A common workaround is to cover the white wire end with black tape or heat
shrink. This was allowed in the NEC book 25 years ago; not sure about today.
The use of four wires can be a problem if the existing 240vac outlet has
only three wires. If three wires worked when the amplifier was manufactured why
can't they work today? If rewiring the amplifier and cord for 240vac cuts the
primary current in half then the power loss is cut into one fourth. What is
wrong with that?
73/k5gw
In a message dated 10/2/2005 4:11:56 P.M. Central Standard Time,
craxd1@verizon.net writes:
Bill,
I can tell you that the NEC sure does frown on using white as a hot. There's
only one permissible way they allow it and that is for the switch leg on a
wall controlling an overhead lamp. There you run the hot to the white of the
switch and bring it's black back to the black of the lamp. Using white for a
hot in a power cord is the same as using the green as laid out by the NEC.
Most pigtails have no color code like the grey ones but mark the outside with
some ridges for the neutral. Then when using them your supposed to ad an
external ground wire from the chassis to ground. That's not the way I spell it
out
but the way the NEC does. The wire don't know what color it is, but when
someone mistakes a white for a hot, it could cause harm if they didn't know it
was tied to hot.
Best,
Will
*********** REPLY SEPARATOR ***********
On 10/2/05 at 4:53 PM Bill Coleman N2BC wrote:
>It is quite OK to use the white on one of the phases in a 240V hookup.
>It
>is never OK to use green to anything other than ground.
>
>Most modern amps have no need for neutral when wired for 240V. If neutral
>is indeed needed for something inside that is 120V only then the only way
>is
>to use a 4-wire cord.
>
>Bill N2BC
>----- Original Message -----
>From: "Will Matney" <craxd1@verizon.net>
>To: <amps@contesting.com>
>Sent: Sunday, October 02, 2005 3:58 PM
>Subject: Re: [Amps] Power cord to use when converting AL-80B to 240 volts?
>
>
>> Colin,
>>
>> That's true as long as the cable is rated for 220 Vac, and you don't
>want
>> to add a ground with the neutral. To do it right, I'd want a three wire
>> with ground cord. Most 120 Vac cords only have three wires. To use a 120
>> Vac cord on 220, you'd have to use the ground wire for the neutral which
>> most of the time is a green wire. That is if you intend on using
>anything
>> on the 120 Vac line. Plus your using a white wire as a hot. The correct
>> way is have a black and red wire as hot, white as the neutral, and green
>> to ground.
>>
>> Best,
>>
>> Will
>>
>> *********** REPLY SEPARATOR ***********
>>
>> On 10/2/05 at 12:47 PM k7fm wrote:
>>
>>>If the mains cable for the amp is designed for 120 volts, it will handle
>>>240
>>>volts. The current is 1/2 at 240 volts, so you could actually make the
>>>cable smaller.
>>>
>>>Regarding voltage rating, each wire is 120 volts to ground, so the
>>>insulation need be no higher than for 120 volts (insulation between wires
>>>is
>>>doubled because both wires are insulated.
>>>
>>>Colin K7FM
>>>
>>>_______________________________________________
>>>Amps mailing list
>>>Amps@contesting.com
>>>http://lists.contesting.com/mailman/listinfo/amps
>>
>>
>>
>> _______________________________________________
>> Amps mailing list
>> Amps@contesting.com
>> http://lists.contesting.com/mailman/listinfo/amps
>>
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|