Square D Arc Fault

[kwired]

Cutler Hammer does make a AFCI that is the same size as regular breakers. The other day the counter guy asked me which one I wanted, and I said the small one, and wha la he handed me one.

CH or BR series?

 

[electricguy61]

The problem the inspector noted (though I agree it's not a legitimate code violation) is one of the reasons I stopped using SqD Homeline.

Another was the constant call backs on AFCI nuisance tripping. Murray/Siemans seem to be less prone to that problem.

I also like that I can easily remove the exterior doors on Murray panels. Makes it easier to wire up.

And Siemans added a 42 circuit panel to their meter/panel series. You need all the spaces you can get now!

 

[jmellc]

The problem the inspector noted (though I agree it's not a legitimate code violation) is one of the reasons I stopped using SqD Homeline.

Another was the constant call backs on AFCI nuisance tripping. Murray/Siemans seem to be less prone to that problem.

I also like that I can easily remove the exterior doors on Murray panels. Makes it easier to wire up.

And Siemans added a 42 circuit panel to their meter/panel series. You need all the spaces you can get now!

Nuisance tripping, on new installs or rewires? I don't recall any Homeline issues I've had like that. I had a trouble call several years ago that an AFI kept tripping, I think it was a GE brand. New breaker tripped also. I narrowed it to a bed headboard with radio, clock & lights built in. Unplugged that & everything worked fine. I metered the eqpmt for neutral/ground fault but found nothing there. Put it on a drop cord & checked load. Full load was 3 or 4 amps, certainly no heavy draw.

I saw a similar issue years ago in a school. A projector would trip a GFI breaker, plugged into a protected receptacle at a work table. We wound up putting in a ceiling recept & they did an overhead mount.

I have often seen refrigerators and freezers start tripping GFCI receptacles after the appliance ages a few years. I used to change to std recept, then after code change, started installing GFCI breaker. Breaker much less nuisance tripping than receptacle.

 

[kwired]

I have often seen refrigerators and freezers start tripping GFCI receptacles after the appliance ages a few years. I used to change to std recept, then after code change, started installing GFCI breaker. Breaker much less nuisance tripping than receptacle.

Every refrigerator or freezer I have ever encountered that was tripping a GFCI failed a megger test from one of the lines to equipment ground. GFCI was just doing what it is supposed to do. Most of them I have had owner or even appliance repairman try to tell me that GFCI was bad and needed replaced or even removed. I usually have to do some troubleshooting and show the appliance repair guy why it is tripping the GFCI. Defrost heaters like to mess with them but are only in circuit when timer calls for them so they don't always trip when service guy is there. Megger from neutral to EGC on the cord cap will still tell you there is a problem somewhere.

 

[Riograndeelectric]

Every refrigerator or freezer I have ever encountered that was tripping a GFCI failed a megger test from one of the lines to equipment ground. GFCI was just doing what it is supposed to do. Most of them I have had owner or even appliance repairman try to tell me that GFCI was bad and needed replaced or even removed. I usually have to do some troubleshooting and show the appliance repair guy why it is tripping the GFCI. Defrost heaters like to mess with them but are only in circuit when timer calls for them so they don't always trip when service guy is there. Megger from neutral to EGC on the cord cap will still tell you there is a problem somewhere.

could this not harm the compressor and fan coils ?

I am not familair with the in and outs of useing a megger

 

[jmellc]

Every refrigerator or freezer I have ever encountered that was tripping a GFCI failed a megger test from one of the lines to equipment ground. GFCI was just doing what it is supposed to do. Most of them I have had owner or even appliance repairman try to tell me that GFCI was bad and needed replaced or even removed. I usually have to do some troubleshooting and show the appliance repair guy why it is tripping the GFCI. Defrost heaters like to mess with them but are only in circuit when timer calls for them so they don't always trip when service guy is there. Megger from neutral to EGC on the cord cap will still tell you there is a problem somewhere.

I only saw that problem on GFCI receptacles, not breakers. I didn't have a megger, but I metered neutral/EGC & read no contact on them. Usually too, it was an older appliance, not a new one.

 

[kwired]

could this not harm the compressor and fan coils ?

I am not familair with the in and outs of useing a megger

Absolutely not. Only thing would be some newer refrigerator that may have electronics. A standard fridge with just motors, coils, dry contact switches will take a high potential test without any problem.

megger is very useful tool for finding cause of so called 'nuisance' tripping GFCI's

 

[jmellc]

What is the cost of a megger these days?

Why would an appliance trip the receptacle but not the breaker? I have never had an appliance trip a GFCI breaker, but often a receptacle. The projector I mentioned was the only nuisance tripping I saw on a GFCI breaker.

 

[Riograndeelectric]

Absolutely not. Only thing would be some newer refrigerator that may have electronics. A standard fridge with just motors, coils, dry contact switches will take a high potential test without any problem.

megger is very useful tool for finding cause of so called 'nuisance' tripping GFCI's

can you direct me to either a website or a book that teaches how to use Meggers.
I have been in the field for 30 year and have never used a megger. I believe it is time for me to learn.


I am interested in Buying a Megger however it is confusing to me as the models start out cheap and then work there way up in higher prices


Thank. Cameron

 

[George Stolz]

http://mercedeelectric.com/Documents/Megger-A_Stich_in_Time.pdf

I'd recommend a Fluke 1507 if you're looking, Cameron.

 

[kwired]

can you direct me to either a website or a book that teaches how to use Meggers.
I have been in the field for 30 year and have never used a megger. I believe it is time for me to learn.


I am interested in Buying a Megger however it is confusing to me as the models start out cheap and then work there way up in higher prices


Thank. Cameron

Depends on what you want to use it for. I have a cheap one. It works fine for pass/fail testing. If you want to use it for PM records a more expensive one as well as some training on what you should be looking for are more important.

For simple pass/fail tests it is no different than using a regular ohmmeter other than that you are putting out a higher test voltage. You have to be careful what you apply the test voltage to that may not survive the test.

Nothing wrong with testing with 1000 volts from a motor lead to the motor frame to test motor windings for ground faults. However you may not want to apply 1000 volts to leads that are also connected to a VFD. But just like checking resistance of anything else you need to isolate what you are checking or you will not necessarily get the result you are looking for.