[Elecraft] 120V vs 240V
W8JH
I will need to add a circuit for a KPA-500. It is less than 25 feet from the
panel. Other than the cost of wire for the circuit is there any
advantage/disadvantage to feeding this amp 120V or 240V? It would have it's
own circuit so the voltage droop on 120V would be minimal I guess.
73,
Joe W8JH
K3 1713
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Barry
For a 500W amp, probably doesn't matter, however, why not plan for the
future? Some day, you may want a bigger amp that will require 240V, so put
it in now.
Barry W2UP
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K4SC
If I were going to the trouble to pull the wire, I'd run 220V. You give
yourself the option of using a heavier amplifier in the future, and less
voltage drop (twice as much on 120V). You can always use the neutral and
one side for 120V now if you really are stuck on it, and use both side of
the line, minus the neutral later if you need it. Remember the amplifier
output is 600 Watts, the input is well over 1KW. What do the lights in your
bathroom do when you or the xyl turn on a hair dryer? Mine dim. Same thing
will happen voltage wise when you key the amp.
Chuck K4SC Crystal River, FL
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ab2tc
Hi,
Absolutely agree, if you are putting in a new circuit, make it 240V. It's
not much more trouble and gives you the choice of local 240 and 120V
outlets.
AB2TC - Knut
PS. S9DX still holding up well here and getting rave reports from points
west.
K4SC wrote:
>
> If I were going to the trouble to pull the wire, I'd run 220V. You give
> yourself the option of using a heavier amplifier in the future, and less
> voltage drop (twice as much on 120V). You can always use the neutral and
> one side for 120V now if you really are stuck on it, and use both side of
> the line, minus the neutral later if you need it. Remember the amplifier
> output is 600 Watts, the input is well over 1KW. What do the lights in
> your bathroom do when you or the xyl turn on a hair dryer? Mine dim.
> Same thing will happen voltage wise when you key the amp.
>
> Chuck K4SC Crystal River, FL
>
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Don Wilhelm
I would not advocate using one side of the 240 volt feed and neutral for
a 120 volt feed. If the need is to run 240 volts to the shack as well
as 120 volts, pull two lines, and put a breaker on each of them. Yes,
your "solution" will work with a 3 wire with ground wiring run, but if
split out to two 120 volt sources, the current on the neutral may exceed
expectations for the wire size used.
A 240 volt AC run can be made with 2 conductors and safety ground. A
120 volt AC run can be made using 2 conductors and safety ground. If
you want 240 volts, start with a 240 volt run from the service panel, if
you want 120 volt service, start with a 120 volt run from the service
panel. Do not mix the two (even though it "works").
Your safety is at stake - stick to the NEC requirements and guidelines.
73,
Don W3FPR
On 2/15/2011 7:25 PM, K4SC wrote:
> If I were going to the trouble to pull the wire, I'd run 220V. You give
> yourself the option of using a heavier amplifier in the future, and less
> voltage drop (twice as much on 120V). You can always use the neutral and
> one side for 120V now if you really are stuck on it, and use both side of
> the line, minus the neutral later if you need it. Remember the amplifier
> output is 600 Watts, the input is well over 1KW. What do the lights in your
> bathroom do when you or the xyl turn on a hair dryer? Mine dim. Same thing
> will happen voltage wise when you key the amp.
>
> Chuck K4SC Crystal River, FL
ab2tc
Hi all,
I was not advocating using the safety ground of the 240V cable for a neutral
return for a 120V outlet (clearly against code). I have not done a a
combined 120/240V run myself but I thought it was possible to get a complete
red/black/white/blank cable to do this in a single run. Rummaging around in
my supply of electrical wire I found a red/black/white piece of cable but
curiously it had no safety ground wire. Anyway, I suppose running two cables
from two breakers is still not too much trouble.
AB2TC - Knut
Don Wilhelm-4 wrote:
>
> Chuck,
>
> I would not advocate using one side of the 240 volt feed and neutral for
> a 120 volt feed. If the need is to run 240 volts to the shack as well
> as 120 volts, pull two lines, and put a breaker on each of them. Yes,
> your "solution" will work with a 3 wire with ground wiring run, but if
> split out to two 120 volt sources, the current on the neutral may exceed
> expectations for the wire size used.
>
> A 240 volt AC run can be made with 2 conductors and safety ground. A
> 120 volt AC run can be made using 2 conductors and safety ground. If
> you want 240 volts, start with a 240 volt run from the service panel, if
> you want 120 volt service, start with a 120 volt run from the service
> panel. Do not mix the two (even though it "works").
>
> Your safety is at stake - stick to the NEC requirements and guidelines.
>
> 73,
> Don W3FPR
> help support this email list: http://www.qsl.net/donate.html
>
>
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Alan Bloom
need a separate safety ground if you want to have any 110V outlets on
the same circuit.
Al N1AL
On Tue, 2011-02-15 at 16:35 -0800, ab2tc wrote:
> Hi,
>
> Absolutely agree, if you are putting in a new circuit, make it 240V. It's
> not much more trouble and gives you the choice of local 240 and 120V
> outlets.
>
> AB2TC - Knut
>
> PS. S9DX still holding up well here and getting rave reports from points
> west.
>
>
> K4SC wrote:
> >
> > If I were going to the trouble to pull the wire, I'd run 220V. You give
> > yourself the option of using a heavier amplifier in the future, and less
> > voltage drop (twice as much on 120V). You can always use the neutral and
> > one side for 120V now if you really are stuck on it, and use both side of
> > the line, minus the neutral later if you need it. Remember the amplifier
> > output is 600 Watts, the input is well over 1KW. What do the lights in
> > your bathroom do when you or the xyl turn on a hair dryer? Mine dim.
> > Same thing will happen voltage wise when you key the amp.
> >
> > Chuck K4SC Crystal River, FL
> >
>
Edward R. Cole
that supplies HV for my 2m-8877 (full QRO). I went to Home Depot and
bought 150-feet of 8-4 cable (actually three #8 awg wires and one #10
solid-conductor safety wire). This runs from my service box to a
small load center (40amp breaker box which I have equipped with a
240-20A and two 120-20A breakers). This does not exceed the 40amp
rating of the box or wiring (35-foot run of 8-4). I run all my shack
power supplies from this source: HVPS on 240vac, 12v-50A PS and
28v-25A PS. The filament transformers and bias supplies. This is
grounded thru a second ground rod outside the shack as well as thru
the 4th safety wire via the service ground.
This lessens the electrical loading on the 120v house circuits in the
bedroom converted to shack. Those circuits power the computer stuff,
lights, antenna rotators, and some test equipment at the work bench,
plus bench 0-30vdc power supply.
73, Ed - KL7UW
------------------------------
Message: 44
Date: Tue, 15 Feb 2011 17:17:42 -0800 (PST)
From: ab2tc <ab...@arrl.net>
Subject: Re: [Elecraft] 120V vs 240V
To: elec...@mailman.qth.net
Message-ID: <1297819062287...@n2.nabble.com>
Content-Type: text/plain; charset=us-ascii
Hi all,
I was not advocating using the safety ground of the 240V cable for a neutral
return for a 120V outlet (clearly against code). I have not done a a
combined 120/240V run myself but I thought it was possible to get a complete
red/black/white/blank cable to do this in a single run. Rummaging around in
my supply of electrical wire I found a red/black/white piece of cable but
curiously it had no safety ground wire. Anyway, I suppose running two cables
from two breakers is still not too much trouble.
AB2TC - Knut
73, Ed - KL7UW, WD2XSH/45
======================================
BP40IQ 500 KHz - 10-GHz www.kl7uw.com
EME: 144-1.4kw*, 432-100w, 1296-testing*, 3400-winter?
DUBUS Magazine USA Rep dubu...@hotmail.com
======================================
*temp not in service
Paul Christensen
> bedroom converted to shack. Those circuits power the computer stuff,
> lights, antenna rotators, and some test equipment at the work bench,
> plus bench 0-30vdc power supply.
Many good suggestions here. If for no other reason, running dedicated
branch circuits into the shack will often eliminate light dimming. My shack
occupies a spare bedroom and the 120V receptacles were at the end of a
shared branch with an adjacent room. Keying at 100W would cause the room
lights to noticeably dim. Now add a 500W solid-state amp to that circuit
and not only will the lights dim, but voltage regulation on the branch
suffers.
This is one of those projects where it will often pay off to run multiple
branch circuits into the shack. If you need one, it takes little effort and
cost to pull a couple more. I did all my attic work in the middle of the
hot Florida summer. I tried to start early and finished by 11am when temps
really start to climb. The job was split into two days but there's now two
separate 120V branch circuits into the shack that only power equipment. A
30A, 240AC 4-wire circuit was pulled ten years ago. I now wish I had
pulled a few more to have dedicated 240V receptacles for each amp.
It's easy to quickly run out of panel space. I had already maxed-out a
sub-panel and for better or worse, I used a tandem breaker for the two 20A
shack feeds since I had a single remaining position available in the sub
panel.
Paul, W9AC
Scott Ellington
Keep in mind that 500 W output requires about 1 kW input, that the power factor of the power supply is considerably less than 1, and that the high peak currents make the effects of line voltage drop even worse. When calculating effective line drop for the KPA500, I would use something like 2 kVA, about 17 A at 120 V. The above example corresponds to a run of 220 feet of AWG 12 (440 feet total), admittedly a very long run.
Bottom line: If you are adding wiring, use 240 V. Run the amplifier on 120 V only if you have no choice, or if the run from the distribution panel is under about 50 feet.
Scott K9MA
On Feb 15, 2011, at 6:25 PM, K4SC wrote:
> If I were going to the trouble to pull the wire, I'd run 220V. You give
> yourself the option of using a heavier amplifier in the future, and less
> voltage drop (twice as much on 120V).
Scott Ellington
Madison, Wisconsin
USA
Robert Harmon
having to reset circuit breakers a few times decided I had to do something ! Yes, some work involved running the romex
cable thru the attic, etc but well worth it.
Bob
K6UJ
Bob
K6UJ
Phil & Debbie Salas
However, the KPA500 only draws about 9-amps at 120VAC. While I could set it up for 240VAC (and I probably will one of these days), at 9-amps there is no lamp flickering in my shack, no noticable AC voltage drop, and I can put out the full 500 watts with no problem.
Phil - AD5X
Paul Christensen
>supply, and the ALS-600 draws very close to 15 amps with the switcher. As
>my shack is diagonally across the house from the breaker panel, I was
>actually seeing 20VAC drop in the wiring. This caused two problems: Lots
Phil, was the light dimming occurring before or after your pulled the 240V
branch into the shack? If it was after, I'm curious why the lights would
dim if they're on a 120V branch while the amp is on its own 240V branch.
Seems if they're dimming after pulling the new 240V circuit, then the
dimming is the result of the TRX current and not the amp? Tnx!
Paul, W9AC
Phil & Debbie Salas
the ALS-600 on 120VAC. No problem on 240VAC. However, no problem at all
when running the KPA500 on 120VAC.
Phil - AD5X
Lew Phelps K6LMP
I am assuming that with a 15 amp breaker the circuit is wired (per the National Electrical Code requirements) with 14 gauge copper wire. A voltage drop of 20 VAC, or 16.3%, would be consistent with a wire run of 250 feet. Even running along the two legs of a triangle (not the more direct hypotenuse), your wire run is probably no more than 60 or so feet, unless you own a very large house. The voltage drop should be 3 or 4 volts at 15 amps, not 20 volts. Either there's a connection in the circuit that is creating some resistance, or the wiring is undersized (unlikely).
If you have an oxidized or otherwise "non-clean" connection (such as a wire that has been arcing under the connecting screw or a loose connection inside a wire nut) you have a real fire hazard. I suggest a careful inspection of every joint in the wire run from the breaker to the outlet. If you don't see anything obvious that you can correct, call an electrician. House wiring is quite different (mechanically, not electrically) from the sort of wiring we're accustomed to dealing with inside a radio chassis. Unless you know for sure what you're doing, and know the NEC requirements, this is a job best left to professionals.
Lew K6LMP
VTuff...@aol.com
you should all emigrate to the UK!
We have 240V AC as standard ;-)
73's
Vic
G7PYR
Edward R. Cole
I used to run a smaller PS that provided 2500v at 400mA = 1000w dc
input with 600w RF out on my 2m-8877. That PS ran on 120vac and drew
8.3 amps on ordinary house wiring and I saw some flicker in the
lights on CW. I don't recall what the voltage sag was.
Now I run 3700v at 720 mA = 2664w dc (1400w RF) which represents a
10.9 amp load on 244vac (my line voltage). I see about 2-3 volts
line -voltage sag so that is 33w dissipation in the 8-4 wiring. If I
had tried running with 120vac the load would be 21.8 amps which would
exceed the rating of the wiring and likely trip breakers. The power
supply is capable or 1.5amps dc load so represents a max load of 5kW
and that hits over 20A which is my current breaker rating. Of course
this would produce 2500w RF which exceeds legal level by a lot.
Important stuff to consider when running significant RF power. The
KPA-500 will likely run on 120vac with no problem but better if run on 240v.
------------------------------
Message: 16
Date: Wed, 16 Feb 2011 10:35:27 -0600
From: Scott Ellington <sdel...@facstaff.wisc.edu>
Subject: Re: [Elecraft] 120V vs 240V
To: Elecraft Reflector <elec...@mailman.qth.net>
Message-ID: <74E5832A-97F4-494F...@facstaff.wisc.edu>
Content-Type: text/plain; CHARSET=US-ASCII
Actually, the percentage voltage drop at 120 V is FOUR times that at
240 V. (For the same power, wire gauge and length.) Since the
KPA500, like most tube-type amplifiers, uses an unregulated power
supply, the extra drop can significantly reduce output. For example,
suppose the amplifier can put out 500 W with a perfectly regulated
input of 120 or 240 V. Say the line voltage, at 240 V, drops 6 volts
at full output. That's a 2.5 percent drop, which reduces RF output
by about 5 percent, to about 475 W. At 120 V, the drop is 12 volts,
10 percent, which reduces the output by about 20 percent, to about
400 W. You just lost 75 more Watts, each of which cost you $4.
Keep in mind that 500 W output requires about 1 kW input, that the
power factor of the power supply is considerably less than 1, and
that the high peak currents make the effects of line voltage drop
even worse. When calculating effective line drop for the KPA500, I
would use something like 2 kVA, about 17 A at 120 V. The above
example corresponds to a run of 220 feet of AWG 12 (440 feet total),
admittedly a very long run.
Bottom line: If you are adding wiring, use 240 V. Run the amplifier
on 120 V only if you have no choice, or if the run from the
distribution panel is under about 50 feet.
Scott K9MA
73, Ed - KL7UW, WD2XSH/45
======================================
BP40IQ 500 KHz - 10-GHz www.kl7uw.com
EME: 144-1.4kw*, 432-100w, 1296-testing*, 3400-winter?
DUBUS Magazine USA Rep dubu...@hotmail.com
======================================
*temp not in service
Don Wilhelm
wiring carefully.
If the receptacles are wired using the "backstab" holes rather then
having the wires secured under the screws, that is a possible cause, as
are loose screws in the receptacles.
73,
Don W3FPR
On 2/16/2011 1:04 PM, Lew Phelps K6LMP wrote:
> Phil, the 20 VAC drop that you describe for a 15 amp draw on a 120 VAC circuit strongly suggests that something is wrong with the wiring.
>
Scott Ellington
Scott K9MA
Scott Ellington
Madison, Wisconsin
USA
______________________________________________________________
Ron D'Eau Claire
work just fine with the KPA500. I am testing a KPA500 on a 120V, 20 amp
circuit that is fully 50 feet from the breaker panel.
Yes, there is significant droop in the mains voltage when I key down at 500
watts output, but the KPA500 has internal transformer taps that can be
chosen to provide the correct voltage under such conditions. There is a
limit to the droop allowed as internal voltages in the KPA500 rise when not
transmitting (or running at reduced power). The tap is chosen to stay within
the upper limit "key up".
I submit that my situation is just about worst case - considering that it's
only a 20 A (instead of a 30A) circuit and the 50-foot distance from the
breaker panel involved, yet I easily found a tap combination that provided
the voltage for full output without exceeding the upper limit key up.
I have a home built about 30 years ago, and one thing I have noticed that
applies here. Commonly used power outlets wear out. Long ago I noticed that
I could hear that our vacuum cleaner (which draws 12 amps at 120V) ran more
slowly on some outlets than others. Investigation showed that the springs in
the outlet itself were weak after many years of having plugs pushed in and
pulled out. As they weakened, the contact with the plug got loose, causing
heating and further weakening of the springs (there's a reason outlets are
mounted in fire-resistant enclosures!).
Replacing the outlets cured the problem. It's a simple job for most. Just be
certain you have the circuit off at the breaker panel, and everyone in the
house knows what you are doing so no one flips it on while you are working
(professionals lock the main breaker panel shut and put a big sign on it
while working on a circuit elsewhere).
Ron AC7AC
-----Original Message-----
From: elecraft...@mailman.qth.net
[mailto:elecraft...@mailman.qth.net] On Behalf Of Edward R. Cole
Sent: Wednesday, February 16, 2011 10:47 AM
To: Elec...@mailman.qth.net
Subject: [Elecraft] 120V vs 240V
Important reasons for running HP amps with 240vac.
I used to run a smaller PS that provided 2500v at 400mA = 1000w dc
input with 600w RF out on my 2m-8877. That PS ran on 120vac and drew
8.3 amps on ordinary house wiring and I saw some flicker in the
lights on CW. I don't recall what the voltage sag was.
Now I run 3700v at 720 mA = 2664w dc (1400w RF) which represents a
10.9 amp load on 244vac (my line voltage). I see about 2-3 volts
line -voltage sag so that is 33w dissipation in the 8-4 wiring. If I
had tried running with 120vac the load would be 21.8 amps which would
exceed the rating of the wiring and likely trip breakers. The power
supply is capable or 1.5amps dc load so represents a max load of 5kW
and that hits over 20A which is my current breaker rating. Of course
this would produce 2500w RF which exceeds legal level by a lot.
Important stuff to consider when running significant RF power. The
KPA-500 will likely run on 120vac with no problem but better if run on 240v.
Ron D'Eau Claire
Us OT's remember when almost all automobiles (including my British MGA) had
6-volt batteries. As more electronics were added to cars it eventually
forced a shift to 12 VDC to avoid requiring huge cables attached to gigantic
terminals to avoid excessive resistive losses. (A lot of us working in
aerospace wondered why they didn't just jump to the 24VDC system already in
use then by the military and aircraft.)
Someday Americans will make the shift to 240VAC throughout our homes.
Virtually every home built in he uSA since the 1970's has 240V circuits
supplying major appliances: ovens, cook top, clothes dryer, air
conditioners, etc., and in many areas such as where I live supplied by wind
and hydroelectric power, electric central heating furnaces.
Nowadays we all have a myriad of multi-voltage devices in our homes. This HP
computer workstation is 120/240V as is my cell phone and other chargers,
various power supplies, my laptop computers, etc. Just about the only thing
that requires 120 VAC in our house are lights and a 20+ year old TV set.
Our common wall switches and outlets are already rated for 240V although a
different style outlet/plug style is commonly used to avoid confusion.
It can't be too long before we see the last few electrical devices - lights,
etc. - switch to 240V.
Ron AC7AC
Don Cunningham
Don Cunningham
something interesting in doing some "remodeling" and replacing receptacles.
The old ones were ivory, and with the new white trim, I had to please the
XYL, hi. Anyway, since my wiring days in the sixties, I have avoided the
"backstab" type receptacle myself, knowing that spring HAD to wear out over
the years. I found some receptacles at Lowe's, made by Cooper Industries
that had the "backstab" feature. I was going to wrap the wire under the
screws as I always have BUT these new back entry plugs now use the screw on
the side to run a clamping mechanism against the wire, making a really good
connection!! If one looks at the new plugs, you may be pleasantly surprised
to find this new feature (maybe old by now, but my first experience with
it). I did a "test room" with that method, but will do the rest of the
place the old fashioned way, hi.
By the way, off topic, but I invested in one of the IBM refurbished
computers you recommended and LOVE it!! It looks like a new machine, has a
LOT of memory and a HUGE hard drive, 2 serial ports and a host of USB ones,
3 1/2" floppy dirve, quiet fan and just works well in the shack. Thanks for
making the recommendation. With the "extras" on it, I still didn't spent
$300, which is phenomenal to me.
73,
Don, WB5HAK
Roger D Johnson
> Guys,
> you should all emigrate to the UK!
>
> We have 240V AC as standard ;-)
>
> 73's
>
> Vic
> G7PYR
> ______________________________________________________________
>
>
were 10 Hz short.
73, Roger
Paul Christensen
Good point, Don. For me, it's hard to believe that using "back-stab"
receptacle connections is still NEC/UL compliant. At least in recent years,
use is limited to only #14 AWG, meaning (thankfully), they cannot be used on
a feeder or branch circuit above 15A. If I had a home using those, I would
take the time to rewire every receptacle and use the screw terminals
instead.
For just a bit more cost over the 50-cent contractor-grade receptacles,
industrial-grade receptacles can be purchased. These receptacles may look
like they have back-stab pin holes but in fact use a clamp together with the
side terminal screw to solidly hold the conductor in place. Better wire
grip, safer than back-stabs, and install quickly without the need for a
J-hook around the screw terminal.
Paul, W9AC
Don Wilhelm
Yes Don Cunningham mentioned that he bought some home receptacles with
that type clamp. I have previously only seen them in industrial
applications - they make very solid connections.
I had to grin a bit at the electrician that wired a new rental house for
us (I was not permitted to do my own work because I would not live in it
for a year) and I specified #12 wire for all the receptacles, thus
preventing the use of the backstab holes.
All the receptacles in my home are also #12 wire to keep the voltage
drop down, and the screws are well tightened (I had to check the ones
the XYL connected)
73,
Don W3FPR
Jeff Cochrane - VK4BOF
Jeff Cochrane - VK4BOF
Innisfail, QLD, Australia
Elecraft K3# 4257 + PR6 - K144XV = multiband goodness!
----- Original Message -----
From: VTuff...@aol.com
To: Elec...@mailman.qth.net
Sent: Thursday, February 17, 2011 4:07 AM
Subject: Re: [Elecraft] 120V vs 240V
ab2tc
Hi,
Agree, those "backstab" holes are a fire waiting to happen. As I renovated
each room in my house I always replaced each outlet and switch and wrapped
the wires around the screw. I have never used any of those the "industrial
grade" receptacles though.
AB2TC - Knut
P.B. Christensen wrote:
>
>> If the receptacles are wired using the "backstab" holes rather then
>> having the wires secured under the screws, that is a possible cause...
>
> Good point, Don. For me, it's hard to believe that using "back-stab"
> receptacle connections is still NEC/UL compliant. At least in recent
> years,
> use is limited to only #14 AWG, meaning (thankfully), they cannot be used
> on
> a feeder or branch circuit above 15A. If I had a home using those, I
> would
> take the time to rewire every receptacle and use the screw terminals
> instead.
>
> For just a bit more cost over the 50-cent contractor-grade receptacles,
> industrial-grade receptacles can be purchased. These receptacles may look
> like they have back-stab pin holes but in fact use a clamp together with
> the
> side terminal screw to solidly hold the conductor in place. Better wire
> grip, safer than back-stabs, and install quickly without the need for a
> J-hook around the screw terminal.
>
> Paul, W9AC
>
>
>
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Phil & Debbie Salas
the wires secured under the screws, that is a possible cause..."
Everything in the house was originally wired using the "backstab" holes in
the switches and sockets. I've been gradually replacing them over the
years. My ham shack is diagonally opposite the breaker-box, with (I
estimate) 80-feet of #14 wire running through I don't know how many outlets
and switches to get there. The ALS-600 switcher draws right at about
15-amps at 120VAC (the ALS-600 unregulated linear supply draws about 13 amps
at 120VAC). As the AC voltage drops, the AC current increases (the switcher
keeps the FET drain voltage constant). So key down I was drawing in excess
of 15 amps. That's why I put in a 240VAC line.
But I've been doing all my KPA500 testing on the 120VAC line and it works
great - the KPA500 only draws 9-amps at 120VAC (low enough for my 27 year
old house wiring). I'll eventually put it on the 240VAC line though.
Phil - AD5X
Jeff Cochrane - VK4BOF
I believe that NZ has slightly less draconian laws that allow some limited house wiring mods to be done (and your allowed to put plugs on leads!) but over here any household electrical work must be done by a suitably licenced electrician.
Damned silly rule if you ask me.
Jeff Cochrane - VK4BOF
Innisfail, QLD, Australia
Elecraft K3# 4257 + PR6 - K144XV = multiband goodness!
----- Original Message -----
From: ab2tc
To: elec...@mailman.qth.net
Sent: Thursday, February 17, 2011 7:35 AM
Subject: Re: [Elecraft] 120V vs 240V
ab2tc
Hi,
I was born in Norway and lived there until emigrating here as a young adult.
Norway also has 240V as the only electrical domestic voltage. It's used for
for everything from lamps to heavy duty kitchen stoves or clothes dryers. In
Norway any work on the electrical wiring in a dwelling had to be done by a
certified (and expensive) electrician. Supplies such as wire, receptacles
and switches were simply unavailable to the general public. I don't know,
but suspect that the same may apply to the UK and Australia. While I agree
that the 240V system is technically superior to the 115/230V system used in
North America, I do enjoy the ability to do my own work on the wiring. It
certainly saves a lot of money.
AB2TFC - Knut
Jeff Cochrane - VK4BOF wrote:
>
> Ditto for Australia.
>
>
> Jeff Cochrane - VK4BOF
> Innisfail, QLD, Australia
> Elecraft K3# 4257 + PR6 - K144XV = multiband goodness!
>
> ----- Original Message -----
> From: VTuff...@aol.com
> To: Elec...@mailman.qth.net
> Sent: Thursday, February 17, 2011 4:07 AM
> Subject: Re: [Elecraft] 120V vs 240V
>
>
> Guys,
> you should all emigrate to the UK!
>
> We have 240V AC as standard ;-)
>
> 73's
>
> Vic
> G7PYR
> <snip>
>
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Doug Faunt N6TQS +1-510-655-8604
receptacles -- with 240 volts. The receptacles that I looked at were
all rated at 10A.
I think the US is paying the price of being "early-adopters".
And I don't think the US standard will change- the current (no pun
intended) system is too well entrenched, and the costs would outway the
very real advantages. Note that the Japanese use very similar voltage
and receptacles.
73, doug
On 16-Feb-11 13:32, Jeff Cochrane - VK4BOF wrote:
> Ditto for Australia.
>
David Christ
a heavy feeder ta sub panel as it is to pull a couple of branch
circuits.
In my unfinished basement there were only three 15 amp 110 v
circuits. Furnace, sump pump and lights. The main entry was in the
garage. When I finished the basement there was no way to run wires
from the garage to the basement. I pulled a run of #6/3 w/ground to
a sub panel near the furnace. I moved all the old basement circuits
to the new panel. This allowed me to install a new 220 v breaker in
the main entry to feed the new sub panel. There are plenty of slots
in the new sub panel to make all the 110 and 220 v circuits I need.
I used #6 which is oversize to make the voltage variation from no
load to full load as little as possible. The value of the breakers
in the new panel can add up to more that the capacity of the cable
you just ran. The breaker in the main panel protects the feeder.
The breakers in the sub panel are sized to protect the final branch
circuits.
If your new wiring only supplies the shack you might wish to consider
using a main breaker rather than a main lug box for the sub panel.
Maybe it is not so important now as when we had so much high voltage
running around, but the old safety recommendation was to have the
wiring set up so that a single switch would kill all the power in the
shack.
Some notes: the bare grounding wire is connected to the box itself.
The white grounded (neutral) wire is supposed to be connected to the
grounded wire only at the main entry and not in the sub panel. This
has been code for a long time. Also the rules for wring in bedrooms
and basements has been changing over the last two or three editions
of the electrical code.
There are probably professionals on the list who can correct any
errors I have made and are more qualified on the details than I am.
David K0LUM
At 3:25 AM -0900 2/16/11, Edward R. Cole wrote:
>I recently wired my ham shack for 240vac for supplying my 4500w HVPS
>that supplies HV for my 2m-8877 (full QRO). I went to Home Depot and
>bought 150-feet of 8-4 cable (actually three #8 awg wires and one #10
>solid-conductor safety wire). This runs from my service box to a
>small load center (40amp breaker box which I have equipped with a
>240-20A and two 120-20A breakers). This does not exceed the 40amp
>rating of the box or wiring (35-foot run of 8-4). <snip>
>
>73, Ed - KL7UW
Dave KQ3T
preference was Triumphs, however, not MGs.)
73,
Dave KQ3T
On 2/16/2011 2:13 PM, Ron D'Eau Claire wrote:
> As does much of Europe (just next door to you :-)
>
> Us OT's remember when almost all automobiles (including my British MGA) had
> 6-volt batteries. As more electronics were added to cars it eventually
> forced a shift to 12 VDC to avoid requiring huge cables attached to gigantic
> terminals to avoid excessive resistive losses. (A lot of us working in
> aerospace wondered why they didn't just jump to the 24VDC system already in
> use then by the military and aircraft.) ...
Phil Kane
> Not only were they 6V, but positive ground, if I recall
> correctly. (My preference was Triumphs, however, not MGs.)
IIRC all of the British 6 volters were positive ground. When
I needed an isolation block (2 big diodes on a heat sink) to
power my K2 from either of two 12V sources, I had to get the
British version of a dual-battery charger.
Several decades ago I had a 6V (neg ground) VW beetle that I
converted to 12V to be able to run my 12V radio equipment
(pre-Elecraft). I was able to get all of the necessary
components including a real alternator at a VW "custom" parts
place, and I replaced everything except the starter motor. The
engine turned over very quickly running the 6V motor on 12V!
-- 73 de K2ASP - Phil Kane
Elecraft K2/100 s/n 5402
Don Wilhelm
I am stretching my memory a bit, but I "think" I remember my 1951 Ford
(my first car) had a 6 volt positive ground system as well - even if my
memory is "fuzzy", I do know there was one domestic car manufacturer
that used a 6 volt positive ground.
My 1973 MG Midget was 12 volts negative ground.
73,
Don W3FPR
Lew Phelps K6LMP
Someone raised the question why the auto industry didn't just go to 24 volts. The answer is battery size. Trucks, boats, and planes are mostly 24 volts, but they mostly have more room "under the hood" than most autos. There were only a couple of standard cell sizes available in lead acid batteries, and scaling up to 24VDC even with the smallest of them required dedicating a lot of space to batteries. Those older vehicle engines were not very compact or efficient, by today's standards. There's room under the hood of my Hudson for a 12 volt battery, but not for twice that volume. Most vehicles that have 24VDC systems get there by strapping a pair of 12 volt batteries in series, rather than by employing a single (and more compact) 24 volt battery. That's the situation with a military surplus vehicle I also own, a 1975 Pinzgauer, which serves as a great platform for my VHF/UHF rover contesting station (which is based on my K3, and thus qualifies this post not OT...;-) )
Lew K6LMP
On Feb 16, 2011, at 4:33 PM, Don Wilhelm wrote:
> Phil,
>
> I am stretching my memory a bit, but I "think" I remember my 1951 Ford
> (my first car) had a 6 volt positive ground system as well - even if my
> memory is "fuzzy", I do know there was one domestic car manufacturer
> that used a 6 volt positive ground.
>
> My 1973 MG Midget was 12 volts negative ground.
>
> 73,
> Don W3FPR
FredJensen
> I own a 1929 Hudson Town Sedan. Its OEM electrical system was 6 volt positive ground. Later Hudsons were 12 volt negative ground. From my contact with the old car restoration community, my sense is that in the early years (up to about 1950) the industry was about evenly split between positive and negative ground. They finally standardized on 12 volt negative, more or less in the 60s.
positive ground, fairly beat up, bad brakes. I ran a 40m ARC-5 off of a
vibrator power supply with a Gonset "converter" feeding the AM radio
with an outboard BFO for CW. The vehicles we had in SE Asia in the US
military were mainly 12V by 1964. Our multi-fuel 5-ton trucks were
24V, I think to get the engines started.
Stupid question: I was under the impression that the KPA500 was solid
state, no-tune. A couple of references on this long "Voltage Thread"
have caused me to wonder. Fact would be welcome.
73,
Fred K6DGW
Auburn CA
PS S9DX is S9 on 14011 as I type, up 3 got him for me, they leave
tomorrow I think
Ron D'Eau Claire
design engineers) is that the KPA500 is solid state "FIXED TUNE" - which is
true of most, if not all, Ham amplifiers on the market.
That means that it works at peak efficiency at some point in each band and
the efficiency starts to drop off above and below that frequency. It'll do
full power output across the whole range of any Amateur band, of course, but
the current demanded will rise somewhat at the limits, even feeding a 50 ohm
resistive load.
Ron AC7AC
-----Original Message-----
From: elecraft...@mailman.qth.net
[mailto:elecraft...@mailman.qth.net] On Behalf Of FredJensen
Sent: Wednesday, February 16, 2011 4:57 PM
To: Elecraft Reflector
Subject: Re: [Elecraft] 120V vs 240V
On 2/17/2011 12:45 AM, Lew Phelps K6LMP wrote:
Stupid question: I was under the impression that the KPA500 was solid
state, no-tune. A couple of references on this long "Voltage Thread"
have caused me to wonder. Fact would be welcome.
73,
Fred K6DGW
Auburn CA
R. Kevin Stover
"Don Cunningham" <do...@martineer.net> wrote:
> I guess I'm getting old. Sorry about the blank message!! Don, I
> found something interesting in doing some "remodeling" and replacing
> receptacles. The old ones were ivory, and with the new white trim, I
> had to please the XYL, hi. Anyway, since my wiring days in the
> sixties, I have avoided the "backstab" type receptacle myself,
> knowing that spring HAD to wear out over the years. I found some
> receptacles at Lowe's, made by Cooper Industries that had the
> "backstab" feature. I was going to wrap the wire under the screws as
> I always have BUT these new back entry plugs now use the screw on the
> side to run a clamping mechanism against the wire, making a really
> good connection!! If one looks at the new plugs, you may be
> pleasantly surprised to find this new feature (maybe old by now, but
> my first experience with it). I did a "test room" with that method,
> but will do the rest of the place the old fashioned way, hi.
Don and all.
Our house, a 1972 vintage four level split, was full of back-stab
receptacles. We had one fail in an upstairs bedroom so after the
electrician left I went down to the hardware barn and purchased a box
or two of of the receptacle that Don Cunningham references.
I just finished changing out the last two this last weekend.
I did a little test. I wrapped a length of 14/2 Romex around my bench
vise in the garage and clamped it down tight. Connected the other
stripped ends to one of the new receptacles using the "back-stab+screw"
connection and started pulling.
As expected the wire stayed put and more importantly didn't let go when
there was slack on the cable after the pulling exercise.
This house has all new receptacles now. Now all I have to worry about
is the 39 year old wiring and the "creative" wiring the builder did
when he put this thing up.
Lets just say the kitchen has all new Romex in it after a kitchen
remodel exposed the fact that the builder ran all of the Romex for the
kitchen through the ceiling soffits (considered living space by our
code) rather than the walls.
--
R. Kevin Stover
AC0H
Bob Nielsen
Bob N7XY
Eric Swartz - WA6HHQ, Elecraft
73, Eric
Elecraft list moderator
David Christ
states outlawed 24 volt systems in autos after people bought surplus
aircraft landing lights which were super bright but also wide beam.
They blinded oncoming drivers.
David K0LUM
At 4:45 PM -0800 2/16/11, Lew Phelps K6LMP wrote:
>
>Someone raised the question why the auto industry didn't just go to
>24 volts. The answer is battery size. Trucks, boats, and planes
>are mostly 24 volts, but they mostly have more room "under the hood"
>than most autos. There were only a couple of standard cell sizes
>available in lead acid batteries, and scaling up to 24VDC even with
>the smallest of them required dedicating a lot of space to
>batteries. Those older vehicle engines were not very compact or
>efficient, by today's standards. There's room under the hood of my
>Hudson for a 12 volt battery, but not for twice that volume. Most
>vehicles that have 24VDC systems get there by strapping a pair of 12
>volt batteries in series, rather than by employing a single (and
>more compact) 24 volt battery. That's the situation with a military
>surplus vehicle I also own, a 1975 Pinzgauer, which serves as a
>great platform for my VHF/UHF rover contesting station (which is
>based on my K3, and thus qualifies this post not OT...;-) )
>
>Lew K6LMP
W8JH
Thanks Eric,
My question about 120 vs. 240 was asked and answered almost
a month ago. I was surprised to see it resurrected and the number of
replies lately to my email (about cars, houses etc.) was astounding.
Keep up the good work herding this amazing group.
73,
Joe W8JH
K3 1713
From: Eric Swartz - WA6HHQ, Elecraft [via Elecraft]
[mailto:ml-node+6037111-...@n2.nabble.com]
Sent: Thursday, February 17, 2011 1:41 PM
To: W8JH
Subject: Re: 120V vs 240V [END of Thread]
Let's end the 120V vs 240V thread for now. Its getting way too long ;-)
73, Eric
Elecraft list moderator
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