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Pond pumps tripping GFCI

14K views 23 replies 4 participants last post by  Scuba_Dave 
#1 ·
I have been visiting this site and searching its forums for a while now and thankfully I have found all of the information by reading other threads. Today is the day that did not occur and I have now joined this community to find help. I will be a contributing member before long so looking forward to meeting you.

I have a waterfall with two identical pumps that were working just fine until recently. This is installed on it's own 20 amp circuit.

1. The 20 amp breaker to 20 amp gfci has 14/2 wired. Isn't that under sized?

2. From GFCI to Intermatic t101r off of the load end of receptacle--therefore I have benefit of GFCI protection, right? Or should pumps not be protected by GFCI?

3. When pumps switch on with timer, GFCI trips after about 20 seconds. If I reset and restart timer, GFCI trips after .5 second. Does this help at all?

4. Can I test pumps with a multimeter, and if so how do I do that?

5. Being that the wire ran is 14/2, and the pumps each pull 6 amps, could this cause the GFCI to trip just by the starting of the pumps? Would any debris in the pumps such as leaves cause this as well or is it probably a bad pump?

6. I removed one pump from the circuit and the system is fine. If I remove and replace the working pump with another identical pump, the GFCI trips after 5 minutes. Then when I reset the GFCI this happens immediately. Any ideas?

Thank you for your help in advance. If a diagram is needed let me know.
 
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#2 ·
For a 20a breaker you do need #12 wire.....the #14 is undersized & does not meet code

I wire my Intermatic timers w/GFCI after the timer
Ponds should be protected w/GFCI, especially if people can stick their hands in the water, of if you will have fish

2 pumps 6a each = 12a
Not beyond the capacity of the #14 wire or the breaker
You could install a 15a breaker
is 6a the Max draw for the pumps ?
 
#6 ·
Are these pumps the only devices on this circuit?

I'd start by replacing your wiring. 14/2 should only be used with a 15A breaker. You need 12/2 if you are using a 20A breaker. You've also indicated that you have a 12A load on the circuit (two 6A pumps). That matches the ampacity of 14AWG copper (80% of 15A on continuous load). I'm also assuming that the 12A load is a continuous rating; if the start-up load is higher, you could easily be exceeding 15A momentarily (but not tripping the breaker because it is oversized; in fact, I wonder if the original breaker was a 15A and was swapped for a 20A to avoid start-up trips).

My suspicion is that your wiring/connections has degraded because you've been drawing more current than 14/2 can handle, and has now created a ground-fault condition. The breaker hasn't tripped because it is overrated against the ampacity of the wire. Replacing the breaker with a 15A single-pole will match the capacity of the wire, but wouldn't do anything to change the fact that you're putting a 12+ amps load on the circuit.

Where is the GFCI outlet located? If it is an outdoor outlet, it must be GFCI, regardless of what load you use on it. Are you sure it is a 20A receptacle? Most residential GFCIs are rated 15A at the receptacle with 20A pass-through, but cannot support a direct 20A load plugged directly into it.
 
#9 ·
Quote - clashley

I'm also assuming that the 12A load is a continuous rating; if the start-up load is higher, you could easily be exceeding 15A momentarily

Typical motor starting load are 7 x FLA but this only lasts 1/10 sec, the OP stated he was tripping the GFCI not the panel breaker. I suspect one of the pumps is shorting after the feild winding heat up.
 
#11 ·
That's a good possibility, especially since the GFCI won't trip on an overload, but that 20A breaker is not going to trip before cooking the 14/2 feeder anyway. The breaker/feeder mismatch needs to be addressed, and based on the described load, I'd say it needs to be brought up to 20A. A 12A continuous load will stress the capacity of 14/2 over time and probably eventually lead to failed connections (or worse).
 
#15 ·
The OP said he has two 6A pumps plus a LV lighting transformer on the load side of the GFCI. The load of the two pumps alone equals the permitted continuous load ampacity of 14/2 per NEC, which is limited to 12A/1440W. Add in the LV transformer, and it's out of code (not to mention the overrated breaker).

Can he get away with it? Probably (but at least swap out that 20A breaker), but it is technically not legal and I wouldn't be comfortable with it in my own home.

In order to support the described load, a 20A breaker with 12/2 is necessary to meet code. That would bring the capacity of the circuit on continuous load to 16A/1920W, which is adequate for the described 12A+ load.
 
#7 ·
The pumps and a 200 watt transformer for low voltage lights inside of the pond are the only devices on this circuit. The problem occurs with or without the transformer plugged in.

This is all outside. I just read another thread elsewhere that had suggested bypassing a gfci for devices with a high start up load.
 
#13 · (Edited)
Additional information:
I brought the two pumps into the store where I purchased them and they connected the pumps to their line and ran the pumps individually for a good while. However, this was above water.

what does "field winding up" mean?
"Field winding heat up" - field windings are the stationary windings internal to the motor that create the opposing magnetic feild that force the rotor spin.

Did the store run them on a GFCI?

With no water pumping the pumps have only have rotation resistance and ineritia loads, say 10% of the load they experience when they are pumping.

You could try and run (while pumping water) the problem child on an extension cord (no GFCI) and see if it eventually shuts down on either a thermal overload or trips the breaker. (that is if there are no fish in the pond, and keep your hands out of the water and supervise the area while running it)

My bet is the latter.

I agree with scuba dave 14/2 will run that load, but the wire is not protected properly, change the breaker or the wire, don't leave it like that as it could be a possible fire hazard.
 
#16 ·
No fish but finding a non GFCI source is hard to come by because it's almost 150' from the closest source. A thermal overload is when the pumps just stop but the breaker is intact, correct?
Yes the pump will stop and after the winding cool down it will run again.

150 ft - long way to run, is that how far the 14/2 runs as well? If you are running that far away, the amps on those pumps while running will be higher due to a lower voltage (voltage drop under load), this will cause premature pump failure (field winding failure) because of excess heat.
 
#17 ·
not running 14/2 that long. There is another main out in that area because the previous owner had an idea of building a large garage but just ran electrical there when the house was built and then built a small patio area with a fountain. I guess I could come off the board directly with 12/2 and 20 amp breaker and see what happens after a half hour or so.
 
#18 ·
not running 14/2 that long. There is another main out in that area because the previous owner had an idea of building a large garage but just ran electrical there when the house was built and then built a small patio area with a fountain. I guess I could come off the board directly with 12/2 and 20 amp breaker and see what happens after a half hour or so.
Yes but you have to promise that you won't leave it like that! GFCI's don't protect the wire or equipment they protect you or any other unsuspecting soul who may get close enough to be electocuted because of a bad conductor.
 
#19 ·
Of course I wouldn't leave it like that. I understand that the circuit needs different wiring but I want to check if the pumps are causing the problem too. Why fix the electrical right away when I will still need one, or maybe two new pumps costing over $500?
 
#22 ·
I don't see any problem with a 200w lighting load & a 12a pump load on wire rated to carry 1800w
And its possible the pumps do not run at 6a load
The breaker or the wire need to be replaced to meet code

If you can I'd disconnect each pump too see which one is causing the problem
 
#23 ·
Sorry, but #14 wire is not rated at 1800w for a continuous load. The max continuous load (3 or more hours) for #14 is 1440w.

I am working on the assumption that the pumps are programmed to run for several hours, since they are used for a waterfall, which is why I am asserting that the #14 wire must be derated to its continuous load ampacity. Unless the timer is programmed is cycle the pumps so that they never operate more than 3 hours at a time, the pumps alone equal the permissible continuous rating of that circuit. Any additional load creates a violation.

Even if the pumps actually operate at under 6A, the NEC does not care. The ruling value will be, at minimum, the amps/wattage stamped on the device. The OP also stated that he has about 150' of line between the motors and the breaker, and not all of it is #14. There will be voltage drop associated with the length of line, which means the current draw will increase.

In this particular situation, at least one of the motors appears to be ground-faulting once it heats up, which could increase the current draw even further. With a 20A breaker, it's unlikely to trip before the wire melts.

I can't see an inspector signing off on this type of setup unless 12/2 is used with a 20A breaker. The other option would be to switch the breaker down to 15A breaker and use pumps with lower-rated power draws.
 
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