Siemens GFCI breakers not compatible with Siemens panel?

[tersh]

Does anyone own any Siemens 2-pole GFCI? When installed on supposedly compatible Siemens panel or load center like the Siemens P1224B1100CU

There is a gap between the bus bar stab and spring clip where you can easily insert feeler gauge (after installation), and only the bottom has electrical contacts. Someone told me there should be no gap in compatible breaker and panel so there is no arcing, melting, heating and burning.

Kindly look at your 2-pole Siemens GFCI and panel to see if such gaps are normal. Note when I tried the Siemens regular QP breaker, there is no gap. Thanks.​

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[mopowr steve]

What ever compelled you to even look into this?

 

[tersh]

Because someone told me never to mix and match North American panels and breakers to avoid arcing, melting, heating, burning, and fire. So I make sure I buy only Siemens breaker and panel. But when I look at the spring clips and bus bar stab carefully of the Siemens QF230A and Siemens P1224B1100CU load center panel. There is gap and electrical contact only at bottom. But if you use the Siemens QP regular breaker. There is no gap and the contact is perfectly flat.

 

[jaggedben]

The breaker is listed for that panel. You don't need to nitpick their manufacturing or design. For all you know there is absolutely nothing wrong with what you've discovered.

 

[tersh]

The breaker is listed for that panel. You don't need to nitpick their manufacturing or design. For all you know there is absolutely nothing wrong with what you've discovered.

But before I bought them. Siemens told me they were supposed to be compatible.

How do you know the breaker is not listed for that panel?

 

[tersh]

But before I bought them. Siemens told me they were supposed to be compatible.

How do you know the breaker is not listed for that panel?

Here the actual panel listed the QF260A which is type QPF as compatible. And Siemens admitted they were compatible.

So if the gap is also present in all Siemens GFCI breakers and their listed panels. Is it still acceptable or must Siemens recall them?

 

[mopowr steve]

Call Siemens and ask to bring this issue up with their engineers, maybe you found something they may not be aware of durring manufacture.

 

[jaggedben]

Here the actual panel listed the QF260A which is type QPF as compatible. And Siemens admitted they were compatible.

So if the gap is also present in all Siemens GFCI breakers and their listed panels. Is it still acceptable or must Siemens recall them?

Where does it say there's not supposed to be a gap? What UL standard does the gap violate? Do you have any technical engineering knowledge about what kind of gap is acceptable per the listing standards for plug-on breakers? Have you observed a pattern of poor contact performance among the breakers with the gaps?

 

[tersh]

Where does it say there's not supposed to be a gap? What UL standard does the gap violate? Do you have any technical engineering knowledge about what kind of gap is acceptable per the listing standards for plug-on breakers? Have you observed a pattern of poor contact performance among the breakers with the gaps?

If you will use the regular Siemens Q230 QP breaker https://www.amazon.com/Q230-30-Amp-..._rd_t=40701&psc=1&refRID=Z5H1FVSZVW15KYA27Y2Q

There is absolutely no gap. The spring clips and bus bar stab are flat and you can't insert any paper. Someone told me proper match should have no gaps with only electrical contacts at bottom.

Anyway Siemens customer support emailed me:

"I had a meeting with engineering on this yesterday. They would like to have you return the QF260A & QF230A for better analysis in the lab. In exchange, we can ship you replacements to install. Please advise a good ship to address for these breakers."

I told them to buy the Siemens QF260A at amazon and Siemens QF230A at GFI warehouse to get same samples as me. Also they can easily check their units if there is a gap and it's normal. I just want words from their engineering that the gaps are normal before I use them.

 

[jaggedben]

... Someone told me proper match should have no gaps with only electrical contacts at bottom.

...

Who?

 

[tersh]

Who?

I read someone (anonoymous) who wrote in the internet and said:

"The magic snap is not magic. Contact blades are not flat.

One thing you will notice about US breakers in matching panels is that they "Snap" in with a definite resounding snap. And when you try to remove them, the initial force needed to pull them out the first 0.1mm is considerably greater than the force needed to pull them the rest of the way. That's because the bus bar in the service panel actually has a little "nub" shaped into it, of a specific shape. That shape engages matching curves on the breaker's spring clip. It works like a detent, creating the snap. However the good contact also creates a lot of mating surface area. As such, it runs at sane temperatures during high current flow, which is why UL approves it. Every panel manufacturer uses a different shape of bus bar, requiring different shaping on the breaker's spring clip. They are different because of patents. Each manufacturer has patented their shape, because they think it outperforms their competitor's shape (and avoids violating their competitor's patents). Eventually patents expire, such as Square D's QO (queue oh) patent expired, permitting Murray/Siemens to manufacture its QD (queue dee) breakers for QO panels. Still, Siemens is unable to make breakers that fit both Murray and QO panels, because they are still different. They are locked into the old designs because new breakers need to fit old and new panels alike. So when you use an alien breaker, the clips and nubs don't mate as intended by the two manufacturers, and this is not an accident, it's by design. They are not trying to keep you from using alien breakers, they are (were) trying to keep from being sued for patent infringement. Anyway, you end up with the clips only mating at 2-4 points instead of flat surface contact, and point contact like that is only good for a couple of amps before it starts melting, opening, arcing and burning."

After I read it. I immediately bought the Siemens panel after Siemens confirmed they were compatible with their GFCIs. I also bought an extra Siemens Q230 QP breaker for testing and it matched perfectly. But not the Siemens GFCIs. In the following the spring clips differ.

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All 6 pcs of GFCIs have the same spring clips (on the left) that seems to require thicker bus bar.
I requested Siemens to transfer the spring clips from their QP Q230 to the GFCI for perfect fit. Then I'll send them all my 6 pcs for replacement.

 

[growler]

Anyway Siemens customer support emailed me:

"I had a meeting with engineering on this yesterday. They would like to have you return the QF260A & QF230A for better analysis in the lab. In exchange, we can ship you replacements to install. Please advise a good ship to address for these breakers."

I told them to buy the Siemens QF260A at amazon and Siemens QF230A at GFI warehouse to get same samples as me. Also they can easily check their units if there is a gap and it's normal. I just want words from their engineering that the gaps are normal before I use them.

There is always a chance that your Siemens breaker purchased from Amazon was not really manufactured by Siemens.

Wouldn't be the first time that a knock-off made it into the supply chain.

 

[hbiss]

There is always a chance that your Siemens breaker purchased from Amazon was not really manufactured by Siemens.

Wouldn't be the first time that a knock-off made it into the supply chain.

I agree. I don't think the issue is incompatibility but either a defective product or a counterfeit. You can tell that from the last picture. Would be interested in knowing what Siemans has to say after seeing it.

-Hal

 

[growler]

I agree. I don't think the issue is incompatibility but either a defective product or a counterfeit. You can tell that from the last picture. Would be interested in knowing what Siemans has to say after seeing it.

-Hal

It doesn't sound like the OP wishes to send his breaker to Siemens for evaluation/testing .

As you say it could also be poor quality control (defective manufacture ) but I think they will need to have the breaker to make a determination.

 

[tersh]

I agree. I don't think the issue is incompatibility but either a defective product or a counterfeit. You can tell that from the last picture. Would be interested in knowing what Siemans has to say after seeing it.

-Hal

What if those were genuine Siemens GFCIs? The customer service told me he himself saw the same gaps when he tested his 2-pole. This was why I didn't send the 6 breakers back because it would incur huge shipping cost back and forth when they can easily test their own samples. If they can't insert any feeler gauge, then that's the time I'd consider my items as counterfeit.

I'm guessing it's genuine. In 1998. They recalled 144,000 Siemens GFCI because of some issues. Maybe time to recall all present GFCIs to replace the spring clips.

https://www.cpsc.gov/Recalls/1998/c...nce-recall-of-gfci-circuit-breakers-used-with

They also did some recalls in 2010

https://www.cpsc.gov/Recalls/2010/Siemens-Recalls-Circuit-Breakers-Due-to-Fire-Hazard/

If I spread the images in my original message via youtube and social media showing there is gap between the Siemens GFCI and Siemens panel and compare it to say Square D that doesn't have gaps. Perhaps it can persuade them to recall them?

 

[jaggedben]

So contact Siemens and if it's a real issue then they should issue a recall.

I think you're engaging in a fair amount of speculation with no definite substance.

 

[tersh]

So contact Siemens and if it's a real issue then they should issue a recall.

I think you're engaging in a fair amount of speculation with no definite substance.

I already contacted them days ago. And waiting for their tests and decisions. If they would say the gap is normal. Then that's the time I'll connect the 6 Siemens GFCI to the subpanel. I'm just asking if anyone here owns a Siemens GFCI and noticed the gap too.

 

[hbiss]

You seem to be making a lot of assertions based on your and people on the internet's opinions. Instead of being a crusader, why don't you let Siemens do their job. If they are willing to replace whatever you send back, be assured that what they send you as replacements are genuine and not defective.

If I spread the images in my original message via youtube and social media showing there is gap between the Siemens GFCI and Siemens panel and compare it to say Square D that doesn't have gaps. Perhaps it can persuade them to recall them?

You would be just another crackpot.

-Hal

 

[jaggedben]

Maybe the gap is out of spec and maybe it isn't. Unless there's something enlightening in a UL standard, then Siemens tolerances are probably proprietary, and it's unlikely we in this forum have any light to shed on it.

 

[tersh]

Maybe the gap is out of spec and maybe it isn't. Unless there's something enlightening in a UL standard, then Siemens tolerances are probably proprietary, and it's unlikely we in this forum have any light to shed on it.

I'll wait for Siemens engineering feedback about it and share with you what they would tell me.

But I'm doing my own calculations

to measure the electrical contact area between the bus bar stab and spring clip​

An electrical engineer told me:"Compute the area as you would any rectangle. Remember that there is still a gap for a short distance below the edge of the feeler gauge.I've never investigated that. But it would seem the contact area would have to be no less than the cross sectional area of the maximum wire size for the breaker... and probably a little more because of the added resistance due to the pressure contact versus the continuous metal of a wire."

from bottom view, the width of the spring clip is 7mm.

This is the front showing only 2mm of electrical contact between the stab and spring clip.
so the area is 7mmx2mm = 14mm
Now in the AWG size and cross section conversion...
https://www.rapidtables.com/calc/wire/awg-to-mm.html
14mm corresponds to AWG 6. And in this amperage and insulation temperature table... https://images.homedepot-static.com/catalog/pdfImages/a7/a767224b-82d0-41a6-a02f-316c94392ce1.pdf
You get 65A for the 75c column (75c because this is the terminal temperature rating of the breaker). And this is only for one side of spring clip. For 2 sides, the capacity is 65A x 2 = 130A!
So even with the partial electrical contact, there is already 130A.
What is wrong with my computations? I know we need to factor in the resistance of the pressure contacts, how do you do that?

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