Richard wrote:
> >
> >
> >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
The ground and neutral wires are connected together in the breaker box. But
you
don't always know about how things are between the outlet and the breaker
box.
The whole idea of course is for the ground/green wire to never carry any
current.
It is there only as a safety device.
The only exception to that rule that I can recall is the wiring of an
electric
stove. There only 3 wires are run. 2 hot and a ground wire. No neutral but
they do
run current in the ground wire for any 120 volt items on the stove. Timer,
120 volt
outlet etc. HOWEVER the line for the stove must be a dedicated line
directly from
the stove to the breaker panel where of course the neutral and ground are
tied
together. (I think that someone posted that the codes have changed and now
newer
wiring requires 4 wires)
When you don't have a direct line, ie, there are other outlets connected on
the
same branch circuit there is the possibility for some other outlets ground
circuit
to be elevated above ground if you are running current on the ground wire
rather
than a neutral wire. This is particularly important if there is a poor
connection
somewhere along the way.
So any time that your 220volt amp has any current requirements at 120 volts
you
need to have a 4 wire line to be legal and safe.
73
Gary K4FMX
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