>OK Rich,
>
>The green I was referring to was the green labeled wire on the schematic for
>the SB-220. This wire is connected to the ground terminal of the plug in the
>schematic.
>
** I concur.
>You are saying that your outlet's neutral wire "connects back to the 240v
>neutral (the C.T.) terminal in the breaker box", Here the color does
matter, if you care
>about the electrical code. This wire must be bare copper or green or some
>other color "tagged" with green tape.
** As I recall, the wire is 12-gauge bare Cu. It is embedded at the
center of 12-3 blk/wht color-coded romex. According to the latest code,
this cable should probably be red/black/wht/grn 12-4. Also, the
20A,240V, 3-prong outlet should probably be changed to a 4-pronger and
the 20A circuit breaker should probably be changed to a GFI-type.
>I could be wrong about "tagging" a
>non-green wire.
** This makes sense to me. I would be in favor of using grey wire
everywhere and applying touch-up paint of the correct color. A serious
problem with my 50A, 240v outlet is that all three wires are black. Next
time I'm in K-Mart, I'll see whats available in the Cosmetics department.
(I like the idea of having a brush in the cap.). What do you think
about painting the black #6 neutral/ground wire green & white striped
plus paint one black #4 hot wire red.
>
>More importantly - and the real point here... is that the bare or green wire
>is not neutral. In today's code, the neutral and the ground are two separate
>conductors. While they are indeed connected together in the service
>entrance panel, they are two separate conductors once they leave the panel.
>
>Neutral carries current - the 'return' for 120V circuits. The safety ground
>never carries current unless there is a fault.
>
>The SB-220/221 diagram that I have correctly shows a safety ground to the
>chassis (labelled green) for both 120V and 240V setups. When wired for 240V
>the SB-221/221 uses both "hot" sides of the AC circuit with no connection to
>neutral. When wired for 120V the SB-220/221 uses one "hot" side and neutral.
>I am carefully avoiding using color references.
>
>Your installation:
>
>> I Have a 3-wire 240v outlet in the radio-room. The
>> Neutral wire on this outlet connects back to the 240v neutral (the C.T.)
>> terminal in the breaker box.- which is also the ground terminal in the
>> breaker box.
>
>If the wire you call "neutral" is connected to safety ground only, then it
>is probably wired correctly for 240V only device. I would call that wire
>safety ground, I would make sure that wire was bare or green.
>
>If the wire you call "neutral" in your outlet connects to neutral anywhere
>outside of the service entrance breaker box, then it is indeed a neutral and
>not a safety ground. This would not be proper wiring for a 3-wire 240V
>outlet.
** It is not proper/legal to scissor-off fabric labeling tags that poke
one in the neck and posterior, but I do. It isn't considered proper by
some amplifier experts to modify a commercial amplifier's circuitry ...
... ... .
>
>I am being careful to specify service entrance breaker box. This is the only
>place that safety ground and neutral are connected together. If there is a
>downstream branch circuit box, the safety ground is bonded physically to the
>box and the neutrals are isolated on their own bus above ground.
>
>On the subject of colors... they are important, but all too often ignored.
** That's what my wife and the neighbor girl that does mail-orders keep
telling me.
>The electrical code spells out acceptable colors and standards for marking
>conductors correctly. Unfortunately they are ignored or misused or
>misinterpreted. I personally never trust someone else's wiring, that can
>get you killed.
** Amen to that - which is why I use a DMM to find out what's really the
R of a "50-ohm" dummy load and also what's what with an electrical outlet
I did not wire. I know of a professionally-installed 240v, 20a outlet
in Van Nuys that had 240v between N. and L-1, which smoked a 30L-1, and
damn near smoked the operator. (W6AG)
>
>On that note, this subject is truly beat to death.
** So let's light the barbee and open some Fosters, Bill.
>
>
>----- Original Message -----
>From: "R.Measures" <r@somis.org>
>To: "Bill Coleman" <n2bc@stny.rr.com>; <Ku4uk@aol.com>; "AMPS"
><amps@contesting.com>
>Sent: Sunday, December 07, 2003 1:18 AM
>Subject: Re: [Amps] RE 220 V
>
>
>>
>>
>> >Sorry Rich, you are not correct. The voltage is irrelevant. Neutral
>> >carries current, ground never carries current unless there is a fault.
>The
>> >diagram of the SB220/221 plug that I have clearly shows the green wire to
>> >ground in the plug for both 120V and 240V setups.
>> Bill --
>> ** What I am telling you is that green is not a sacred color to this
>> radio operator. I Have a 3-wire 240v outlet in the radio-room. The
>> Neutral wire on this outlet connects back to the 240v neutral (the C.T.)
>> terminal in the breaker box.- which is also the ground terminal in the
>> breaker box. If I had not connected the green wire in the SB220's
>> 3-wire cord to 240v neutral, I would not have a ground return on the
>> SB-220's chassis. - - How would you have wired the 240V 3-wire plug?
>> >
>> >Bill N2BC
>> >
>> >
>> >----- Original Message -----
>> >From: "R. Measures" <r@somis.org>
>> >To: "Bill Coleman" <n2bc@stny.rr.com>; <Ku4uk@aol.com>; "AMPS"
>> ><amps@contesting.com>
>> >Sent: Saturday, December 06, 2003 5:01 PM
>> >Subject: Re: [Amps] RE 220 V
>> >
>> >
>> >>
>> >>
>> >> >NOT TRUE.
>> >>
>> >> ** It's true on my SB-220. When wired for 240V, the third wire
>(green)
>> >> goes to the neutral on the 240v 3-conductor plug and the other end of
>> >> this wire goes to chassis. On a 3-conductor 240v circuit, the ground
>is
>> >> the neutral. 0v = 0v.
>> >> >
>> >> >There may be older vintages of the SB-220. But I looked at an undated
>> >> >SB-220 schematic and an SB-221 schematic dated 1976. Both of these
>> >clearly
>> >> >show GROUND to the chassis - the wire is labelled GREEN and the
>> >picto-gram
>> >> >of the plug clearly shows it connected to the ground lug. When wired
>for
>> >> >240V, there is no need for a neutral on an SB-220/221.
>> >> >
>> >> >If in fact early SB-220s wired neutral to the chassis, they should be
>> >> >changed. Just because they did it at one time doesn't make it correct
>> >> >today. The Collins KWS-1 shipped with neutral to the chassis and they
>> >> >should all be changed. Lots of Johnson and Heath gear shipped with
>those
>> >> >deadly fuse plugs - they should be changed!
>> >> >
>> >> >We need to move on.
>> >> >
>> >> >
>> >> >----- Original Message -----
>> >> >From: "R.Measures" <r@somis.org>
>> >> >To: <Ku4uk@aol.com>; "AMPS" <amps@contesting.com>
>> >> >Sent: Friday, December 05, 2003 9:25 PM
>> >> >Subject: Re: [Amps] RE 220 V
>> >> >
>> >> >
>> >> >>
>> >> >>
>> >> >> >No one has said anything about the heathkit SB 22O wiring. It has
>two
>> >hot
>> >> >> >wires to transformer and neutral to chassis
>> >> >>
>> >> >> Neutral does not go to the chassis when a 220 is wired for 120V, but
>> >> >> wired for 240v it does
>> >> >>
>> >> >> >....
>> >> >> _______________________________________________
>> >> >> Amps mailing list
>> >> >> Amps@contesting.com
>> >> >> http://lists.contesting.com/mailman/listinfo/amps
>> >> >>
>> >> >
>> >> >
>> >> >
>> >>
>> >
>> >
>> >
>> _______________________________________________
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>>
>
>
>
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