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Wayne Cook
 
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On Thu, 28 Jul 2005 18:54:13 GMT, Ignoramus9394
wrote:

On Thu, 28 Jul 2005 18:40:45 GMT, Jerry Martes wrote:

As I remember instructions, the contactor does drop out when the 240
single phase power is lost. That assumes that you use buttons to engage
the idler.


Jerry, I am a little confused, what particular contactor are you
talking about? My definite purpose furnas contactor? If so, I believe
(and will verify it tonight) that it is stupid and closes when 110V is
applied to the coil, that's all.


This just means that you've wired it to a standard switch. Normally
for motor use the contactor is switched with two push button switches.
One is normally open and the other is normally closed. The normally
closed switch is wired to the output of the contactor in such a way
that when the contactor is closed it provides itself the coil voltage.
When the normally closed switch is pressed this breaks the coil
voltage allowing it to shut off. The normally open switch is wired to
the input line and then to the coil. This allows pressing that button
to start the coil which is then held by the above switch.

The problem here is that IIRC you've got a 120v coil on your
contactor. This makes it difficult to wire this type of switch up. The
only way I can think of right now would require two transformer to
bring the 220v down to 120v.