Lighting contactor

Therealcrt said:
Are you talking about the other contactors that work perfectly fine? Or the contactor regarding the circuits I say keep tripping when no load is connected
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The one you're having trouble with. Have you tried disconnecting one wire at a time?

Start at the breaker and see if disconnecting any one wire lets it stay on.

If so, move to the line side of the contactor, and accessible points between.
 
LarryFine said:
That's why I asked about the coil voltages matching what they're receiving.

You don't want to feed 277v to 120v coils, for example.
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All of the coils are 277 V currently I have four contactors all 30 amp three pole to 277 V coil

I have a total of 10 circuits 20A breakers each

But two of the circuits are in a same conduit, going to a pole that share a neutral. Those two circuits are on a contactor by themselves, and when I turned the circuit breakers on and cover the photocell, that’s when it destroys the contactor, keeping it in a closed position. I eliminated one of those circuits temporarily and put the other circuit and its load on a different contractor and it’s holding by itself. But again there’s no load on that circuit and when I take that circuit off and put the other one on, it also holds and does not destroy the contactor. The only issue is when both of those circuits are on a contactor whether it’s the same contactor or different contactors when they are both on and get energized, it destroys whatever contactor they are hooked up to, but when only one of the circuits is energized, it does not destroy the contactor
 
So you have 10 contactors.

Many circuits, but 2 in particular will not allow each other to be on simultaneously or they blow their respective contactors, even if they're separate ones? But it's always the contactors they're on, none of the others, even when the contactors have no load?

Even if they aren't serving a load, as in the contactor's load side terminals are cleared?

Hire a priest.

Something is getting consistently miswired. I'd carefully read through the wiring schematics for the contactors and control circuit again. There's no reason the above should happen, if I have it right. I'd need to be on-site to go through it otherwise.
 
Can you provide wiring diagrams?
What is the part number of your contactors?

The load being switched should have no impact on the coil failing. It would be a problem with contacts welding.
 
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NoahsArc said:
So you have 10 contactors.

Many circuits, but 2 in particular will not allow each other to be on simultaneously or they blow their respective contactors, even if they're separate ones? But it's always the contactors they're on, none of the others, even when the contactors have no load?

Even if they aren't serving a load, as in the contactor's load side terminals are cleared?

Hire a priest.

Something is getting consistently miswired. I'd carefully read through the wiring schematics for the contactors and control circuit again. There's no reason the above should happen, if I have it right. I'd need to be on-site to go through it otherwise.
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No, I have 10 total circuits. The contactors are three pole contactors which can withstand three circuits at 30 A each pole so I have a total of four contractors 10 circuits correct even if they aren’t serving a load whatever contactors both of those circuits are on if one circuits on contactor, A and the other circuits on contactor B and both of those circuits are on they blow each contactor, but if only one of the circuits is on, it won’t blow any of the contact
 
I did not read the entire thread but have you tested voltage at the coil wires when the photocell is activated? Sounds like you are feeding the coils with 480V. Maybe the neutral is open and being back fed through the lights?
 
Therealcrt said:
The only issue is when both of those circuits are on a contactor whether it’s the same contactor or different contactors when they are both on and get energized, it destroys whatever contactor they are hooked up to, but when only one of the circuits is energized, it does not destroy the contactor
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Sounds like you have a direct line-to-line fault between those two lines.
 
curt swartz said:
I did not read the entire thread but have you tested voltage at the coil wires when the photocell is activated? Sounds like you are feeding the coils with 480V. Maybe the neutral is open and being back fed through the lights?
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I haven’t tried that but still doesn’t seem right since everything is disconnected at the pole light hand hole and the other contactors work fine
 
LarryFine said:
That's narrowing it down. That's what troubleshooting is, a process of elimination.

Now try disconnecting one wire at a time, or disconnect all and reconnect one at a time.
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LarryFine said:
Between the two wires, anywhere between the contactor enclosure and the pole hand-hole.

If the run isn't too far, use som
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LarryFine said:
Between the two wires, anywhere between the contactor enclosure and the pole hand-hole.

If the run isn't too far, use some 12-2 NM as a temporary bypass.
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It’s a far run but also no I don’t have any continuity between any of the wires within that conduit at either side or in the enclosure of the contactors.
 
Disconnect the control voltage to the contactor those two circuits are on. Cover photo cell that turns on the other contactors. With all breakers on, check for voltage on LOAD side of the contactor that the coil is not energized. You will probably find 277 to ground, and 480 between line and load of each pole. There most likely a wrong tap that is feeding voltage from a different phase from the load side of one of the other contactors. That is what is frying your contacts. Phase to phase fault.
 
hillbilly1 said:
Disconnect the control voltage to the contactor those two circuits are on. Cover photo cell that turns on the other contactors. With all breakers on, check for voltage on LOAD side of the contactor that the coil is not energized. You will probably find 277 to ground, and 480 between line and load of each pole. There most likely a wrong tap that is feeding voltage from a different phase from the load side of one of the other contactors. That is what is frying your contacts. Phase to phase fault.
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That makes absolutely no sense of course there’s gonna be faults on the load side if the contactor is stuck in a closed position regardless if the control wire is landed or not, what do you mean by a wrong tap from a different phase from the load side of another contractor it’s completely separated. That makes zero sense.
 
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