Low Voltage Circuit Breaker Tripped While Only the Switch for the Control Panel is ON

Just to confirm, the next steps for me are:
1. Leave the black connector unplugged.

Plug this connector back in...

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2. Unplug both of the black terminal blocks on the comm ports (marked in the green rectangle). Just to clarify, do I simply unplug them using force, or is there any need to unscrew anything?

The connectors pull straight up from the board. Nothing to unscrew.

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No, sorry... The black plug test is done and you can reconnect it now and leave it connected going forward. (The black plug supplies the three different voltages required to rub them main board, relays and valves)

And for the comm port terminal blocks... Don't unscrew anything, the whole block pulls off. It mates to a set of pins that are soldered to the board
 
Whoops. Stupid phone didn't show the latest replies.

Ok now that we know the board runs with the comm ports disconnected, you need to figure out which device is causing the problem... If you know which wire goes to your indoor controller, plug in the other block and see if it still works. Then repeat the exercise for the other devices you've got. Hopefully it's just the indoor that's broken
 
"you need to figure out which device is causing the problem..."

Yes, I came to the same conclusion after the last step, but I still have a question. My understanding is that when all the breakers for the pool equipment are in the OFF position, there shouldn’t be any electrical flow between the control panel and the equipment. So, how is the panel still ‘sensing’ an issue with the equipment?

Regarding trying one device at a time, I’m not quite sure how to proceed. Where are the other blocks, and where exactly should I plug them in to test each device? sorry i know this might be a dumb question...
 
"you need to figure out which device is causing the problem..."

Yes, I came to the same conclusion after the last step, but I still have a question. My understanding is that when all the breakers for the pool equipment are in the OFF position, there shouldn’t be any electrical flow between the control panel and the equipment. So, how is the panel still ‘sensing’ an issue with the equipment?

If you know which wire goes to your indoor controller, plug in the other block and see if it still works. Then repeat the exercise for the other devices you've got. Hopefully it's just the indoor that's broken

Your indoor controller is powered when you turn on the outdoor panel. @ogdento suspects that is the culprit.

Regarding trying one device at a time, I’m not quite sure how to proceed. Where are the other blocks, and where exactly should I plug them in to test each device? sorry i know this might be a dumb question...

You have two blocks here. One block has one cable connected to it. The other has two cables connected.

Which block is the cable to the indoor controller?

Connect the other block that is not the indoor controller.

screenshot-2024-08-17-at-2-10-38-pm-png.604624
 
Got it. I wasn’t sure which block powers my indoor controller, so I plugged back in the left one (the one with 1 black wire). The indoor unit beeped once, turned on, and stayed on (first photo).

So it seems like the indoor unit is functioning properly?

I’m suspecting the issue might still be on the pump side (As I mentioned earlier, the junction box was missing the top insert (last photo), and there was water in the conduits(second and third photo). I’ve already removed the conduits and plan to replace everything there. Although I don’t understand why this is happening when the breaker switch for the pump is in the OFF position).

How can I completely disconnect the pump from the panel? Thanks!
 

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Ok. we are making progress.

So now we have the connector with two cables going into the screws. Disconnect one of the cables from the connector and them plug in the connector to the board.

If the CB trips you found the bad cable.

If the CB does not trip then remove the good cable from the screws and connect the other cable and the CB should trip confirming that is the bad cable.

As to why this is happening even with no power to the pumps, somewhere along the bad cable the wires are shorted causing the CB to trip. The board puts voltage on the black and red wires on that cable.

Replace the bad cable and a good chance this problem should be fixed.
 
While you are in the panel label the cables as you learn where they connect to. It will help you with the next problem.
 
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When you redo the wiring, I suggest using WAGO connectors and Gelboxes instead of wire nuts. The Gelboxes seem to be truly waterproof. My j-box fills with water during heavy rain, so the connectors are fully submerged. Yet the Gelboxes keep the connectors dry.
 

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Okay, it looks like we’re making real progress now.

As @ajw22 mentioned, I’ve identified the bad wire—one of the two black wires that triggered the breaker.

Now the challenge is figuring out which piece of pool equipment this wire connects to. I tried to trace it, but I’m stumped. Any suggestions?

I have a total of 5 pumps, two gas heaters, an in-pool light, an IntelliChlor IC40, and a yard landscape lighting system connected to this panel. :ROFLMAO:

I suspect the pump with the soaked wire might be the culprit, but how can I temporarily disconnect it from the panel to test if the breaker trips?

And just to confirm, we’re certain the issue is outside the control panel itself, correct?
 
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I'm assuming the black wire you found is one of the black wires that connects to one of those comm port blocks? But I may be missing something... I'm not sure why it's hard to figure out where it goes?

Few points:
- The pumps shouldn't use the comm port red/black at all
- I would bet your landscaping doesn't use the comm port red/black
- Does your gas heater connect to the comm port?
- I didn't know you had an intellichlor... my guess is one of those comm cables runs to the "surge board" in the back of the top section of your outdoor panel. you could disconnect that
 
you can check this blog post for more details on the comm port wiring...

I've got a sub-title of "Step 1: Is everything connected?" that talks about how to test for continuity and shorts
 
"I'm assuming the black wire you found is one of the black wires that connects to one of those comm port blocks"
-That is correct, after pulling out one black wire on the com connector, the panel turns on without tripping.
-I was wondering can i just leave that wire unplugged? That might cause some safety issue?

"I'm not sure why it's hard to figure out where it goes?"
-I traced the wire and it goes into a conduit with a bunch of other wires, so I have no idea where they are going to.

"Does your gas heater connect to the comm port?"
-I will need to find out, i was trying to trace more and found a wasp nest right around the landscape control panel, need to kill the wasp tonight first.
 
Yes, you can leave the wire disconnected from the board without any problem.
 
“Yes, you can leave the wire disconnected from the board without any problem.

My real concern is that if the low voltage circuit keeps tripping and I don’t find and fix the issue, could there be a risk of getting shocked, burning the wires, or even causing a fire? :oops:

On the other hand, I’m not planning to use the spa or heaters, so I’ll keep their breakers in the OFF position and only turn on the breaker for the pool pump.

If the pumps don’t use the comm port red/black wires, does that mean the pump isn’t the reason the panel is tripping?
 
the black wire is ground and the red is +15vdc for the low-voltage supply, so if the 12vac low voltage breaker no longer trips with the black wire removed AND everything is working... whatever that particular comm port cable connects to is only using the green/yellow data lines and not using the red/black low voltage power supply (otherwise you'd see a device not functioning).

In which case you can pull both the black and red wires out of the terminal block... snip them off or tape them up if you're worried about it. Remove both the red and black... otherwise the red wire will still be energized (even though it's not being used) and could at some point short to the green/yellow data lines and damage the outdoor board and/or anything on the comm port

If the pumps don’t use the comm port red/black wires, does that mean the pump isn’t the reason the panel is tripping?
the pump isn't the problem, but the wire TO the pump could be the problem. you've determined that the low voltage breaker is tripping because there's too much current being drawn from the red/black supply... if the red/black are connected to the comm port, whether they are used or not, there will be 15 volts across them... and it'll draw too much current if the black is shorted to red (as it appears to be in your case), OR if the pump data lines were shorted to red or black... but if the data lines were shorted then your pumps couldn't talk to the outdoor board. if your pumps are showing "Display not active" when the comm cable is connected to the outdoor board then they are working.
 
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Thanks! Although the low voltage circuit stopped tripping after removing the black COM wire, I haven’t yet tested if everything is working properly since only the switch for the panel itself is currently on. All other pool equipment switches are in the OFF position, and i plan to change out the junction box, wires inside, new conduits...etc.

This year, I only plan to turn on the pool pump, so I’ll be happy as long as that works. I don’t intend to use the heater, spa, or pool robot (I’m planning to replace the current pump-driven robot with a battery-powered one).

"your pumps couldn't talk to the outdoor board" "if your pumps are showing "Display not active""
I’ve replaced the original old Sta-Rite pool pump with a V-Green pump, which I believe doesn’t have the capability to communicate with the Pentair control panel.

Thank you so much for all the advice—it’s been really helpful!
 
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