GFCI 120 vs 220 Pool Timer

tgmccallieSeptember 4, 2012

I am replacing a 220 volt Intermatic pool timer with a new one where the timer motor will work on 120 or 240 volts.

The other loads are dry loads that will handle either voltage.

I have 240 volts line going to sub panel which has a black, red, and ground wire (no neutral). This is the same wire that I had hooked to my 240 volt timer that I am replacing.

Problem is: I want to wire the new timer up as follows....

Wire timer 120 volts and the pump and cleaner as 240.

I did this by installing 2 double pole breakers for the pump and cleaner and a single pole 120 volt breaker for the timer.

The problem is the GFCI trips when I turn on the power to the 120 volt timer. Is that because there is no neutral wire for the line?

If I change this and wire the timer as 240 on a double pole 240 breker will that cure the problem?


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Ron Natalie

Which GFCI trips? Are you we talking about a GFCI feeding a sub panel?
Yes if there is no load neutral on that GFCI, connecting one of the protected legs rightfully gives a fail.

The load terminals of the GFCI must feed only their own load and touch NOTHING else. If something touches another circuit EVEN A NEUTRAL or if a NEUTRAL touches a GROUND, the GFCI will trip.

Your options:

1. Use a 220V circuit for the timer.
2. Get a GFCI with a load neutral
3. Put the GFCI's on the sub panel breakers.

Frankly, bodies of water you are going to immerse yourself and your family i s no place for amateur guesswork with regard to wiring and protection. Get professional help.

    Bookmark   September 4, 2012 at 3:11PM
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