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Switching a neutral

Switching a neutral

Switching a neutral

(OP)
Customer has a DPST , Normally open relay (30 amp). They want this to turn a pump on and off.  (Act as a contactor) The coil voltage is 24 VAC which is controled by a separate source.  The pump motor could be 115 or 220 volts. At 220 volts no problem, switch both legs to start/stop the pump.

At 115 volts do you switch the hot and the neutral ? My tired brain tells me there is something in the codes not allowing you to the switch the neutral. But I haven't found it yet.

Thanks in advance for the help

 

RE: Switching a neutral

You can switch them both.
You don't want to switch the ground.

Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com

RE: Switching a neutral

You don't have to switch the neutral except in a few very specific instances but there is no prohibition against switching the neutral as long as the neutral is only switched with the phase conductor(s).

RE: Switching a neutral

The line and neutral must switch simultaneously, or the line may be an early break, late make. Under no circumstances may the neutral be open when the line is closed (connected).
A two pole manual or magnetic motor starter is generally accepted as conforming to the simultaneous make and break requirement.

Bill
--------------------
"Why not the best?"
Jimmy Carter

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