Control Panel Troubleshooting Help?

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TheMerkle

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Any help would be greatly appreciated:

I built the rig per the diagram below. I followed it as exactly as I could. When i finished it, I was careful to check and double check all of my circuits with a multimeter for continuity. Then, I paid an electrician to review it for me and got the greenlight.

When it came time for the big moment, I plugged it in to the outlet in my garage which is protected by a 30a GFCI breaker. The first time it popped the breaker, and I quickly realized that Amazon sent me a NC e-stop and not the NO I needed. No big deal there, with the button depressed all was well, and when twisted to release it would pop the 30a gfci in the outdoor subpanel.

So, I moved on to turn the key switch on and my luck ran out. It immediately threw the circuit inside the main panel inside the house. It didn't throw the outdoor GFCI, nor did it pop any of the fuses inside the control panel appliance (I used fast blow for every circuit).

Can anyone give me an idea where to start diagnosing this thing?
 

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For a boom like that, I suspect a dead short between the legs of power. Check the plug to make sure the wires on on the correct terminals inside of it. Those 4 wire plugs can be a booger to figure sometimes.

The only other thing I see is that the e-switch is designed to create a short and trip the gfci. Possible issue with that NC switch? It's a reach, but something.
 
I think I've ruled out the e-stop; so long as the keyswitch remains in the off position, I can plug in the appliance without tripping anything, and I can use the e-stop (albeit I'm releasing it instead of depressing it) to trip the GFCI in the subpanel and not the one in the main panel. Except for the button being wrong, this is the circuit operating as intended.

However, as soon as I turn the keyswitch, it throws the breaker in the main house.
 
It might help with troubleshooting if you could post some detailed pictures of your panel, especially the insides. There's a number of people on here with a lot of panel building experience (not me) and I'm sure someone will be able to help you.
 
I took some photos of the wiring, but they are very busy and difficult to understand. I will post them shortly regardless.

I have no doubt we will get to the bottom of things, I have already had the pleasure of learning that the forum houses many extremely well versed engineers.
 
When you switch the key switch to the on position was your 3 POS switch#1 (HLT- Boil) in the middle (OFF) position? If so then you may want to investigate LINE 1 which is your 120VAC to your PUMPS and PID.
 
Yes, as long as it's unpainted metal.

Brew on :mug:

It came with a sense gray coating on it, and then I spray painted it black. I made sure to scuff it up really well but it wouldnt be fair to say that I made sure it was bare metal.
 
When you switch the key switch to the on position was your 3 POS switch#1 (HLT- Boil) in the middle (OFF) position? If so then you may want to investigate LINE 1 which is your 120VAC to your PUMPS and PID.

I will start there and update soon. Thanks.
 
It came with a sense gray coating on it, and then I spray painted it black. I made sure to scuff it up really well but it wouldnt be fair to say that I made sure it was bare metal.
Paint is an electrical insulator, not a good enough one to use for isolating higher voltages, but good enough to add excessive resistance to the ground path. So paint on a ground contact point is a safety hazard.

However, a poor ground connection is not the cause of your main breaker tripping. That is indicative of a short somewhere.

Brew on :mug:
 
Are all of your elements and pumps unplugged from the control panel when it does this? With the panel unplugged measure the resistance between the 2 hot legs. Also what is the resistance between each leg and ground. You may need to start disconnecting stuff to zero in on the problem. I’d limit the number of times you test the circuit if you can help it. These is where additional breakers can help. I assume it’s not your pumps though since they are on individual fuses and the fuses aren’t blowing.

Are you positive it’s not a GFCI trip?

I know I’m digressing here but no professional would ever risk shorting a hot leg to ground intentionally to trip a GFCI. For one that makes the ground a current carrying conductor and it’s not supposed to be. Also that’s dangerous. It’s unfortunate that this design has been propagated here. There are better and safer ways to do an E-stop circuit if you think an E-stop is actually necessary.
 
I agree with fasttalker, isolate by taking things out of the circuit. Also a NO estop is not really an estop if the contact fails you're in big trouble. Estop should be NC. Must likely something is shorting the circuit. Without power you could check for continuity for wires that shouldn't have continuity.
 
I am a licensed electrician, and I specialize in industrial controls. I have to agree with the last two responses. You never design and e-stop NO to trip the circuit. It should be NC and should be wired first in the circuit, in series with everything else. And any time I'm troubleshooting in the field, here are some helpful tips. Walk it down. Start from the beginning with your meter, hold one lead on the neutral and move the other right down the circuit as designed, checking voltage and verifying everything. If you can't do that with power on, ohm it out using the resistance function, and check for shorts. The other thing I will agree with as stated above is this. Make sure all switches are off and everything is unplugged. Turn on main key switch. If it still trips, start from the switch. If not, power on one thing at a time until it does trip. This will isolate the problem. But before you do anything, fix that e-stop. That's a problem waiting to happen. And they're also designed to be pushed, because the first reaction in an emergency is to hit anything close. That's why it's big and red and easy to push. Good luck with everything.

*Edit* Also make sure you double and triple check the functions of the terminals on your PID. I would even put a meter on them to make sure they function properly. Those can be tricky depending on the model. Some require jumpers to work properly. It also could be a programming issue. Thanks for hearing me out.
 
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When you press an e-stop it shouldn't trip a breaker. It should only open the power circuit like a contactor. The key swich plus the e-stop are a series circuit. I agree you have a short between a power leg and a neutral.
 
When you press an e-stop it shouldn't trip a breaker. It should only open the power circuit like a contactor. The key swich plus the e-stop are a series circuit. I agree you have a short between a power leg and a neutral.
Looking at your diagram above you have the e-stop connected between hot and ground...NO.
 
For those of you arguing against the typical PJ "switched leak to ground" E-Stop: What's the difference between the operation of this circuit and the "Test" button on a GFCI breaker?

When I design in an E-Stop (I usually don't), I use an NC switch in series with the switch controlling the main power to the panel.

My main complaint with the PJ circuit is that it leaks ~60 mA to ground. It should be designed to leak more like 10 mA, since GFCI specs say they must trip at no more than 6 mA.

Brew on :mug:
 
Let's look at ohms law. I=E/R. With the design as it is shown 120VAC / 2000 ohms is 60 mA. 10 times the 6 mA. To get to 6 mA it would be 20 kohms. I wouldn't do an e-stop like this. If the resistor opens the e-stop fails.
 
When I design in an E-Stop (I usually don't), I use an NC switch in series with the switch controlling the main power to the panel.

I've never heard anyone criticize PJs designs, so I built this box as described. If there is a better way to build it, I will certainly do so. I already have the NC button you guys have described, could anyone show me this design modified to support an e-stop as you guys recommend

Are all of your elements and pumps unplugged from the control panel when it does this?

Yes. I performed my first test with all elements, pumps, and probes disconnected. Also, I made sure to set every switch to it's off position.

Also what is the resistance between each leg and ground?

No resistance between either leg and the ground on any setting. No continuity either... but am I right in my understanding that this only goes to show that the short does not exist between the contactors and the dryer cable?

I did discover that there are tabs in my 15a socket bridging the outlets together, but unless I'm mistaken, this would not cause a short. I know it will cause the panel to malfunction in that EACH pump switch will operate BOTH pumps in tandem instead of the water pump switch operating the water pump, and the wort pump switch operating the wort pump.
 
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Here is a photo of the wiring, though it's hard to imagine that anyone would be able to glean much from it.
 

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I've never heard anyone criticize PJs designs, so I built this box as described. If there is a better way to build it, I will certainly do so. I already have the NC button you guys have described, could anyone show me this design modified to support an e-stop as you guys recommend

You should be able to move the keyed switch contactor to before the Line 1 and Line 2 terminals. And then wire the NC e-stop in series after the keyed switch like doug said. With it wired this way you’ll only have power to the power-in receptacle when you hit the e-stop and it will no long trip your GFCI.
 
Thanks for everything so far guys. As it stands, I have moved the e-stop such that it runs in series with the keyed switch, and I have removed the jumper tabs in the pump outlets.

After doing this I retested everything for continuity and shorts, and as best I know how to test it, it checked out.

Still, when connected to power with nothing plugged in and every switch turned off, everything is fine, but turning the key switch throws the main breaker in the house without burning any fuses in the appliance, or throwing the GFCI breaker in the outdoor subpanel.

Any ideas?
 
Thanks for everything so far guys. As it stands, I have moved the e-stop such that it runs in series with the keyed switch, and I have removed the jumper tabs in the pump outlets.

After doing this I retested everything for continuity and shorts, and as best I know how to test it, it checked out.

Still, when connected to power with nothing plugged in and every switch turned off, everything is fine, but turning the key switch throws the main breaker in the house without burning any fuses in the appliance, or throwing the GFCI breaker in the outdoor subpanel.

Any ideas?
Check and make sure you are connecting between hot and neutral, not ground. I would check to see if there are any updates on the schematic.
 
I don't know what you have to test with or how comfortable you are testing something hot. I would disconnect all the grounds from any device while leaving the main power ground in place. Tape all ground wires. Once all other grounds are disconnected. Connect the power and turn on the key switch. If it trips still we need to look somewhere else. If it doesn't disconnect power and one at a time read between the main power ground and the taped grounds one at a time. Disconnect power (unplug) each time you change to each wire. You can also replace any grounds that don't show power.

If you find one trace it back to the device and verify all connections. Remember with the device grounds disconnect a device may be hot but the panel is still grounded. If you lift all the grounds and you still trip you more than likely have a device that is shorted to the panel.
 
I think the problem is more likely a power to power or power to neutral short. If anything were shorted to ground, it should trip the GFCI. GFCI's are designed to trip faster than normal breakers (since people get hurt much quicker than wires, and GFCI's are to protect people, and breakers are to protect wires.)

Brew on :mug:
 
Might be a little late, but it is a good idea to build things up in blocks and test as you go.

Also to help troubleshooting wiring, print out the schematic/wiring diagram and use a highlighter to highlight the connection as you check them out. That also works for initial assembly too.
 
What brand are your contactors and what coil voltage are they? Did they come with a pin layout? I was trying to follow your pic you have posted of your panel but some of wiring is hidden behind other wires. Maybe another couple of pics from different angles might be helpful.
 
My diagram, after the E-stop modifications I made, looks like this now:
 

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I think the problem is more likely a power to power or power to neutral short. If anything were shorted to ground, it should trip the GFCI. GFCI's are designed to trip faster than normal breakers (since people get hurt much quicker than wires, and GFCI's are to protect people, and breakers are to protect wires.)

Brew on :mug:
So to check what Doug is saying. Lift the connections coming off point 2. That will eliminate line to line. But this will allow the control power to turn on the main contactor. If you lift line 2 connection and if it still trips you have a line to neutral problem.
 
Just to rule out another potential problem: switches and relays dont care about polarity right?
In most cases, "in" vs. "out" doesn't matter for a mechanical switch. If using a double throw switch for selection purposes, then what's connected to what can make a big difference.

Brew on :mug:
 
So to check what Doug is saying. Lift the connections coming off point 2. That will eliminate line to line. But this will allow the control power to turn on the main contactor. If you lift line 2 connection and if it still trips you have a line to neutral problem.

Instead of removing all of the line 2 connections, could I just remove the line 2 supply wire where it comes into the box to the same effect? Then, test it that way to rule out hot to hot shorts?
 
Instead of removing all of the line 2 connections, could I just remove the line 2 supply wire where it comes into the box to the same effect? Then, test it that way to rule out hot to hot shorts?
Can't hurt to try.

Brew on :mug:
 
so one important question, do you have a 4 wire breaker box with an isolated ground ??

It's the same receptacle I used for the previous box I built. Though, that box box didnt use the neutral leg at all. I'm not sure if that rules out the outlet.
 

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