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I'm trying to understand a bit about nuisance-tripping, and I'm wondering if anyone here has some insight.

I know (or think I know) that a Class A GFCI breaker should trip when there is a 6mA ground current (fault). I've also read that an AFCI breaker will generally trip when there is a 30mA ground current.

So my question is: are nuisance trips more likely on a GFCI due to that lower threshold (6mA), compared to AFCI (30mA)?

I apologize if my terminology isn't correct. I think I know what I'm asking, but... maybe not.

People seem to indicate that you should never use GFCI protection on your refrigerator due to the possibility of nuisance trips. But AFCI protection is required. I'm assuming the AFCI is less likely to nuisance-trip, and maybe this 6mA-to-30mA comparison explains why? The 30mA is low enough to mitigate fire risk, but high enough that most nuisance trips are avoided? (Whereas with a GFCI, the 6mA threshold is low enough to mitigate most risk of shock injury, but makes it more susceptible to nuisance trips?)

PhilPDX
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    Are you sure you aren't using an AFCI+GFCI combo breaker? AFCIs **are not** GFCIs with a different threshold. They work on a completely different principle. It's like "my car needs 92 octane gas but my brake fluid is 13 octane"......those things don't even... – Harper - Reinstate Monica Dec 31 '16 at 06:47
  • Not a dual-function breaker. AFCI breakers will trip if a ground-fault condition exists. (See, for example, the installation or troubleshooting instructions for an AFCI breaker.) My question is whether the higher threshold, compared to GFCIs, makes them less prone to nuisance tripping. – PhilPDX Dec 31 '16 at 22:47
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    Just found a similar question/topic here: https://diy.stackexchange.com/questions/102857/why-arent-gfci-and-afci-breakers-combined-or-used-together – PhilPDX Dec 31 '16 at 22:47
  • It depends on the type of load. AFCI breakers are not so good with variable speed motors like some kitchen appliances and exercise equipment another problem is with light dimmers and fluorescent lighting (normally with heavy loads +8 amps from my experience). I hope this information is helpful. – Ed Beal Jan 01 '17 at 01:29

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