I have yet to see a commercially built 120/240 VAC Ham amplifier with a step
down transformer to run the 120 VAC fan and probably the filament
transformer as well...
Some may exist, but I have yet to encounter one. Not to say that wouldn't be
good engineering practice, but then there is the real world. I have seen
some commercial single phase Broadcast equipment where it wasn't done
either. Looks like lots of manufactors have gone astray! You can pretty
much run down the list of the Ham Amp builders, and they are all guilty!!!
Anyway I believe the rule is it is OK to Ground the Neutral, but NOT OK to
tie the Neutral the Ground..Unless your are the Power Company, then guess
what they do to the Neutral at the entrance to your house and all along the
system. ...According to the NEC code as adopted in 1996 it is OK and
considered safe, when necessary, to supply both 120 and 240 volt loads in an
appliance that uses a 3 wire 220/240 VAC cord! My statement was not
intended to say that ground and neutral are the same, what I said was in
that case they were the same, meaning the only neutral available is the
ground wire. Your staement, that it is NEVER, EVER, ACCEPTABLE to operate a
110/120 volt load between 120 line and ground is simply inaccurate, keeping
in mind that I am talking about when the load is contained within an
appliance that has a primary source from a 3 wire 220/240 VAC cord! If it
were not, there would be thousands of electric clothes dryers in this
country operating improperly.And yes I know the new ones come with 4 wire
cords.But there are still thousands and thousands of the 3 wire ones out
there. And then there are probably some 220 volt Air Conditioners...and what
else might we find???
W6RD
----- Original Message -----
From: "Ken Brown" <ken.d.brown@hawaiiantel.net>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Friday, January 04, 2008 8:37 PM
Subject: Re: [TenTec] Centaur Power Cord
Hi Mike,
The convention is that blue in a blue/green/brown cord corresponds to
white in white/green/black cord. And brown corresponds to black. Green
or green with a yellow stripe is ground. In a three wire 220 power cord
there is no neutral. There are two hot leads and a ground. NEUTRAL IS
NOT THE SAME AS GROUND, anywhere except in the main load center panel
(meter panel or circuit breaker panel) where they are connected. Three
wire 220 circuits cannot have any 110 loads from one hot lead to
neutral, since there is not neutral wire, and no load of any kind should
ever be connected between a hot lead and ground. If a piece of equipment
fed by a three wire 220 circuit has a fan or other small 110 volt load
inside it, that load must be fed by a 220/110 stepdown transformer. A
four wire 220/110 circuit can supply both 220V and 110V, since it does
have a neutral AND a ground, which are two separate wires.
Again, just to be clear: NEUTRAL IS NOT THE SAME AS GROUND!!!
Make sure you understand this before you attempt any connection to any
AC power source of any voltage.
I'm sure you will get plenty of responses to this ground = neutral error
on the reflector. No doubt one of them will explain why GROUND IS NOT
THE SAME AS NEUTRAL. I'll explain it later if nobody else does.
DE N6KB
I just bought a used Centaur and want to change from 110v to 220v
source.
Have reconfigured jumpers for 220v but don't understand the color code
to
install 220 plug on power cord. Changing from AL811H which uses
standard
"black/white/green" color coding, Centaur has "blue/green/brown" wiring
color code.
Can anyone enlighten me on which color is neutral, etc ? Thanks for
the
help, 73. Mike K4KJC
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