defective SSR?

I am having a problem where every time I turn on the 220 to my control box the GFI is tripped. We narrowed down the issue to the SSR since we have bypased everything else w/o the GFI tripping. What is also strange is if the 110 is turned off and the 220 is on (ie SSR doesn't have 110 to flip the relay)I measure 110V at both of the SSR outputs.

Questions:

1. Is the SSR defective?

2. What would be wrong with the SSR to cause the GFI to trip?

3. Shouldn't there be 110V at just one of the SSR outputs if the relay isn't flipped?

Clear one thing up, the input to the SSR is 120Vac??? That's odd, it's usually 4-30Vdc required to turn it on. I don't think I've ever seen one with 120V control. Check that out, you may have destroyed it.

pp270 said:

1. Is the SSR defective?

2. What would be wrong with the SSR to cause the GFI to trip?

3. Shouldn't there be 110V at just one of the SSR outputs if the relay isn't flipped?

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1. Possible, but unlikely. Especially if it's brand new.

2. Wiring error somewhere, probably. GFI trips when there's a current loss to ground or another circuit. Doesn't take much - a few mA.

3. Yes there should be voltage across the SSR when off. SSRs switch current, not voltage. Use a load to verify SSR output - like a house lamp - instead of a multimeter.

There is 10-15V going to the SSR as the 110 goes through the PID which then steps it down to the proper input voltage for the SSR. The input voltage to the SSR was verified.

The ssr is brand new. I went over the wiring quite extensivly and bypassed everything w/o the GFI tripping. Plug in the SSR and as soon as it switches the GFI flips.

I will try your recommendation on the load for the ssr.

Can you think of anything internal to the ssr that could flip the GFI? Would the rate at which it switches possibly cause a trip. I know this is a variable on the PID.

Do you have only the 240 into your control box (i.e., are you also running a 120V ckt in there?)

Do you have a ground wire (separate from your white neutral) going into the box? What exactly is this connected to? It should NOT be connected to anything but the metal chassis.

Is it the GFI or the breaker that is tripping? These mean entirely different things.

A defective SSR should NOT trip the GFI unless there is a short somehow to the heat sink, which is then touching a grounded part of the box.

Is the GFI in your breaker box, or is it an external cord or box you bought?

Ok I have attached a schematic as it is wired now to answer alot of questions. I hand wrote in the ground connection for the BK and heater plug in. Also a 20amp fuse to the PID and a 30 amp fuse to the SSR.

Please review and advise if anything looks incorrect. Or if anything that you see might be cause of the GFI tripping.

To answer some of the questions in the previous post:
My GFI protection for the 240 is located in the breaker box as it is a 30 amp gfi breaker. Yes just the GFI flipped not the breaker. I have a PVC box and all the grounds shown on the schematic go to a seperate ground bar and no the SSR heat sink is not connected to the ground bar in any way.

Did you know if you bring the 240V neutral into the box you can take 120 off one leg of that 240V circuit? I.e., you don't need the 120V separate ckt coming into the box.

Does the GFI trip if the 120 is completely disconnected from the box?

sure I did, but wanted to have two seperate circuits for the 120 and 240 in the box.

The GFI only flips when the SSR indicator light goes on (ie switches) which of course you need the 120 for. So no the GFI doesn't flip when the 110 is off.

Does the wiring in general look ok?

pp270 said:

Does the wiring in general look ok?

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yea, looks OK. I'ts a little confusing following it through there.

Out of curiosity, what did you do with the 240 neutral (white)?

capped off at the wall plug in. I only have three prong outlets.


Does anyone else know if anything on my wiring schematic would be causing the GFI to flip?

The only thing I Can think of is take your multimeter and check for continuity to ground at the ssr load terminal , and at the load. I can see a few places in your wiring diagram but nothing that would cause a problem.

I found the problem it was the GFI wiring. The electrician ran the neutral through the breaker when I am not using it. Disconnected this and everything is working good.

I would have never guessed that in a million years.

pp270 said:

I found the problem it was the GFI wiring. The electrician ran the neutral through the breaker when I am not using it. Disconnected this and everything is working good.

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The 240V neutral definitely should run through the GFI. I guess if it is not used, you don't need to connect it.
Are you sure there isn't anything else on that circuit in your house?

passedpawn said:

The 240V neutral definitely should run through the GFI. I guess if it is not used, you don't need to connect it.
Are you sure there isn't anything else on that circuit in your house?

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Ah. The way he posted it the electrician 'breakered' the neutral. I wasn't going to touch that one.