According to a Siemens customer service. He checked his stock too and it's like that, and it was supposed to be normal. Is it really normal to have the spring clip and bus bar stab only having electrical contacts at the bottom? He wrote: "I have checked older GFCI 20amp 2 pole breaker that has same structure that you show & fits the same as your photos indicate. The surface contact of the breaker contacts to the load center stabs seems to be sufficient & has not changed and there have been no reports of failures."

In 1998 and 2010. Siemens QP were recalled due to one reported failure. So do they have to expect smoke and fire before it is considered as one report? Does anyone who have accessed to more knowledgeable Siemens engineers please ask them about this. Harper? Thanks.


This is a more scientific test. I used a feeler gauge blade and inserted the thinnest (size 0.0015") in between the bus bar and spring clip:


You can see only the contacts at the bottom of the spring clips and bus bar are connected. This is the same in all sides. Do you still agree that there is no problem? This can cause arcing, heat, burning, and fire. I think Siemens made a mistake. Their regular QP breakers fit perfectly (You can't insert any blade in any part).

How do I take this to the attention of Siemens? Their customers service said the breaker is a listed as compatible with the enclosure based on the literature but actual examination didn't support it.

  • Can you make measurements with calipers or a mm ruler on the spacing of the two sides of the breakers? Is the problem with the GFCI breaker that the spacing is wrong or is it that the gaps in the contacts for electrical contact are too large? Why do the GFCI breakers have the narrow slots on the face? Nov 17, 2018 at 13:08
  • It's narrow at bottom because when you insert it.. it gets wider. But the problem is the bus bar is bit thinner by maybe 1mm so when you insert it all the way. It still doesn't make full contact with the top sides. see picture.. imagizer.imageshack.com/v2/1024x768q90/921/9r36c6.jpg so what happens is there is gap at top to mid where you can insert 2 sheets of paper... like this illustration. imagizer.imageshack.com/v2/640x480q90/922/5ja03X.jpg maybe logic of Siemens is that there is enough area below for full electrical contact?? What do you guys think? All my 6 breakers same
    – Samzun
    Nov 17, 2018 at 14:31
  • For the regular Siemens QP breaker, notice the spring clips are narrower and perfect fit to the Siemens PL Load center... imagizer.imageshack.com/v2/1024x768q90/924/5MwhrQ.jpg The Siemens GFCI 2-pole breakers in the earlier image have wider spring clips spacing. If anyone can talk with Siemens Technical, kindly ask why.
    – Samzun
    Nov 17, 2018 at 14:47
  • Paging @ThreePhaseEel ... Nov 17, 2018 at 18:32
  • In this picture.. imageshack.com/a/img923/3739/8T1i1g.jpg you can see all sides of the spring clips of the Siemens GFCI breaker can be inserted with paper (the right breaker is a regular Siemens QP breaker where you can't insert any paper in between the contacts). In the GFCI breaker, the contacts are at least half of the spring clips only.. but then if you see this picture of comparison between Siemens GFCI and GE breaker, imagizer.imageshack.us/a/img921/5959/1jAoAA.jpg you can see the GE breaker only has small contact area equal to half the Siemens GFCI.. so it may work?
    – Samzun
    Nov 18, 2018 at 0:35

1 Answer 1


@samzun - very frustrating, it seems like you're doing your homework and still you have this problem. It's very good that you caught it though.

I can only see three possibilities:

  1. Someone at Siemens made a mistake confirming compatibility of this breaker. I do not believe this to be the case, but Siemen's web site and literature are not really helpful. If this is the case, I'd expect Siemens to provide the correct breaker.
  2. The breaker is defective. (Since other breakers fit, I doubt the panel bus is defective.) Again I'd expect a warranty replacement either from the retailer or the manufacturer.
  3. The breaker is a counterfeit. You might get a refund from the retailer, but I'd bring it to Siemens attention. Siemens and other manufacturers are very interested in stopping counterfeiters. See this document from Siemens: Counterfeit Circuit Breakers: A Growing Threat

If I can make a suggestion, in this and other questions, you are struggling quite a bit working with your panel bus. It might make more sense to use DIN rail mountable breakers which are commonly used in Europe. There's no bus with this system. This seems to me a much easier way to retrofit GFCI protection with your panel. For example look at the Eaton QPGF2030 or QPHGF2030 breakers.

  • Breaker is not defective nor counterfeit. I think Siemens may make it that way, the logic being there is still large electrical contact at half middle to bottom. See above comment to Jim Stewart, the Bus bar is thinner by maybe 1mm.. because if it's thicker.. then it can make full contact.. see pictures.. imagizer.imageshack.com/v2/1024x768q90/921/9r36c6.jpg and imagizer.imageshack.com/v2/640x480q90/922/5ja03X.jpg In my country, GE breaker has very tiny electrical contact, so I guess even if one third make contact, it is as good as full and won't create arcing, heating etc.?
    – Samzun
    Nov 17, 2018 at 14:41
  • 1
    @Samzun - I just don't think it's worth the risk, the reduced contact area but more importantly the looseness is too risky. Nov 17, 2018 at 18:22
  • looseness is not problem, it holds ok.. look at these 3 comparison picture between the Siemens GFCI, Siemens regular QP breaker and GE (General Electrical) 60A. imageshack.com/a/img921/5959/1jAoAA.jpg Look at the spring clips of the GE, it's much smaller, almost 1/3 that of the Siemens GFCI. My country all use GE because of the small contact area that is compatible with any locally made panel. Therefore if GE can make their 60A use small contact area, that means it's accepted, hence maybe Siemens think even if the Seimens GFCI breaker has 1/3 contact area, it still works. What u think
    – Samzun
    Nov 17, 2018 at 22:38
  • 1
    It's just outside my comfort zone to make a guess based on your description, what if I guess wrong?? Nov 17, 2018 at 22:44
  • In the panel actual list of compatible breakers.. the QPF is listed.. see the blue arrow in imageshack.com/a/img921/7649/vRblMW.jpg Also I wonder if the Siemens GFCI are only intended for use in the spa enclosure.. see imageshack.com/a/img924/8481/BWPEjh.jpg do you think it's bus bar is bigger? I can't compare between it based on picture and the my actual. And I don't want to spend another $100 just to buy the spa enclosure and check the bus bar size. Does it make sense Siemens GFCI are not intended to use for any normal home panel but only for spa?
    – Samzun
    Nov 17, 2018 at 23:03

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