Tripping hot tub breaker

[kwired]

I disconnected the EGC feeding the tub. Touching the EGC back to the ground bar on the tub with the motor running trips the breaker.

Thank you

That confirms whatever the fault is, it is returning to the source via the EGC.

Does not have to mean it is the motor, it could be anything that also changes state when that motor is running.

 

[Jraef]

If you removed the heater leads and it only trips when the motor runs, AND the motor has been changed with no effect, that really narrows it down to only two things, one of which you also have not mentioned exists or not; the leads going TO the motor, or an ozonator, if there is one, because it too would only be powered when the motor runs. So if there is an ozonator, disconnect it and see if the problem goes away. If not, or there isn’t one, then it has to be the wires from the controller to the motor.

I agree with the others, replacing the feeder conductors is a total waste of time and money, other than you getting paid to do it. That wouldn’t be effecting the GFCI breaker unless that breaker is AHEAD of the entire feeder circuit.

 

[Ditcher]

Indeed,
The Electric heater is most times the culprit.
Cause bad water chemistry.
We have seen folks eat heating elements in 3 months.

 

[goldstar]

I agree with all those that said it is probably the heaters or the ozonator. However, until you find out whether the breaker is tripping on a ground fault or an overload you'll be spinning your wheels. I would disconnect ALL the ground wires at the control unit to start off with and then run the tub. If it continues to run without tripping the GFI breaker then in all likelihood you have a ground fault problem. I would then start reconnecting one ground wire at a time to locate the problem. If it trips without the ground wires on you may have an intermittent short circuit or some other type of overload. If that's the case clip an amp-probe on the feed wires, turn on one motor at a time and see which one is causing the problem. Good luck.

 

[ptonsparky]

I agree with all those that said it is probably the heaters or the ozonator. However, until you find out whether the breaker is tripping on a ground fault or an overload you'll be spinning your wheels. I would disconnect ALL the ground wires at the control unit to start off with and then run the tub. If it continues to run without tripping the GFI breaker then in all likelihood you have a ground fault problem. I would then start reconnecting one ground wire at a time to locate the problem. If it trips without the ground wires on you may have an intermittent short circuit or some other type of overload. If that's the case clip an amp-probe on the feed wires, turn on one motor at a time and see which one is causing the problem. Good luck.

Be careful with this method. The GFCI is apparently working, but you will feel the current available when you place yourself in series with it. HLH (hurting like heck), you may jerk back then lose your balance and fall into the cactus garden.

 

[WSB123]

If you removed the heater leads and it only trips when the motor runs, AND the motor has been changed with no effect, that really narrows it down to only two things, one of which you also have not mentioned exists or not; the leads going TO the motor, or an ozonator, if there is one, because it too would only be powered when the motor runs. So if there is an ozonator, disconnect it and see if the problem goes away. If not, or there isn’t one, then it has to be the wires from the controller to the motor.

I agree with the others, replacing the feeder conductors is a total waste of time and money, other than you getting paid to do it. That wouldn’t be effecting the GFCI breaker unless that breaker is AHEAD of the entire feeder circuit.

I went back and checked the hot tub again. I disconnected the ozonator and the element. Trips instantly when the motor is turned on. I reconnected the ozanator and element.
The motor is a 120 volt / 2 speed unit. Unplugging the unit, I tested the pins on the circuit board and had 124 volts L1-N and to ground. Same voltage on L2. 0 volts ground to Neutral.
I plugged the motor back in and disconnected the EGC. Motor runs. As soon as EGC touches the ground bar the GFI breaker trips. I reconnected the EGC and cut the ground lead going to the motor. The motor ran without issue for about 15 minutes before I turned it off. With the motor running, I tested the voltage and discovered that measuring from L1 and L2 (from the main terminal block) to the ground wire I cut coming from the control board side I had 124 volts from each. I did so as a second test to verify the board was good.
I then checked voltage from the ground lead coming from the motor to the EGC and measured 26v. I assume that the motor is the source of the problem, although the spa technician has recently replaced it.
Any thoughts? Any I missed? Otherwise, I am done and it goes back the technician to replace the motor again. I told them to also replace the wire from the board to the motor.

Thank you for your input.

 

[goldstar]

Be careful with this method. The GFCI is apparently working, but you will feel the current available when you place yourself in series with it. HLH (hurting like heck), you may jerk back then lose your balance and fall into the cactus garden.

AND, make sure you have the camera rolling when you do this.

 

[goldstar]

I plugged the motor back in and disconnected the EGC. Motor runs. As soon as EGC touches the ground bar the GFI breaker trips. I reconnected the EGC and cut the ground lead going to the motor. The motor ran without issue for about 15 minutes before I turned it off.

Bingo :thumbsup::thumbsup::thumbsup:

 

[kwired]

I went back and checked the hot tub again. I disconnected the ozonator and the element. Trips instantly when the motor is turned on. I reconnected the ozanator and element.
The motor is a 120 volt / 2 speed unit. Unplugging the unit, I tested the pins on the circuit board and had 124 volts L1-N and to ground. Same voltage on L2. 0 volts ground to Neutral.
I plugged the motor back in and disconnected the EGC. Motor runs. As soon as EGC touches the ground bar the GFI breaker trips. I reconnected the EGC and cut the ground lead going to the motor. The motor ran without issue for about 15 minutes before I turned it off. With the motor running, I tested the voltage and discovered that measuring from L1 and L2 (from the main terminal block) to the ground wire I cut coming from the control board side I had 124 volts from each. I did so as a second test to verify the board was good.
I then checked voltage from the ground lead coming from the motor to the EGC and measured 26v. I assume that the motor is the source of the problem, although the spa technician has recently replaced it.
Any thoughts? Any I missed? Otherwise, I am done and it goes back the technician to replace the motor again. I told them to also replace the wire from the board to the motor.

Thank you for your input.

Since motor has already been replaced, I'd be looking harder at wiring between motor and control board before just throwing another motor at it.

 

[growler]

Since motor has already been replaced, I'd be looking harder at wiring between motor and control board before just throwing another motor at it.

You could replace that wiring first but it could always be a bad motor. Just because something is new we expect it to work but that's a matter of quality control at the manufacturers and is not always so good.

I think I would call the manufacturer of the motor and see if they have had any such problems with new motors. A few times they have been honest and admit there may be problems with new product. The darn thing may be on a recall list.

 

[goldstar]

You could replace that wiring first but it could always be a bad motor. Just because something is new we expect it to work but that's a matter of quality control at the manufacturers and is not always so good.

I think I would call the manufacturer of the motor and see if they have had any such problems with new motors. A few times they have been honest and admit there may be problems with new product. The darn thing may be on a recall list.

That would be my guess

 

[kwired]

You could replace that wiring first but it could always be a bad motor. Just because something is new we expect it to work but that's a matter of quality control at the manufacturers and is not always so good.

I think I would call the manufacturer of the motor and see if they have had any such problems with new motors. A few times they have been honest and admit there may be problems with new product. The darn thing may be on a recall list.

I could meg the wiring harness and the motor faster then I likely can get such response from manufacturer, and at that point should know which one is the problem.

 

[LarryFine]

You can also test the motor by disconnecting power to it as close to the motor as you can. With everything else running, connect that wire.

One other possibility is most hot tubs have a flow switch to protect the heater in case water flow stops. Its wiring could have leakage to ground.

 

[paynee]

I have a customer with a 50 amp / 240 volt hot tub. The tub was tripping the breaker and the hot tub company replaced the motor. The tub would run for a few minutes, but then would trip.
It now trips as soon as the motor is turned on. After replacing the motor with the same results, he has replaced the circuit board as well. The breaker still trips. The lights will turn on without issue.
As the electrician, I looked at the tub after the other guy came to the end of what he knew to do. I have not done a thorough search, but the first thing I did was to disconnect the ground wire at the tub. The motor runs. At that time, I checked the voltage between the neutral and ground - 0 volts. As soon as the ground wire is connected, the motor trips.
The customer has had several electrical issues due to poor workmanship in the past that we have already remedied, so he asked us to replace the supply wire from the panel to the hot tub disconnect and to the tub. I told him replacing the incoming line to the breaker would not alleviate the problem because the breaker is detecting ground faults south of the breaker, not the incoming line, but we replaced it for his peace of mind.
The hot tub technician called tech support for the tub and they think there is an electrical issue within the house. Tech support recommended turning off all breakers to see if power was feeding back to ground.
My first question: If this were an issue, wouldn't it cause other ground faults to trip? (hot tub tech support says voltage going back to ground would not necessarily trip the ground fault receptacles, because they are different from the hot tub breaker - How so? ) By the way, with all breakers off, the hot tub still trips.
Second question: What is the best way to check the system for any "voltage leaks" if there are any? I am not getting any readings between neutral - ground.

Thank you for your input.

Tech support talking cr-p. Earth faults are related to leakage currents not voltage. FVOD's(fault voltage operating device) have not been used for some time, mainly due to the fact that under fault conditions, any FVOD in the in the vicinity could trip even though not on same circuit or installation. Parallel earth paths.

 

[paynee]

I have a customer with a 50 amp / 240 volt hot tub. The tub was tripping the breaker and the hot tub company replaced the motor. The tub would run for a few minutes, but then would trip.
It now trips as soon as the motor is turned on. After replacing the motor with the same results, he has replaced the circuit board as well. The breaker still trips. The lights will turn on without issue.
As the electrician, I looked at the tub after the other guy came to the end of what he knew to do. I have not done a thorough search, but the first thing I did was to disconnect the ground wire at the tub. The motor runs. At that time, I checked the voltage between the neutral and ground - 0 volts. As soon as the ground wire is connected, the motor trips.
The customer has had several electrical issues due to poor workmanship in the past that we have already remedied, so he asked us to replace the supply wire from the panel to the hot tub disconnect and to the tub. I told him replacing the incoming line to the breaker would not alleviate the problem because the breaker is detecting ground faults south of the breaker, not the incoming line, but we replaced it for his peace of mind.
The hot tub technician called tech support for the tub and they think there is an electrical issue within the house. Tech support recommended turning off all breakers to see if power was feeding back to ground.
My first question: If this were an issue, wouldn't it cause other ground faults to trip? (hot tub tech support says voltage going back to ground would not necessarily trip the ground fault receptacles, because they are different from the hot tub breaker - How so? ) By the way, with all breakers off, the hot tub still trips.
Second question: What is the best way to check the system for any "voltage leaks" if there are any? I am not getting any readings between neutral - ground.

Thank you for your input.

Tech support not correct. Earth leakage protection provided by Residual Current device (rcd) not fault voltage operating device (fvod). FVOD old technology because neighbours could trip under your fault conditions

 

[roger]

This thread is 3 years old, you can start a new thread on the subject if you like.

Roger