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[KPA500]KPA500 power cord question

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K2GN

[KPA500]KPA500 power cord question

GA,

I am in the process of rebuilding my shack and planning for the future.

I will order a KPA500 and want to be ready for it power wise.

I want to run it on 220V as it is available in a nearby panel.

Question is:

The manual states for 220V operation I would need an adaptor or new plug on
the power cord.

Is this a choice that I have as far as wall outlet and matching plug? If so,
no problem, my electrician can fix it up.

If it's some special, I need specs for it.

Thank you in advance,

de K2GN - Larry <mailto:[hidden email]> - http://k2gn.com <http://k2gn.com/>

K3 S/N - 3278 P3 S/N - 51

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Iain MacDonnell - N6ML-2

Re: [KPA500]KPA500 power cord question

On Tue, May 3, 2011 at 5:59 PM, K2GN <[hidden email]> wrote:

k2ue

Re: [KPA500]KPA500 power cord question

Currently the nominal voltages for most US power companies is 240/120V single phase, although in some areas 120/208V 3-phase is
common, with 120V outlets being served by any one phase, and 208V circuits being fed across any 2 phases. Accordingly, most US
appliances either have specific performance ratings that differ slightly for 208V vs. 240V (resistive heaters and A/C compressors
are a common example), or have power supply taps to accommodate either (common in electronic equipment).

The major advantage of 240V operation is improved voltage regulation: the same circuit, fed with the same wire (such as a common
20A 12 gauge circuit), will have the same resistance in either case. But since the current is roughly half at 240V, the I*R drop
will be half, which will be 1/4 the relative amount compared to the doubled voltage. You can see that unregulated supplies will
perform much better, if the current is high enough for line drop to be noticeable.

US plugs and receptacles are rated for either 125V (max) or 250V (max), and are non-mating between voltages, for safety. However
20A receptacles of ether voltage will accept 15A plugs of the same voltage, so the ideal hamshack receptacle for a linear is a
250V/20A receptacle wired to a 240V or 208V 20A circuit, which will also accept 15A 250V plugs, the smallest and most common type.
Since 20A wiring and circuit breakers cost very little more than 15A, there is little point in installing 15A circuits, unless it is
advantageous to use existing wiring in an house or building where new wire installation is difficult. Please note that if you
convert an existing 120V wire run to 208 or 240V, you are obligated by code (and common sense) to remark the white (formerly
neutral) wire with red paint or tape at all points of access, to identify as a "hot" lead. And receptacle ratings should never
exceed the rating of the circuit they are on: never use a 20A receptacle on a 15A circuit.

In the specific case of the KPA500, it requires 1000VA (volt-amperes), so that is 8.3A at 120V, 4.8A at 208V, or 4.2A at 240V. 8.3A
is not a particularly heavy load for a 20A circuit, but if it is a 15A circuit or is also loaded with all the other hamshack gear,
then either a separate 120V circuit for the linear, or preferably a 240V circuit is a good idea.

_____________________
Clyde Washburn, K2UE
82 Lasalle Pkwy
Victor, NY 14564-9610
585-317-7006
[hidden email]

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of iain macdonnell - N6ML
Sent: Tuesday, May 03, 2011 2:21 PM
To: K2GN
Cc: Elecraft - K3
Subject: Re: [Elecraft] [KPA500]KPA500 power cord question

On Tue, May 3, 2011 at 5:59 PM, K2GN <[hidden email]> wrote:

I think that's left as an exercise for you ... find a heavy computer power cord, cut the plug off, and install one that matches your
outlet .. or install a matching pair that you like.

I'd be interested to hear about benefits (if any) of running the
KPA-500 on 220V vs 110V (in the US)......

~iain / N6ML
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Iain MacDonnell - N6ML-2

Re: [KPA500]KPA500 power cord question

Hi Clyde,

Can we boil this down a bit? Would a 220/240V input get me more power
out of the KPA-500 (vs. a 20A 110V circuit, say)? A cleaner signal?
Less input power consumed? Anything discernible?

~iain / N6ML

On Tue, May 3, 2011 at 7:21 PM, Clyde Washburn <[hidden email]> wrote:

> Currently the nominal voltages for most US power companies is 240/120V single phase, although in some areas 120/208V 3-phase is
> common, with 120V outlets being served by any one phase, and 208V circuits being fed across any 2 phases. Accordingly, most US
> appliances either have specific performance ratings that differ slightly for 208V vs. 240V (resistive heaters and A/C compressors
> are a common example), or have power supply taps to accommodate either (common in electronic equipment).
>
> The major advantage of 240V operation is improved voltage regulation: the same circuit, fed with the same wire (such as a common
> 20A 12 gauge circuit), will have the same resistance in either case. But since the current is roughly half at 240V, the I*R drop
> will be half, which will be 1/4 the relative amount compared to the doubled voltage. You can see that unregulated supplies will
> perform much better, if the current is high enough for line drop to be noticeable.
>
> US plugs and receptacles are rated for either 125V (max) or 250V (max), and are non-mating between voltages, for safety. However
> 20A receptacles of ether voltage will accept 15A plugs of the same voltage, so the ideal hamshack receptacle for a linear is a
> 250V/20A receptacle wired to a 240V or 208V 20A circuit, which will also accept 15A 250V plugs, the smallest and most common type.
> Since 20A wiring and circuit breakers cost very little more than 15A, there is little point in installing 15A circuits, unless it is
> advantageous to use existing wiring in an house or building where new wire installation is difficult. Please note that if you
> convert an existing 120V wire run to 208 or 240V, you are obligated by code (and common sense) to remark the white (formerly
> neutral) wire with red paint or tape at all points of access, to identify as a "hot" lead. And receptacle ratings should never
> exceed the rating of the circuit they are on: never use a 20A receptacle on a 15A circuit.
>
> In the specific case of the KPA500, it requires 1000VA (volt-amperes), so that is 8.3A at 120V, 4.8A at 208V, or 4.2A at 240V. 8.3A
> is not a particularly heavy load for a 20A circuit, but if it is a 15A circuit or is also loaded with all the other hamshack gear,
> then either a separate 120V circuit for the linear, or preferably a 240V circuit is a good idea.
>
> _____________________
> Clyde Washburn, K2UE
> 82 Lasalle Pkwy
> Victor, NY 14564-9610
> 585-317-7006
> [hidden email]
>
> -----Original Message-----
> From: [hidden email] [mailto:[hidden email]] On Behalf Of iain macdonnell - N6ML
> Sent: Tuesday, May 03, 2011 2:21 PM
> To: K2GN
> Cc: Elecraft - K3
> Subject: Re: [Elecraft] [KPA500]KPA500 power cord question
>
> On Tue, May 3, 2011 at 5:59 PM, K2GN <[hidden email]> wrote:
>> GA,
>>
>> I am in the process of rebuilding my shack and planning for the future.
>>
>> I will order a KPA500 and want to be ready for it power wise.
>>
>> I want to run it on 220V as it is available in a nearby panel.
>>
>> Question is:
>>
>> The manual states for 220V operation I would need an adaptor or new
>> plug on the power cord.
>>
>> Is this a choice that I have as far as wall outlet and matching plug?
>> If so, no problem, my electrician can fix it up.
>>
>> If it's some special, I need specs for it.
>
> I think that's left as an exercise for you ... find a heavy computer power cord, cut the plug off, and install one that matches your
> outlet .. or install a matching pair that you like.
>
> I'd be interested to hear about benefits (if any) of running the
> KPA-500 on 220V vs 110V (in the US)......
>
> ~iain / N6ML
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>

k2ue

Re: [KPA500]KPA500 power cord question

Probably the primary benefit would be a slightly cleaner signal, due to more headroom in the PA at peak current, or slightly more
power output for the same distortion level. The difference would not be huge at the 500W level -- were we talking 1KW or 1.5KW the
effect is usually more pronounced. A lot also depends on local conditions: if you share a pole transformer with many other homes,
and/or experience poor line regulation during heating or A/C weather, then the higher voltage is you best defense, by reducing the
voltage drops within your own home.

_____________________
Clyde Washburn, K2UE
82 Lasalle Pkwy
Victor, NY 14564-9610
585-317-7006
[hidden email]

-----Original Message-----
From: [hidden email] [mailto:[hidden email]] On Behalf Of iain macdonnell - N6ML
Sent: Tuesday, May 03, 2011 3:44 PM
To: Clyde Washburn
Cc: K2GN; Elecraft - K3
Subject: Re: [Elecraft] [KPA500]KPA500 power cord question

Hi Clyde,

Can we boil this down a bit? Would a 220/240V input get me more power out of the KPA-500 (vs. a 20A 110V circuit, say)? A cleaner
signal?
Less input power consumed? Anything discernible?

~iain / N6ML

On Tue, May 3, 2011 at 7:21 PM, Clyde Washburn <[hidden email]> wrote:
> Currently the nominal voltages for most US power companies is 240/120V
> single phase, although in some areas 120/208V 3-phase is common, with
> 120V outlets being served by any one phase, and 208V circuits being
> fed across any 2 phases. Accordingly, most US appliances either have specific performance ratings that differ slightly for 208V
vs. 240V (resistive heaters and A/C compressors are a common example), or have power supply taps to accommodate either (common in
electronic equipment).
>
> The major advantage of 240V operation is improved voltage regulation:
> the same circuit, fed with the same wire (such as a common 20A 12
> gauge circuit), will have the same resistance in either case. But
> since the current is roughly half at 240V, the I*R drop will be half, which will be 1/4 the relative amount compared to the
doubled voltage. You can see that unregulated supplies will perform much better, if the current is high enough for line drop to be
noticeable.
>
> US plugs and receptacles are rated for either 125V (max) or 250V
> (max), and are non-mating between voltages, for safety. However 20A
> receptacles of ether voltage will accept 15A plugs of the same voltage, so the ideal hamshack receptacle for a linear is a
250V/20A receptacle wired to a 240V or 208V 20A circuit, which will also accept 15A 250V plugs, the smallest and most common type.

> Since 20A wiring and circuit breakers cost very little more than 15A,
> there is little point in installing 15A circuits, unless it is
> advantageous to use existing wiring in an house or building where new
> wire installation is difficult. Please note that if you convert an
> existing 120V wire run to 208 or 240V, you are obligated by code (and
> common sense) to remark the white (formerly
> neutral) wire with red paint or tape at all points of access, to
> identify as a "hot" lead. And receptacle ratings should never exceed the rating of the circuit they are on: never use a 20A
receptacle on a 15A circuit.
>
> In the specific case of the KPA500, it requires 1000VA (volt-amperes),
> so that is 8.3A at 120V, 4.8A at 208V, or 4.2A at 240V. 8.3A is not a
> particularly heavy load for a 20A circuit, but if it is a 15A circuit or is also loaded with all the other hamshack gear, then
either a separate 120V circuit for the linear, or preferably a 240V circuit is a good idea.

>
> _____________________
> Clyde Washburn, K2UE
> 82 Lasalle Pkwy
> Victor, NY 14564-9610
> 585-317-7006
> [hidden email]
>
> -----Original Message-----
> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of iain macdonnell
> - N6ML
> Sent: Tuesday, May 03, 2011 2:21 PM
> To: K2GN
> Cc: Elecraft - K3
> Subject: Re: [Elecraft] [KPA500]KPA500 power cord question
>
> On Tue, May 3, 2011 at 5:59 PM, K2GN <[hidden email]> wrote:
>> GA,
>>
>> I am in the process of rebuilding my shack and planning for the future.
>>
>> I will order a KPA500 and want to be ready for it power wise.
>>
>> I want to run it on 220V as it is available in a nearby panel.
>>
>> Question is:
>>
>> The manual states for 220V operation I would need an adaptor or new
>> plug on the power cord.
>>
>> Is this a choice that I have as far as wall outlet and matching plug?
>> If so, no problem, my electrician can fix it up.
>>
>> If it's some special, I need specs for it.
>
> I think that's left as an exercise for you ... find a heavy computer
> power cord, cut the plug off, and install one that matches your outlet .. or install a matching pair that you like.
>
> I'd be interested to hear about benefits (if any) of running the
> KPA-500 on 220V vs 110V (in the US)......
>
> ~iain / N6ML
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net Please help support this email
> list: http://www.qsl.net/donate.html
>
>

K2GN

Re: [KPA500]KPA500 power cord question

In reply to this post by Iain MacDonnell - N6ML-2

Thanks for all the replies and good info!!
de K2GN - Larry
Webmaster - http://gofrc.org
Cc: Elecraft - K3
Subject: Re: [Elecraft] [KPA500]KPA500 power cord question

On Tue, May 3, 2011 at 5:59 PM, K2GN <[hidden email]> wrote:

on
> the power cord.
>
> Is this a choice that I have as far as wall outlet and matching plug? If
so,
> no problem, my electrician can fix it up.
>
> If it's some special, I need specs for it.

______________________________________________________________
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Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:[hidden email]

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AC7AC

Re: [KPA500]KPA500 power cord question

In reply to this post by Iain MacDonnell - N6ML-2

CONTENTS DELETED

The author has deleted this message.

Iain MacDonnell - N6ML-2

Re: [KPA500]KPA500 power cord question

Right... Thanks for all the input. I think that the portability of the
KPA-500 makes sticking to 110V potentially (excuse the pun) a good
idea, unless local condx demand otherwise....

73,

~iain / N6ML

On Tue, May 3, 2011 at 8:39 PM, Ron D'Eau Claire <[hidden email]> wrote:

> No. The KPA500 peak demand is less from your 120 volt outlet than most
> household vacuum cleaners or window air conditioners. And, unless you are
> running a full-carrier mode, the average demand by your KPA500 is far below
> the peak.
>
> Of course, you want to consider all the various stuff you have plugged into
> the circuit you are using for the KPA500. It is a significant load at full
> peak power. It wouldn't be a good idea to share the same circuit with a
> window air conditioner, for example.
>
> Ron AC7AC
>
> -----Original Message-----
>
> Hi Clyde,
>
> Can we boil this down a bit? Would a 220/240V input get me more power
> out of the KPA-500 (vs. a 20A 110V circuit, say)? A cleaner signal?
> Less input power consumed? Anything discernible?
>
> ~iain / N6ML
>
>
> On Tue, May 3, 2011 at 7:21 PM, Clyde Washburn <[hidden email]>
> wrote:
>> Currently the nominal voltages for most US power companies is 240/120V
> single phase, although in some areas 120/208V 3-phase is
>> common, with 120V outlets being served by any one phase, and 208V circuits
> being fed across any 2 phases. Accordingly, most US
>> appliances either have specific performance ratings that differ slightly
> for 208V vs. 240V (resistive heaters and A/C compressors
>> are a common example), or have power supply taps to accommodate either
> (common in electronic equipment).
>>
>> The major advantage of 240V operation is improved voltage regulation: the
> same circuit, fed with the same wire (such as a common
>> 20A 12 gauge circuit), will have the same resistance in either case. But
> since the current is roughly half at 240V, the I*R drop
>> will be half, which will be 1/4 the relative amount compared to the
> doubled voltage. You can see that unregulated supplies will
>> perform much better, if the current is high enough for line drop to be
> noticeable.
>>
>> US plugs and receptacles are rated for either 125V (max) or 250V (max),
> and are non-mating between voltages, for safety. However
>> 20A receptacles of ether voltage will accept 15A plugs of the same
> voltage, so the ideal hamshack receptacle for a linear is a
>> 250V/20A receptacle wired to a 240V or 208V 20A circuit, which will also
> accept 15A 250V plugs, the smallest and most common type.
>> Since 20A wiring and circuit breakers cost very little more than 15A,
> there is little point in installing 15A circuits, unless it is
>> advantageous to use existing wiring in an house or building where new wire
> installation is difficult. Please note that if you
>> convert an existing 120V wire run to 208 or 240V, you are obligated by
> code (and common sense) to remark the white (formerly
>> neutral) wire with red paint or tape at all points of access, to identify
> as a "hot" lead. And receptacle ratings should never
>> exceed the rating of the circuit they are on: never use a 20A receptacle
> on a 15A circuit.
>>
>> In the specific case of the KPA500, it requires 1000VA (volt-amperes), so
> that is 8.3A at 120V, 4.8A at 208V, or 4.2A at 240V. 8.3A
>> is not a particularly heavy load for a 20A circuit, but if it is a 15A
> circuit or is also loaded with all the other hamshack gear,
>> then either a separate 120V circuit for the linear, or preferably a 240V
> circuit is a good idea.
>>
>> _____________________
>> Clyde Washburn, K2UE
>> 82 Lasalle Pkwy
>> Victor, NY 14564-9610
>> 585-317-7006
>> [hidden email]
>>
>> -----Original Message-----
>> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of iain macdonnell -
> N6ML
>> Sent: Tuesday, May 03, 2011 2:21 PM
>> To: K2GN
>> Cc: Elecraft - K3
>> Subject: Re: [Elecraft] [KPA500]KPA500 power cord question
>>
>> On Tue, May 3, 2011 at 5:59 PM, K2GN <[hidden email]> wrote:
>>> GA,
>>>
>>> I am in the process of rebuilding my shack and planning for the future.
>>>
>>> I will order a KPA500 and want to be ready for it power wise.
>>>
>>> I want to run it on 220V as it is available in a nearby panel.
>>>
>>> Question is:
>>>
>>> The manual states for 220V operation I would need an adaptor or new
>>> plug on the power cord.
>>>
>>> Is this a choice that I have as far as wall outlet and matching plug?
>>> If so, no problem, my electrician can fix it up.
>>>
>>> If it's some special, I need specs for it.
>>
>> I think that's left as an exercise for you ... find a heavy computer power
> cord, cut the plug off, and install one that matches your
>> outlet .. or install a matching pair that you like.
>>
>> I'd be interested to hear about benefits (if any) of running the
>> KPA-500 on 220V vs 110V (in the US)......
>>
>> ~iain / N6ML
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>
>

Joe Subich, W4TV-4

Re: [KPA500]KPA500 power cord question

In reply to this post by AC7AC

> No. The KPA500 peak demand is less from your 120 volt outlet than
> most household vacuum cleaners or window air conditioners. And,
> unless you are running a full-carrier mode, the average demand by
> your KPA500 is far below the peak.

While the average current requirement may be less that the typical
vacuum cleaner or window air conditioner, the peak current demand
*will* be significantly higher if the KPA-500 has a capacitor input
filter in the (analog) power supply.

What Ron refers to as "peak" is a long term (multi-cycle) peak
current and that is much less than the true instantaneous peak
current in a "linear" capacitor input filter power supply.
Depending on the conduction angle of the rectifier/capacitor circuit,
instantaneous peak currents use can be many times the average current
requirement - and significantly higher than the multi-cycle peak
current one would read on an amp meter in the supply line. It is
the instantaneous peak current use that drives losses in the supply
wiring and thus the effective source voltage regulation while it is
the longer term currents (and duty cycle) that impact heating.

Even with a relatively low power (average current < 10A), the peak
currents can easily exceed 50A unless the power supply includes
"power factor correction". While this will not trip breakers or
even cause heating in the wiring because of the very short duration,
with even 0.5 Ohms of resistance in the power lines, connectors, etc.
50 A peak currents can result in significant "short term" (partial
cycle) voltage drops.

Reducing the voltage drop in the supply by half is *always* a good
idea. Using 240V instead of 120V - particularly if it is already
available - is never a bad idea and certainly worth sacrificing an
inexpensive IEC cable by cutting off the 115V plug and replacing it
with the proper 240V/15A plug (often known as an "air conditioner"
plug after the old window air conditioners that required 220V/15A).

73,

... Joe, W4TV

On 5/3/2011 4:39 PM, Ron D'Eau Claire wrote:

> No. The KPA500 peak demand is less from your 120 volt outlet than most
> household vacuum cleaners or window air conditioners. And, unless you are
> running a full-carrier mode, the average demand by your KPA500 is far below
> the peak.
>
> Of course, you want to consider all the various stuff you have plugged into
> the circuit you are using for the KPA500. It is a significant load at full
> peak power. It wouldn't be a good idea to share the same circuit with a
> window air conditioner, for example.
>
> Ron AC7AC
>
> -----Original Message-----
>
> Hi Clyde,
>
> Can we boil this down a bit? Would a 220/240V input get me more power
> out of the KPA-500 (vs. a 20A 110V circuit, say)? A cleaner signal?
> Less input power consumed? Anything discernible?
>
> ~iain / N6ML
>
>
> On Tue, May 3, 2011 at 7:21 PM, Clyde Washburn<[hidden email]>
> wrote:
>> Currently the nominal voltages for most US power companies is 240/120V
> single phase, although in some areas 120/208V 3-phase is
>> common, with 120V outlets being served by any one phase, and 208V circuits
> being fed across any 2 phases. Accordingly, most US
>> appliances either have specific performance ratings that differ slightly
> for 208V vs. 240V (resistive heaters and A/C compressors
>> are a common example), or have power supply taps to accommodate either
> (common in electronic equipment).
>>
>> The major advantage of 240V operation is improved voltage regulation: the
> same circuit, fed with the same wire (such as a common
>> 20A 12 gauge circuit), will have the same resistance in either case. But
> since the current is roughly half at 240V, the I*R drop
>> will be half, which will be 1/4 the relative amount compared to the
> doubled voltage. You can see that unregulated supplies will
>> perform much better, if the current is high enough for line drop to be
> noticeable.
>>
>> US plugs and receptacles are rated for either 125V (max) or 250V (max),
> and are non-mating between voltages, for safety. However
>> 20A receptacles of ether voltage will accept 15A plugs of the same
> voltage, so the ideal hamshack receptacle for a linear is a
>> 250V/20A receptacle wired to a 240V or 208V 20A circuit, which will also
> accept 15A 250V plugs, the smallest and most common type.
>> Since 20A wiring and circuit breakers cost very little more than 15A,
> there is little point in installing 15A circuits, unless it is
>> advantageous to use existing wiring in an house or building where new wire
> installation is difficult. Please note that if you
>> convert an existing 120V wire run to 208 or 240V, you are obligated by
> code (and common sense) to remark the white (formerly
>> neutral) wire with red paint or tape at all points of access, to identify
> as a "hot" lead. And receptacle ratings should never
>> exceed the rating of the circuit they are on: never use a 20A receptacle
> on a 15A circuit.
>>
>> In the specific case of the KPA500, it requires 1000VA (volt-amperes), so
> that is 8.3A at 120V, 4.8A at 208V, or 4.2A at 240V. 8.3A
>> is not a particularly heavy load for a 20A circuit, but if it is a 15A
> circuit or is also loaded with all the other hamshack gear,
>> then either a separate 120V circuit for the linear, or preferably a 240V
> circuit is a good idea.
>>
>> _____________________
>> Clyde Washburn, K2UE
>> 82 Lasalle Pkwy
>> Victor, NY 14564-9610
>> 585-317-7006
>> [hidden email]
>>
>> -----Original Message-----
>> From: [hidden email]
> [mailto:[hidden email]] On Behalf Of iain macdonnell -
> N6ML
>> Sent: Tuesday, May 03, 2011 2:21 PM
>> To: K2GN
>> Cc: Elecraft - K3
>> Subject: Re: [Elecraft] [KPA500]KPA500 power cord question
>>
>> On Tue, May 3, 2011 at 5:59 PM, K2GN<[hidden email]> wrote:
>>> GA,
>>>
>>> I am in the process of rebuilding my shack and planning for the future.
>>>
>>> I will order a KPA500 and want to be ready for it power wise.
>>>
>>> I want to run it on 220V as it is available in a nearby panel.
>>>
>>> Question is:
>>>
>>> The manual states for 220V operation I would need an adaptor or new
>>> plug on the power cord.
>>>
>>> Is this a choice that I have as far as wall outlet and matching plug?
>>> If so, no problem, my electrician can fix it up.
>>>
>>> If it's some special, I need specs for it.
>>
>> I think that's left as an exercise for you ... find a heavy computer power
> cord, cut the plug off, and install one that matches your
>> outlet .. or install a matching pair that you like.
>>
>> I'd be interested to hear about benefits (if any) of running the
>> KPA-500 on 220V vs 110V (in the US)......
>>
>> ~iain / N6ML
>> ______________________________________________________________
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>>
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Phil Salas

Re: [KPA500]KPA500 power cord question

In reply to this post by K2GN

I run my KPA500 on 240VAC. I purchased a C13615P-6 power cord from
www.cables.com ($12.00 plus $6.45 shipping) which matches the NEMA 6-15
240VAC outlet receptacle in my shack. Plug-N-Play. This just replaces the
120VAC cord that came with the KPA500.

Phil - AD5X

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Dick Dievendorff

Re: [KPA500]KPA500 power cord question

I bought mine from Phil's source after reading his earlier note.

I'm planning to wire my new shack with a couple of NEMA 6-15/20R receptacles
and the corresponding 20A circuits.

The 20A circuits are sufficient for legal limit amplifiers, and the cost
difference between 15 and 20A capacity is often minor. 20A is a very common
circuit capacity.

The NEMA 6-15/20R receptacle accepts either NEMA 6-15P or 6-20P plugs.

73 de Dick, K6KR

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of Phil & Debbie Salas
Sent: Tuesday, May 03, 2011 3:24 PM
To: [hidden email]
Subject: Re: [Elecraft] [KPA500]KPA500 power cord question

I run my KPA500 on 240VAC. I purchased a C13615P-6 power cord from
www.cables.com ($12.00 plus $6.45 shipping) which matches the NEMA 6-15
240VAC outlet receptacle in my shack. Plug-N-Play. This just replaces the
120VAC cord that came with the KPA500.

Phil - AD5X

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Jim Brown-10

Re: [KPA500]KPA500 power cord question

In reply to this post by Iain MacDonnell - N6ML-2

On 5/3/2011 11:20 AM, iain macdonnell - N6ML wrote:
> I'd be interested to hear about benefits (if any) of running the
> KPA-500 on 220V vs 110V (in the US)

The only good reason I can think of is if the 120V circuit that runs
your ham shack would be overloaded by adding the amp. That's a rather
unlikely scenario. A single 15A circuit is good for 1,800 watts. The
KPA500 specs say it needs 1,000 VA, which is 8.3A. That leaves 6.7A
(800W) to run the rest of your ham gear. Because most power amps,
including the KPA500, get to full power with less than 50 watts, you'll
only need about 2A at 120V for the transceiver. Even with SO2R, you're
only transmitting with one radio at a time, and transceivers don't burn
my power in RX mode (especially Elecraft radios).

The one good reason for having 240V in your shack if if you think you
might want to run an amp rated at 1kW or higher, or if you might need a
space heater.

If I were pulling new wiring into a ham shack, I would install one 20A
120V circuit and one 20A 240V circuit for ham gear (and computer gear)
only. I would put LOTS of outlets on the 120V circuit, and I would put
them in steel backboxes that are all bonded together, and to the backbox
for the 240V outlet.

If I thought the station might someday want to do multi-two contesting,
I would double up both circuits, but I would still keep them all bonded
together.

73, Jim K9YC

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Jim Brown-10

Re: [KPA500]KPA500 power cord question

In reply to this post by Iain MacDonnell - N6ML-2

On 5/3/2011 12:43 PM, iain macdonnell - N6ML wrote:
> Anything discernible?
>

NO!

Jim

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AC7AC

Re: [KPA500]KPA500 power cord question

In reply to this post by Joe Subich, W4TV-4

CONTENTS DELETED

The author has deleted this message.

Don Wilhelm-4

Re: [KPA500]KPA500 power cord question

In reply to this post by K2GN

Larry,

You should look at it from a slightly different perspective. If the
current load on your 120 volt AC receptacle is large, then you would
need to consider additional current for the KPA500.
I might also add that if one is considering additional wiring to the
hamshack location to provide power for the KPA500, then (and only then)
would a 240 volt run be desirable.

The KPA500 will run nicely on a 120 volt AC receptacle, so only in the
case where the existing 120 volt receptacles are maxed out in the
hamshack would I consider running a separate 240 volt line to power the
KPA500.

In other words, it all depends on what you have for AC power in the
hamshack right now.
I have a dedicated 120 volt 20 amp circuit to my hamshack location, and
I do not intend to run a separate 240 volt line for any amplifier unless
it becomes absolutely necessary.

73,
Don W3FPR

On 5/3/2011 1:59 PM, K2GN wrote:

> GA,
>
> I am in the process of rebuilding my shack and planning for the future.
>
> I will order a KPA500 and want to be ready for it power wise.
>
> I want to run it on 220V as it is available in a nearby panel.
>
> Question is:
>
> The manual states for 220V operation I would need an adaptor or new plug on
> the power cord.
>
> Is this a choice that I have as far as wall outlet and matching plug? If so,
> no problem, my electrician can fix it up.
>
> If it's some special, I need specs for it.
>
> Thank you in advance,
>
> de K2GN - Larry<mailto:[hidden email]> - http://k2gn.com<http://k2gn.com/>
>
>
> K3 S/N - 3278 P3 S/N - 51
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

MontyS

Re: [KPA500]KPA500 power cord question

In reply to this post by AC7AC

I have been using an ALS-600, the 600-watt Ameritron solid state amp, for two years. My shack is wired for 120 volts, 20 amps, 2 circuits.

The voltage from the power supply drops only slightly when transmitting, almost surely from internal factors, not house wiring. The AC mains voltage does not drop.

I have never tripped a breaker.

The Elecraft Amp is probably more power efficient than the ALS-600 with its sophisticated power supply. I'd worry about something else.

FWIW.

Monty K2DLJ

> The important point is whether the voltage to the finals at full output is
> as different when the KPA500 is supplied by 240 or 120V mains. I believe the
> answer is "no". AFAIK, the KPA500, and it's power supply, was designed and
> tested to meet all of its performance specifications with either a 120V or
> 240V mains supply. - Ron D'Eau Claire
>
>
>
>> No. The KPA500 peak demand is less from your 120 volt outlet than
>> most household vacuum cleaners or window air conditioners. And,
>> unless you are running a full-carrier mode, the average demand by
>> your KPA500 is far below the peak. - Joe Subich

Re: [KPA500]KPA500 power cord question

If you have a dedicated 120V circuit for your ham shack and only run one
transceiver and one medium power amp you will probably be OK. The trouble comes
from using a house circuit that already has other users and was designed for
those users. Many house circuits use #14 wire and are good for 15 amps max.
You may already have the lights in the room and a few clocks and other things.
Add on a TV set and your wife's hair dryer and you are in trouble, so you need
to do a load analysis. If you are going to run another circuit, it might as
well be 220, or run two more circuits, a 110 and a 220. But, you are never safe
to just plug in several medium to high current loads without doing at least an
informal load analysis. If you have too many loads on a circuit you will soon
lose your claim to "Never popping a breaker".
Willis 'Cookie' Cooke
K5EWJ

________________________________
From: Monty Shultes <[hidden email]>
To: Ron D'Eau Claire <[hidden email]>
Cc: "[hidden email]" <[hidden email]>
Sent: Wed, May 4, 2011 5:49:25 AM
Subject: Re: [Elecraft] [KPA500]KPA500 power cord question

I have been using an ALS-600, the 600-watt Ameritron solid state amp, for two
years. My shack is wired for 120 volts, 20 amps, 2 circuits.

The voltage from the power supply drops only slightly when transmitting, almost
surely from internal factors, not house wiring. The AC mains voltage does not
drop.

I have never tripped a breaker.

The Elecraft Amp is probably more power efficient than the ALS-600 with its
sophisticated power supply. I'd worry about something else.

FWIW.

Monty K2DLJ

Edward R Cole

Re: [KPA500]KPA500 power cord question

In reply to this post by K2GN

I ran a Swan Mark-III (2x3-400z) PS on 120vac in a bedroom (My ham
shack) running 2500vdc @ 400mA (1000VA) to run my 2m-8877 to 600w
output. That PS drew at least as much as the KPA500 will. I only
saw a slight momentary flicker in the room lights when I switched to
transmit (I am transmitting key-down for one minute using digital modes).

I only ran 240vac when I upgraded to a 4kV@1amp HVPS. I ran 35-foot
of #8-4 wiring to a small breaker box with one 20A 240v breaker and
two 20A 120v breakers. That provided some separate circuits for my
low-voltage PS so that the rest of the ham shack could run on the
house circuits. Now I am adding a 3500VA 50vdc PS for 6m-QRO, so
will have to add another 240v outlet. I will not add any breakers
since I will not run both 6m-QRO and 2m-QRO at the same time.

The HP switching PS (50v@50A) only cost me $18 on e-bay! It will
supply a Harris Platinum 1100w SSPA (16 LDMOS transistors) that is a
pull from a chan-2 TV station. They were used as drivers for 50kW
transmitters!

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

Message: 1
Date: Tue, 03 May 2011 19:32:33 -0700
From: Jim Brown <[hidden email]>
Subject: Re: [Elecraft] [KPA500]KPA500 power cord question
To: [hidden email]
Message-ID: <[hidden email]>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

On 5/3/2011 11:20 AM, iain macdonnell - N6ML wrote:
> I'd be interested to hear about benefits (if any) of running the
> KPA-500 on 220V vs 110V (in the US)

The only good reason I can think of is if the 120V circuit that runs
your ham shack would be overloaded by adding the amp. That's a rather
unlikely scenario. A single 15A circuit is good for 1,800 watts. The
KPA500 specs say it needs 1,000 VA, which is 8.3A. That leaves 6.7A
(800W) to run the rest of your ham gear. Because most power amps,
including the KPA500, get to full power with less than 50 watts, you'll
only need about 2A at 120V for the transceiver. Even with SO2R, you're
only transmitting with one radio at a time, and transceivers don't burn
my power in RX mode (especially Elecraft radios).

The one good reason for having 240V in your shack if if you think you
might want to run an amp rated at 1kW or higher, or if you might need a
space heater.

If I were pulling new wiring into a ham shack, I would install one 20A
120V circuit and one 20A 240V circuit for ham gear (and computer gear)
only. I would put LOTS of outlets on the 120V circuit, and I would put
them in steel backboxes that are all bonded together, and to the backbox
for the 240V outlet.

If I thought the station might someday want to do multi-two contesting,
I would double up both circuits, but I would still keep them all bonded
together.

73, Jim K9YC

73, Ed - KL7UW, WD2XSH/45
======================================
BP40IQ 500 KHz - 10-GHz www.kl7uw.com
EME: 50-1.1kW?, 144-1.4kw, 432-100w, 1296-testing*, 3400-?
DUBUS Magazine USA Rep [hidden email]
======================================
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Fred Townsend

Re: [KPA500]KPA500 power cord question

In reply to this post by Cookie

I will add a few comments to Cookie's good advice. If you are wondering if
your ham shack is wired with 15 or 20 amp service here is an easy way to
tell. There are two common types of grounded duplex receptacles available in
the USA. The NEMA 5-15R type has two parallel blades with the U ground pin
on top and the right hand neutral blade is somewhat larger. This receptacle
is rated for 15 amps and is normally wired with 14 gage wire. The NEMA 5-20R
receptacle looks much the same except the right hand blade is T shaped (the
T is laying down) and should be wired with 12 gage wire. NEMA 5-20R plugs
are usually listed as 'Industrial' and therefore not necessarily found in
the same electrical section of Home Depot.

If you are installing a new circuit 240 VAC is preferable. The current is
less and therefore the copper losses lower and everything, including your
power supply, runs cooler.
de Fred, AE6QL

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of WILLIS COOKE
Sent: Wednesday, May 04, 2011 5:29 AM
To: Monty Shultes; Ron D'Eau Claire
Cc: [hidden email]
Subject: Re: [Elecraft] [KPA500]KPA500 power cord question

If you have a dedicated 120V circuit for your ham shack and only run one
transceiver and one medium power amp you will probably be OK. The trouble
comes from using a house circuit that already has other users and was
designed for those users. Many house circuits use #14 wire and are good for
15 amps max. You may already have the lights in the room and a few clocks
and other things. Add on a TV set and your wife's hair dryer and you are in
trouble, so you need to do a load analysis. If you are going to run another
circuit, it might as well be 220, or run two more circuits, a 110 and a
220. But, you are never safe to just plug in several medium to high current
loads without doing at least an informal load analysis. If you have too
many loads on a circuit you will soon lose your claim to "Never popping a
breaker".
Willis 'Cookie' Cooke
K5EWJ

________________________________
From: Monty Shultes <[hidden email]>
To: Ron D'Eau Claire <[hidden email]>
Cc: "[hidden email]" <[hidden email]>
Sent: Wed, May 4, 2011 5:49:25 AM
Subject: Re: [Elecraft] [KPA500]KPA500 power cord question

I have been using an ALS-600, the 600-watt Ameritron solid state amp, for
two years. My shack is wired for 120 volts, 20 amps, 2 circuits.

The voltage from the power supply drops only slightly when transmitting,
almost surely from internal factors, not house wiring. The AC mains voltage
does not drop.

I have never tripped a breaker.

The Elecraft Amp is probably more power efficient than the ALS-600 with its
sophisticated power supply. I'd worry about something else.

FWIW.

Monty K2DLJ

> The important point is whether the voltage to the finals at full
> output is as different when the KPA500 is supplied by 240 or 120V
> mains. I believe the answer is "no". AFAIK, the KPA500, and it's power
> supply, was designed and tested to meet all of its performance
> specifications with either a 120V or 240V mains supply. - Ron D'Eau
> Claire
>
>
>
>> No. The KPA500 peak demand is less from your 120 volt outlet than
>> most household vacuum cleaners or window air conditioners. And,
>> unless you are running a full-carrier mode, the average demand by
>> your KPA500 is far below the peak. - Joe Subich

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K2GN

Re: [KPA500]KPA500 power cord question

Gentlemen:
I appreciate all the input, but the question has been answered.
To clarify, this is a modification, reconfiguration of an existing shack.
There's power there, 115V and 220V. There's an opportunity for a 2nd 220V
line.
I'm going to do that, I needed to know what type of power cord was needed.
Now I got that and it's ordered.
Thank you all for your input.
de K2GN - Larry - http://k2gn.com
K3 S/N - 3278 P3 S/N - 51

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