A New One on Pool Pumps & GFCI

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Little Bill

Little Bill

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I think many have read on here of problems some are experiencing with GFCI breakers tripping from a pool pump. This seems to be from variable speed pump motors. The only solution ( if you want to call it that) is to use a special GFCI made for Pentair pool panels. In reality it is just a Siemens GFCI breaker.

I just got a call from a customer that was having the problem and he thought it was the pump motor so he bought a new one. The new pump motor also tripped the GFCI breaker, so he changed the breaker. That didn't fix it either so he called Pentair. They told him he had to get a breaker rated at 6mA. They didn't give him a brand, only that it had to be 6mA.

I told him all GFCI breakers had to be within a certain tolerance such as 4mA-6mA. I never saw one sold that had a certain mA rating. Anyway, sounds like Pentair is trying to further "pass the buck" instead of fixing their pumps.
I don't know why the customer is attempting this all himself but honestly I don't care to be in the middle of this anyway. I did tell him to get a Siemens breaker and try it.
 
I’ve had a lot of problems with those pentair VS pumps.
I’ve tried BR, Homeline, and GE breakers. No dice. I out a Siemens on it and it works flawlessly.


Sent from my iPhone using Tapatalk
 
There about has to be some sort of "noise issue" causing those trips that the Siemens units are resistant to.

The maximum thresholds for fault current on all of them per listing requirements is supposed to be the same, and I can't imagine they all aren't about the same for this aspect.
 
I've been hearing this same issue from my pool colleagues for a while now. Pentair kinda has you by the stones as you have to use their breaker.
I avoid all this. I've been Jandy RS systems for 25 years!:) I don't these issue with the Jandy VS pumps. They are very reliable and so are the RS systems.
 
The Pentair systems were originally Compool, a competing automation company. Pentair gobbled them a bunch of years ago and re-branded as their automation systems.
 
Did Siemens make a 6mA just for Pentair, or are all Siemens tuned to 6mA?
If the latter, then perhaps Pentair simply tried all the brands and found one that worked?

What happens if the panel cannot accept a Siemens gfi ocpd? Do you then have to run a sub panel and put gfi there?

Pentair needs to fix the induced "leak" current within their design.
 
FionaZuppa said:
Did Siemens make a 6mA just for Pentair, or are all Siemens tuned to 6mA?
If the latter, then perhaps Pentair simply tried all the brands and found one that worked?

What happens if the panel cannot accept a Siemens gfi ocpd? Do you then have to run a sub panel and put gfi there?

Pentair needs to fix the induced "leak" current within their design.
Click to expand...
I don't think the problem is a leakage issue as much as it is a "noise" or even RF interference issue. For some reason Siemens is more resistant to whatever interference is causing issues with others.

They all should be very close when it comes to how much fault current will trip them. 4-6 mA is not a very big window.
 
kwired said:
I don't think the problem is a leakage issue as much as it is a "noise" or even RF interference issue. For some reason Siemens is more resistant to whatever interference is causing issues with others.

They all should be very close when it comes to how much fault current will trip them. 4-6 mA is not a very big window.
Click to expand...

Doesn't noise create reactive parts?
 
FionaZuppa said:
Doesn't noise create reactive parts?
Click to expand...
That is an area I don't understand well enough to go too deep into discussion with, but unless the "reactance" causes leakage current of more then 4-6 mA, the 4-6 mA trip point isn't so much the issue as something is interfering with the control circuit of the GFCI, IMO.
 
In my opinion, it’s just abn accident that the Siemens breaker holds where others don’t. They aren’t doing anything exceptional in their design and it’s not the “6mA” issue. The UL test criteria is that it trips in 5 mA, +-1mA, so never MORE than 6mA. Siemens GFCI breakers don’t push that envelope any more than anyone else would or they run the risk of failing and losing their UL listing.

But all GFCI breakers use a little integrated circuit inside of them to electronically monitor the circuit and decide when to trip. I think that by happy accident, the algorithm used by Siemens in that IC chip happens to not react the same way as others when looking at the Common Mode noise current flow when you have a PWM device on the load side, like a VFD.
 
This has come up before in Pentair pump / GFCI related threads, but I think it's worth mentioning again:

Would the use of a common mode choke at the pump eliminate the RF interference issue with other-than Siemens GFCI breakers?

Something like this:
https://www.automationdirect.com/ad...sories/Optional_Drive_Related_Items/RF220X00A

Pass all circuit conductors (including the ground) through the choke. The AD filter recommends (4) passes, or if that won't fit, use (4) of the chokes, and pass the conductors through once each.

These could be mounted at the pump receptacle in a (oversized) j-box. Worth a try at least, and I can see no issues caused by installing the chokes.



As an alternative to try (cheaper), I used these on a recent install onboard a ship, where our venue lighting was interfering with one of the ship's navigation systems (that was a fun email to receive):

https://www.mouser.com/ProductDetai...S2BBqUJY%2bbewmVOtPmeDSObm%2b9NEK0b/5OMl3nA==

https://www.mouser.com/ProductDetai...vvnCFlh9o1Y2vYJs0k%2bn6lhm3zWnCO1rCajPMhocQ==

One each (different frequency bands) at each fixture to step on the broadband noise.

To really know for sure how to spec the ferrite(s) needed to squash the noise that's tripping the GFCI, you'd need to put a scope on the pump's circuit to see where the noise was strongest, and pick your ferrite(s) accordingly.



SceneryDriver
 
Jraef said:
In my opinion, it’s just abn accident that the Siemens breaker holds where others don’t. They aren’t doing anything exceptional in their design and it’s not the “6mA” issue. The UL test criteria is that it trips in 5 mA, +-1mA, so never MORE than 6mA. Siemens GFCI breakers don’t push that envelope any more than anyone else would or they run the risk of failing and losing their UL listing.

But all GFCI breakers use a little integrated circuit inside of them to electronically monitor the circuit and decide when to trip. I think that by happy accident, the algorithm used by Siemens in that IC chip happens to not react the same way as others when looking at the Common Mode noise current flow when you have a PWM device on the load side, like a VFD.
Click to expand...

The Siemens gfi breaker PC board looks identical to the application example of the gfci chip maker.
But, I have not dug into say a Eaton gfi ocpd to see what that PC board looks like.
It could literally be the diff between two PC board designs with varying chips used.

If it's an Rf noise issue then chokes should handle it. Certainly for a few $$ worth a shot. Ez to try, just add a jbox near the pump, pull feed wires from pump into jbox, add the choke, extend the wires (as a test). If it works, then make the choke permanent.

kwired said:
That is an area I don't understand well enough to go too deep into discussion with, but unless the "reactance" causes leakage current of more then 4-6 mA, the 4-6 mA trip point isn't so much the issue as something is interfering with the control circuit of the GFCI, IMO.
Click to expand...
Really no diff than a FM or AM antenna.

We dont know how much is added from the Rf noise. There could be 3mA leakage and then Rf noise causes another 1-2mA. The additional mA may not be real mA on the wires, could be induced within the PC board inside the ocpd, etc.

I wonder if the same issue would occur if you used std ocpd but put different type of gfci between pump and ocpd, like http://www.gfcistore.com/30-amp-inline-gfcis.html

And if it works then "you" are the goto person and "you" get to fix all the Pentair issues at customer site, etc (I know someone who sells the chokes at a good price ;)).

But, Pentair knows the issue, so why they dont include an addendum to their install instructions and include a choke?
 
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FionaZuppa said:
The Siemens gfi breaker PC board looks identical to the application example of the gfci chip maker.
But, I have not dug into say a Eaton gfi ocpd to see what that PC board looks like.
It could literally be the diff between two PC board designs with varying chips used.

If it's an Rf noise issue then chokes should handle it. Certainly for a few $$ worth a shot. Ez to try, just add a jbox near the pump, pull feed wires from pump into jbox, add the choke, extend the wires (as a test). If it works, then make the choke permanent.


Really no diff than a FM or AM antenna.

We dont know how much is added from the Rf noise. There could be 3mA leakage and then Rf noise causes another 1-2mA. The additional mA may not be real mA on the wires, could be induced within the PC board inside the ocpd, etc.

I wonder if the same issue would occur if you used std ocpd but put different type of gfci between pump and ocpd, like http://www.gfcistore.com/30-amp-inline-gfcis.html

And if it works then "you" are the goto person and "you" get to fix all the Pentair issues at customer site, etc (I know someone who sells the chokes at a good price ;)).

But, Pentair knows the issue, so why they dont include an addendum to their install instructions and include a choke?
Click to expand...



$$$$$$$$$$$$$$$$$$$ Probably realize their screw up and are chasing their tails to resolve
 
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