it destroy the battery when it's supposed to

>charge it properly? The batteries I'm charging arent car batteries.

John is saying that a high charge rate can't be sustained without
damaging the battery. That's mainly due to overheating. And that as
a consequence, a smart charger that doesn't damage the battery won't
be much faster in practice if its maximum charge rate exceeds 10 A,
because it will reduce its charge rate.

Personally, I'm pretty much over smart chargers... ;)

[Paul Saccani]

On Sun, 26 Jul 2015 10:35:22 +1000, Noddy <m...@wardengineering.com>
wrote:

>On 26/07/15 9:36 AM, Lindsay wrote:
>
>> I like the ability to simply look at it, and it tells ya how far
>> advanced it is in charging, what state it's in, and it's all easy to see
>> and understand, unlike my Projecta, which has a scale drawn on the
>> underneath, and you have to check which light is flashing/fixed against
>> the scale.
>> Gave my ride-on mower battery a tickle-up, and 15 mins later... done.
>> I'm happy with it...
>
>Excellent.
>
>I have 4 "Projecta" battery chargers, and after calling the company to
>complain about a brand new one dying after 3 weeks and being told "You
>get what you pay for" I told them they could shove their charges up
>their arse and I'd never buy another one.

A wise move. Thankfully, I've never spent my own coin on one, but
I've had six die on me. Mainly, it's the thermal fuse in the
transformer that goes on them, and most of the projecta transformers
have welded cores, so it isn't practical to change it. But if you
still have them, keeping them cool by reducing the duty cycle is
probably the best way to stop from dying.

[John_H]

Lindsay wrote:
>On 26/07/2015 10:45 AM, John_H wrote:
>> Lindsay wrote:
>>>
>>> just so it charges my deep cycle batteries faster than the current
>>> charger, then I'll be happy...
>>
>> How long do you expect it to take (without damaging the batteries)?
>
>Well, from memory, the projecta 16a would take nearly 10 hours to charge
>a 210amp deep cycle battery, so i can only presume the new charger would
>take 1/2 the time and without damaging the battery. If it's gunna damage
>the battery, it's not worth having.

Sounds like your present charger is already operating at close to the
optimum charge rate, as will a larger smart charger as it will still
adjust its charge rate to a similar value after a short period at a
higher rate.

Consequently a larger charger won't charge the same battery in half
the time if it's working as it should. You would stand to damage the
battery if it did, so hopefully it won't. :)

--
John H

[Noddy]

On 26/07/15 1:01 PM, Lindsay wrote:

> Ok, we can add Projecta to Telstra, Aus post and transurban :-D

Yes, we can :)

> I've got the blow heater going in here whilst i'm fitting up the new
> compressor.. it's fucking freezing outside. I'm about 500m from the
> waters edge of Port Phillip, and it's blowing it's tits out. And i'm
> missing two fittings. If i cant salvage 'em or make 'em up out of other
> bits, i'm going home for a fucking big whiskey :-D

Lol :)

Good idea :)

[Jason James]

Agree,..I have an old 1st generation electric blanket stepped transformer which was capable of 13vac,15vac and 17vac at around 4amps max. Fitted a DSE 30amp diode bridge mounted on some L section aluminium with a high speed computer fan blowing air down a duct in which the bridge and tranny vented plastic box was for cooling. It always works, and doesnt stink of burning enamel insulation as long as the high setting [6 amps into flat battery] isnt used for more than 10 mins. The 2 lessor settings are OK at 3amps and 1.5amps.

Those DSE 30amp diode bridges are as bullet-proof as the old selenium rectifier bridges used on early chargers. :-)

Jason

[jonz]

"Noddy" <m...@wardengineering.com> wrote in message
news:mp1se7$4uv$1...@dont-email.me...

~~~~~~~~~~~~~~~~~~~~~~~~
Yeah, fuck real life. get on the piss..........Fucken copout...... How
about a comeback on my post of a few days ago regarding yer bullshit on
tandem drive?......Gone very silent there boy?....You are a full of shit and
*WRONG*...... (Only if U can find time considering Pissing and Moaning about
Telstra, et al, seems to occupy most of yer waking moments.....A whinging
know nothing wanker, sums U up) Caio for now.

[D Walford]

I bought one of those last week on ebay for $69.50 to use as a power
supply for a slot car set for the grand kids, it works very well, I can
turn it down so the 3yr old can control it them crank it up if the big
kids want to play.
http://www.ebay.com.au/itm/New-Digital-30V-5A-Variable-DC-Power-Supply-Adjustable-Lab-Grade-AU-Stock-/111552962817?pt=LH_DefaultDomain_15&hash=item19f9132101

--
Daryl

[D Walford]

Don't blame you, its bloody cold.


--
Daryl

[D Walford]

Have a look on the battery, it might say what the max charge amps are,
if not call the supplier and ask for a recommendation.

--
Daryl

[Noddy]

On 26/07/15 6:23 PM, jonz wrote:

> ~~~~~~~~~~~~~~~~~~~~~~~~
> Yeah, fuck real life. get on the piss..........Fucken copout...... How
> about a comeback on my post of a few days ago

How about you go fuck yourself you inbred lump of oily shit.

[jonz]

"Noddy" <m...@wardengineering.com> wrote in message

news:mp2ctq$he3$1...@dont-email.me...

> On 26/07/15 6:23 PM, jonz wrote:
>
>> ~~~~~~~~~~~~~~~~~~~~~~~~
>> Yeah, fuck real life. get on the piss..........Fucken copout...... How
>> about a comeback on my post of a few days ago
>
> How about you go fuck yourself you inbred lump of oily shit.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~
What a response....says it all about you....(All very little of it)....No
argument, no reason, and no balls.....as U are wont to advise others,,,Go
top yerself U waste of space...( a lying one at that). Wonder why yer Hori
Missus puts up with U....

[Noddy]

On 26/07/15 8:56 PM, jonz wrote:

> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> What a response....says it all about you....(All very little of it)....No
> argument, no reason, and no balls.....as U are wont to advise others,,,Go
> top yerself U waste of space...( a lying one at that). Wonder why yer Hori
> Missus puts up with U....

And there's some more of that commercial grade irony we get around here
Folks. Pissing and moaning from a useless tub o' lard who has done
*nothing* since he's been here other than spend his time pissing and
moaning....

[Xeno]

Just how is that different from you spending all your time pissing and
moaning?


--

Xeno

[Clocky]

On 26/07/2015 10:17 AM, John_H wrote:
> Clocky wrote:
>>
>> FWIW I've had little luck with switch mode supply type chargers and
>> rolled my own using a transformer for the odd time I need to charge a
>> battery. It's fairly low current so it's slow, but it does the job and
>> so far no problems charging either Calciums or Lead-acids.
>
> Do you happen to own a laboratory type power supply?
>

Yep.

> 0-30V 5A supplies with adjustable current limiting are common, if not
> essential for electronics work. They work fine as battery chargers
> and especially for small SLA's which require a considerably lower
> charging current than car batteries.
>

They sure do, but I charge my batteries in the garage hence I have
separate chargers for car batteries and smaller SLA's. I don't need to
charge batteries often, so that works ok for me.

[Clocky]

Do yourself a favour and take the cover off and make sure the earth lead
to the chassis (nut and bolt on the transformer) is secure.

[Clocky]

Adding a computer case fan if none is present is a good way to increase
life expectancy too.

[D Walford]

OK will do, I assume its a known fault?

--
Daryl

[Clocky]

It's not so much a fault as something to watch out for with any of these
Chinese power supplies at that price point as quality control can be a
little indifferent.

I have seen a video where the nut was loose from factory requiring a
spring washer to secure it on a model that looked identical to the one
you have (might have been a different rebranding but most likely from
the same factory).

Yours will probably be fine but worth checking just to be sure as it's a
simple fix.

[John_H]

D Walford wrote:
>
>Have a look on the battery, it might say what the max charge amps are,
>if not call the supplier and ask for a recommendation.

There will be a formula somewhere based on the battery's capacity in
AmpHr but that won't help where smart chargers are concerned because
the charge rates are preset to match the smallest battery it's
intended to charge. While it's possible to design a charger that
maximises the charge rate to suit an individual battery such a design
almost certainly wouldn't be commercially viable.

The other major consideration is to prevent overcharging which is what
smart chargers do by switching to a float mode (lower voltage) when
the battery is fully charged. Overcharging is both harmful and
dangerous.

Another alternative would be a regulated charger, which was the best
option before smart chargers came along but you still have to remember
to switch them off, especially the larger ones. Consequently most of
the commercial offerings don't have very high charging rates either
although they're easy enough to make.

There also used to be rapid chargers (maybe they still exist) but they
were only intended to impart a useable charge to a dead flat battery
(which is what the larger smart chargers should also do). The rate
they work at will see the average car battery boiling within a very
short time and can't be maintained for longer than a few minutes. At
a guess, the smart chargers probably control it with a timer.

It's also a dead cert that the transformer in the typical smart
charger won't be able to maintain a fast charge rate for very long,
with transformers being the most expensive part of any charger... and
by extension, the heaviest charger is likely to be the best. :)

--
John H

[D Walford]

On 27/07/2015 9:15 AM, John_H wrote:
> D Walford wrote:
>>
>> Have a look on the battery, it might say what the max charge amps are,
>> if not call the supplier and ask for a recommendation.
>
> There will be a formula somewhere based on the battery's capacity in
> AmpHr but that won't help where smart chargers are concerned because
> the charge rates are preset to match the smallest battery it's
> intended to charge. While it's possible to design a charger that
> maximises the charge rate to suit an individual battery such a design
> almost certainly wouldn't be commercially viable.
>
> The other major consideration is to prevent overcharging which is what
> smart chargers do by switching to a float mode (lower voltage) when
> the battery is fully charged. Overcharging is both harmful and
> dangerous.

Where I did my apprenticeship we had a battery charger that could charge
at a very high rate plus charge a dozen or more batteries at the same time.
Because it was a bit dangerous the boss used to look after it but even
he'd forget to watch it sometimes and I remember quite a few batteries
destroyed by overcharging.


--
Daryl

[Jason James]

I bought an AutoXS charger on sale from Aldi for $27. It senses whether 6 or 12v battery, or you can manually select one of 3 settings>> 6v @ 0.8A with a motorcycle icon, 12v @0.8A or 3.8A if flat or low with a car icon, and a universal range with no icon. Not sure of this ranges current,..but all 3 have auto-shutoff with a charge indicator>> showing On charge or Off.

There is also a battery volts indicator to advise of charging progress.

Bloody thing works really good, and for SFA money :-)

Jason

[John_H]

D Walford wrote:
>
>Where I did my apprenticeship we had a battery charger that could charge
>at a very high rate plus charge a dozen or more batteries at the same time.
>Because it was a bit dangerous the boss used to look after it but even
>he'd forget to watch it sometimes and I remember quite a few batteries
>destroyed by overcharging.

I've still got one of those chargers, which a lot of garages used to
have! It weighs a tonne (well almost) and hasn't been used for yonks.

The maximum rate for that type of charger is still determined by the
smallest capacity battery it was likely to be used for with 10A being
typical. Half wave vacuum rectifiers limited the current but because
the output voltage wasn't regulated you had to be extremely careful to
avoid overcharging, the standard method being to monitor the battery
electrolyte specific gravity (SG) with a hydrometer.

Modern sealed batteries rendered them totally obsolete.

--
John H

[Noddy]

On 27/07/15 10:17 AM, Jason James wrote:

>
> I bought an AutoXS charger on sale from Aldi for $27. It senses
> whether 6 or 12v battery, or you can manually select one of 3
> settings>> 6v @ 0.8A with a motorcycle icon, 12v @0.8A or 3.8A if
> flat or low with a car icon, and a universal range with no icon. Not
> sure of this ranges current,..but all 3 have auto-shutoff with a
> charge indicator>> showing On charge or Off.
>
> There is also a battery volts indicator to advise of charging
> progress.
>
> Bloody thing works really good, and for SFA money :-)

It does indeed :)

I bought one of those about 6 months ago to run as a trickle charger to
keep my "jump start" battery primed, and it does work pretty well as you
say. My only criticism of it is that if you have a power outage (which
we do here on an almost weekly basis) it forgets where you have it set
and reverts to being a digital voltmeter which makes them unreliable in
"set and forget" scenarios.

[F Murtz]

Except that it wont charge if initial battery voltage is too low,I
sometimes have to put a normal charger on for a minute, so it can see
the voltage it wants if I have left the battery get too low (stupidly)

[D Walford]

They do but they won't charge a completely flat battery, excellent for
maintaining a battery that you don't use much such a boat or a spare car
you don't drive often.


--
Daryl

[John_H]

You've also got yourself a regulated battery charger and probably for
less money than you'd expect to pay for a dedicated charger with
anything like the same capabilities. :)

Just make sure not to have the current limiting set higher than the
specified continuous output, which might be less than 5A. For SLA's
the maximum initial charging current is usually marked on the case but
a safer option is to use Ah/10. Same rule of thumb also applies to
car batteries.

--
John H

[Jason James]

yeah, we went thru a period where if it only spitted rain, we'd lose power. The alligator clips on the charger would set you back $10 on their own :-)

jason

[D Walford]

On 27/07/2015 3:29 PM, John_H wrote:
> D Walford wrote:
>> On 26/07/2015 12:17 PM, John_H wrote:
>>>
>>> 0-30V 5A supplies with adjustable current limiting are common, if not
>>> essential for electronics work. They work fine as battery chargers
>>> and especially for small SLA's which require a considerably lower
>>> charging current than car batteries.
>>>
>> I bought one of those last week on ebay for $69.50 to use as a power
>> supply for a slot car set for the grand kids, it works very well, I can
>> turn it down so the 3yr old can control it them crank it up if the big
>> kids want to play.
>> http://www.ebay.com.au/itm/New-Digital-30V-5A-Variable-DC-Power-Supply-Adjustable-Lab-Grade-AU-Stock-/111552962817?pt=LH_DefaultDomain_15&hash=item19f9132101
>
> You've also got yourself a regulated battery charger and probably for
> less money than you'd expect to pay for a dedicated charger with
> anything like the same capabilities. :)
>

Certainly looks that way, it was also a lot cheaper than what I paid for
the 12v power supply for my RC car and heli battery charger, I think I
paid more than double.

> Just make sure not to have the current limiting set higher than the
> specified continuous output, which might be less than 5A. For SLA's
> the maximum initial charging current is usually marked on the case but
> a safer option is to use Ah/10. Same rule of thumb also applies to
> car batteries.
>

Unlikely that I will use it to charge car batteries but I will keep that
in mind if I do.

--
Daryl

[Jason James]

Remember the old charge/discharge current meters in old cars [now at least]? Once you start the car, the alternator goes full output which is circa 40amps in the early 70s'alternators allowing for ignition current subtraction. Or IOWs there is no provision for AH/10. Just a thought.

Jason

[Clocky]

Yeah the SCA charger I had was the same. It's biggest issue was that it
only lasted 6 months thanks to really cheap and crappy componentry in
it's switchmode design so I gutted it and it's case now houses my own
homebrew charger.

[Jason James]

I fail to see the reasoning behind their insistence to have the battery having some charge before charging. What do they think happens to a battery when left on feeding a lamp ? Stupidoo :-)

Jason

[D Walford]

On 28/07/2015 10:45 AM, Jason James wrote:

>>>>
>>> Except that it wont charge if initial battery voltage is too low,I
>>> sometimes have to put a normal charger on for a minute, so it can see
>>> the voltage it wants if I have left the battery get too low (stupidly)
>>
>>
>> Yeah the SCA charger I had was the same. It's biggest issue was that it
>> only lasted 6 months thanks to really cheap and crappy componentry in
>> it's switchmode design so I gutted it and it's case now houses my own
>> homebrew charger.
>
> I fail to see the reasoning behind their insistence to have the battery having some charge before charging. What do they think happens to a battery when left on feeding a lamp ? Stupidoo :-)
>

Totally flattening most lead acid batteries will kill them very quickly
so maybe they think that if a battery has little or no voltage its
beyond charging?
That sort of charger isn't going to much good for deep cycle batteries.



--
Daryl

[Jason James]

Maybe,..its not my field, but I have some comments>

> That sort of charger isn't going to much good for deep cycle batteries.

Switch-mode power supplies have feedback so the battery condition [as it charges] tells the square-wave generator to apply more ON time from the SM if the battery is still low, or less ON time as it approaches fully-charged. The popular analogy is a varying mark-space ratio roughly similar to Morse code.

If the battery is flat, as in most cases if lights are left on in a car, the battery if in good order otherwise, will take as much current as it can get. All the designers need to do, is to limit the max current to a level consistent with the power handling limits of the transformer and semiconductors in the power/output end of the cct. Some headroom is designed in for safety/reliability.

Jason

[D Walford]

On 28/07/2015 12:12 PM, Jason James wrote:
> On Tuesday, July 28, 2015 at 11:41:11 AM UTC+10, D Walford wrote:
>> On 28/07/2015 10:45 AM, Jason James wrote:
>
>
>>> I fail to see the reasoning behind their insistence to have the battery having some charge before charging. What do they think happens to a battery when left on feeding a lamp ? Stupidoo :-)
>>>
>> Totally flattening most lead acid batteries will kill them very quickly
>> so maybe they think that if a battery has little or no voltage its
>> beyond charging?
>
> Maybe,..its not my field, but I have some comments>

I'm trying to charge a battery that is showing only 10.9volts, Aldi
charger isn't interested so I've connected my old charger and it seems
to be charging OK, I'm guessing that the Aldi charger needs min 11volts
before it will charge, must be some reason why its like that but I don't
really know why.

>
>
>> That sort of charger isn't going to much good for deep cycle batteries.
>
> Switch-mode power supplies have feedback so the battery condition [as it charges] tells the square-wave generator to apply more ON time from the SM if the battery is still low, or less ON time as it approaches fully-charged. The popular analogy is a varying mark-space ratio roughly similar to Morse code.
>
> If the battery is flat, as in most cases if lights are left on in a car, the battery if in good order otherwise, will take as much current as it can get. All the designers need to do, is to limit the max current to a level consistent with the power handling limits of the transformer and semiconductors in the power/output end of the cct. Some headroom is designed in for safety/reliability.
>

You seem to know a lot more about that sort of thing than I do:-)


--
Daryl

[Jason James]

On Tuesday, July 28, 2015 at 12:53:08 PM UTC+10, D Walford

> I'm trying to charge a battery that is showing only 10.9volts, Aldi
> charger isn't interested so I've connected my old charger and it seems
> to be charging OK, I'm guessing that the Aldi charger needs min 11volts
> before it will charge, must be some reason why its like that but I don't
> really know why.

In the old days, you could access the joining lead straps between each cell on top of the battery. If your battery is showing 10.9volts, it seems to me that there maybe a shorted cell, and if there was access you could suss this out easily. If one cell is shorted, it should show up on a hydrometer as diametrically different to the other cells. Another way is to see if one cells isnt fizzing like the others during charging with reasonably hi current.

I'd be careful not to put it in a vehicle unless its showing over 12.7 or close to, volts. Otherwise the alternator will be going flatchat continually.

Jason

[Paul Saccani]

It's seen as not being connected. The simple solution is to add a
momentary spst switch to the positive rail before the smarts. Then,
when you put a flat battery on, you push the button. Usually, that's
enough to defeat the logic with one simple push. If not, you might
need to hold it down some, or put a standard switch in, just for
starting dead batteries.

A lot of the earlier ones came out like that, but it reduces costs if
you leave it out.... ;)
--
Cheers,
Paul Saccani
Perth, Western Australia.

[news13]

On Mon, 27 Jul 2015 09:15:00 +1000, John_H wrote:


> It's also a dead cert that the transformer in the typical smart charger
> won't be able to maintain a fast charge rate for very long, with
> transformers being the most expensive part of any charger... and by
> extension, the heaviest charger is likely to be the best. :)

AFAIK, many of the modern chargers do not use transformers, but inverters.
stuff like PowerTeck(Jaycar) and C-teck. IME, it is only the older cheap
stuff that came with a transformer, and little else. Caveat, I haven't
purchased a new one for over ten years.

[Jason James]

You can pick the SM piggy back supplies by their lightness. Not all that stoked with the idea of mains being a blown component or two away from the output !

Jason

[John_H]

Jason James wrote:
>
>Remember the old charge/discharge current meters in old cars [now
>at least]? Once you start the car, the alternator goes full output
>which is circa 40amps in the early 70s'alternators allowing for
>ignition current subtraction. Or IOWs there is no provision for AH/10.
>Just a thought.

Because a car battery is normally in a near fully charged state its
voltage will be sufficiently close to the alternator's regulated
voltage that the output current won't reach peak, even after starting.
If perchance it did it would only need to be for a very short period
to top up the charge. After an initial kick the ammeter should drop
back to a low reading within a minute or so.

Different story if you run the battery flat (eg leave the lights on)
and then jump start the engine. Do it regularly and the battery won't
survive for long. Ideally a dead flat battery should always be
charged out of the car.

--
John H