Yes Bill, a simple rule is "ground should never carry any current".
One note about ground fault breakers, if you are gong to install them on a 220
volt line they need to be double pole type just like any other 220 breaker. They
are kind of hard to find I think.
73
Gary K4FMX
Bill Coleman wrote:
> Ground and Neutral are the same in the MAIN breaker box - not necessarily in
> all breaker boxes... A branch circuit (probably quite common for
> post-construction install of 240V in our shacks) must have the neutral and
> ground separated. You should not wire up a device anywhere which requires
> neutral (i.e. the neutral is carrying current) to the ground instead of
> neutral.
>
> A slight digression: Ground-fault and arc-fault breakers rely on separate
> ground and neutral - or stated differently, they rely on current NOT being
> returned on the ground. I would recommend that our shack and workshop
> branch circuits all be fed by a ground-fault breaker. I feel better knowing
> that a milliamp difference in the load between hot and neutral will likely
> trip the breaker rather than a 40A overload running up my arm and out to the
> frame of a piece of radio junque.
> ~~~~~~~~~~~~~~~~
> Bill Coleman N2BC
> http://home.stny.rr.com/n2bc
> ----- Original Message -----
> From: "Richard" <2@mail.vcnet.com>
> To: "Gary Schafer" <garyschafer@attbi.com>
> Cc: "Steve Katz" <stevek@jmr.com>; <RMead100@aol.com>; "AMPS"
> <amps@contesting.com>
> Sent: Friday, March 08, 2002 7:02 AM
> Subject: Re: [Amps] Source for 220V cords
>
> >
> >
> >Richard wrote:
> >
> >> >A window air conditioner cord is what you want. They have a molded plug
> on
> >> >them,
> >> >although they are not usually all that long. Can be found in Home Depot,
> >> >Lows or
> >> >probably most larger hardware stores.
> >> >
> >> >By the way I think that a 15 amp 220 plug has one blade turned 90
> degrees
> >and
> >> >the 20 amp plug has both blades 90 degrees from what a standard 120 volt
> >plug
> >> >would be.
> >> >These are all 3 wire plugs. 2 hot and ground. No neutral connection. I
> think
> >> >that the SB220 will run without the neutral on 220 vac.
> >> >
> >> Do this and the chassis is not returned to mains neutral/gnd at the
> >> breaker box.
> >>
> >> - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
> >> www.vcnet.com/measures.
> >> end
> >
> >I am not sure about the SB220 but the SB200 does not require a neutral
> connection
> >on 220 volts. The fan is the only 120 volt item in the amp. It gets
> connected
> from
> >one hot side to the center connection of the transformer primary. This acts
> as an
> >auto transformer to give 120 volts for the fan.
>
> ? True. Gary. Also, green/ground and white/neutral are the same point
> in the breaker box.
>
> >The chassis ground still goes to
> >the green wire (center pin) as it did with the 120 volt connection. No
> neutral
> >connection is needed as there is no 120 volts as far as the line is
> >concerned.
>
> - R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
> www.vcnet.com/measures.
> end
>
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