Circuit Breaker teardown and defective Siemens latching mechanism

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tersh

Senior Member
Location
new york
All observed and experienced correctly, the cover aligns and keeps things from flying out. Some brands are better at it then others, but even the cutler hammer breakers will have parts pop out at times.



The part you have traced out in red was aligned, but, that you mentioned it its possible the common trip was not aligned as well as I though it was.

Hmm.. when I have time tomorrow. I'll open the 20A just like you did, or with smaller opening just to trip the bimetal.

Hope you are right, that the old common trip piece had flaw. Because if I'm right. Counterfeit GE breakers may be abound in the country (hundreds of thousands are sold here as it's the only Plug in and bolt on breakers we use).



I'd think both poles would be counterfeit if so. All the parts are assembled at a single factory.


Only way to know is to test.


Another possibility is a manufacturing defect. I've had GE breakers broken right out of the box here in the US.



Regarding counterfeits, only way to know is a certification from the manufacturer. Some counterfeits are obvious as day, others are indistinguishable from the real thing. Especially when a US company opens up a factory in China building parts to their spec. Then the contract runs out and everything is left behind- only for them to start making counterfeit good using the same molds, spec, logos, intellectual property, ect as a reputable manufacturer.
 

tersh

Senior Member
Location
new york
IMHO, I think we are both right.


If the catch is aligned, the black common trip is aligned too because there is no other ways for it to move. Unless it can move forward?

When you remove the common handle, and turn the other side OFF. Can't you just see if the white common trip lever moved? Because if it can't move, then it shouldn't affect the other side making the black thing lean forward, isn't it?
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
If the catch is aligned, the black common trip is aligned too because there is no other ways for it to move. Unless it can move forward?

When you remove the common handle, and turn the other side OFF. Can't you just see if the white common trip lever moved? Because if it can't move, then it shouldn't affect the other side making the black thing lean forward, isn't it?

It moved slightly. And the common trip tilted forward just a hair.
 

tersh

Senior Member
Location
new york
HwoCI9l.jpg


It moved slightly. And the common trip tilted forward just a hair.

First. About the GE breakers. Since GE Singapore still make those versions of breakers supplied to the Phils. Is it possible they are using the same old parts but the defect was already fixed so in my 2010 versions with same old common trip. There is no more leaning forward of the black common trip piece (maybe the enclosure spacing was fixed already)? Was your made in the 1990s?

Btw.. I forget to ask you something about the GE panel above. I have never seen even one of these in the entire country because we don't have it in stock anywhere (remember we just used locally made panel).

Since last year I wanted to know how thick was the bus bar stubs of the GE panel, because I wanted to know if the Siemens panel bus bar stub was a bit thicker or the same.

The locally made bus bar stubs were a bit thinner than the Siemens panel bus bar stubs, so I wondered if the thickness was made to match the original GE panels, what do you think?

I was thinking of all of them last year when I wondering why there was a gap in between the spring clips and bus bar stubs of the Siemens panel and GFCI breakers. But Siemens told me it was no problem (that's why it took me months before I finally had the panel installed).
pWWk0Y.jpg
 

kwired

Electron manager
Location
NE Nebraska


First. About the GE breakers. Since GE Singapore still make those versions of breakers supplied to the Phils. Is it possible they are using the same old parts but the defect was already fixed so in my 2010 versions with same old common trip. There is no more leaning forward of the black common trip piece (maybe the enclosure spacing was fixed already)? Was your made in the 1990s?

Btw.. I forget to ask you something about the GE panel above. I have never seen even one of these in the entire country because we don't have it in stock anywhere (remember we just used locally made panel).

Since last year I wanted to know how thick was the bus bar stubs of the GE panel, because I wanted to know if the Siemens panel bus bar stub was a bit thicker or the same.

The locally made bus bar stubs were a bit thinner than the Siemens panel bus bar stubs, so I wondered if the thickness was made to match the original GE panels, what do you think?

I was thinking of all of them last year when I wondering why there was a gap in between the spring clips and bus bar stubs of the Siemens panel and GFCI breakers. But Siemens told me it was no problem (that's why it took me months before I finally had the panel installed).
pWWk0Y.jpg
Keep in mind the Siemens breaker was tested and listed to go into Siemens panels, and the same for GE. You were installing it in something other than what it was tested for.

I don't know why the contact point is apparently tapered but must be some design purpose for it and the amount of contact surface that does occur (in a panel it was tested for) is supposedly sufficient to meet the needs.
 

tersh

Senior Member
Location
new york
Keep in mind the Siemens breaker was tested and listed to go into Siemens panels, and the same for GE. You were installing it in something other than what it was tested for.

I don't know why the contact point is apparently tapered but must be some design purpose for it and the amount of contact surface that does occur (in a panel it was tested for) is supposedly sufficient to meet the needs.

The Siemens P1224B1100CU Load Center listed the QPF breakers (GFCI breakers) as compatible and even Siemens Engineering told me they were made for each other. However. Something puzzled me last year and still now. The reqular Siemens QP breakers have smaller clip distance that totally bite the Siemens bus bar stubs such that you couldn't insert any feeler into it. But the Siemens GFCI breakers have wider gaps. When I asked Siemens about this. They didn't answer exactly why just saying the panel and GFCI breakers are listed (hence I'm really using them where they tested them to be listed).

1jAoAA.jpg
 

kwired

Electron manager
Location
NE Nebraska
The Siemens P1224B1100CU Load Center listed the QPF breakers (GFCI breakers) as compatible and even Siemens Engineering told me they were made for each other. However. Something puzzled me last year and still now. The reqular Siemens QP breakers have smaller clip distance that totally bite the Siemens bus bar stubs such that you couldn't insert any feeler into it. But the Siemens GFCI breakers have wider gaps. When I asked Siemens about this. They didn't answer exactly why just saying the panel and GFCI breakers are listed (hence I'm really using them where they tested them to be listed).

1jAoAA.jpg

I don't use many Siemens breakers so won't claim to know everything about them, but is it possible your GFCI is a newer production run than your other Siemens breakers and is using different pieces and is possible newer non GFCI might be using same parts?
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician


First. About the GE breakers. Since GE Singapore still make those versions of breakers supplied to the Phils. Is it possible they are using the same old parts but the defect was already fixed so in my 2010 versions with same old common trip. There is no more leaning forward of the black common trip piece (maybe the enclosure spacing was fixed already)? Was your made in the 1990s?



Keep in mind your breaker is 100amps, not 20. The spring is much stronger and the parts are heavier so that might be enough to get it to break through the snag.


Yes, mine are before 1990- from the 80s in fact.



Btw.. I forget to ask you something about the GE panel above. I have never seen even one of these in the entire country because we don't have it in stock anywhere (remember we just used locally made panel).

Because of cost correct?

Since last year I wanted to know how thick was the bus bar stubs of the GE panel, because I wanted to know if the Siemens panel bus bar stub was a bit thicker or the same.

The locally made bus bar stubs were a bit thinner than the Siemens panel bus bar stubs, so I wondered if the thickness was made to match the original GE panels, what do you think?

I was thinking of all of them last year when I wondering why there was a gap in between the spring clips and bus bar stubs of the Siemens panel and GFCI breakers. But Siemens told me it was no problem (that's why it took me months before I finally had the panel installed).


The GE bus stabs are thicker from other US made panels, and I'd say thicker then your local panels but can't say for sure.

Out of all the panel brands out there, GE has the fewest burn ups in the plug on line. Fewer then QO if you ask me.
 

tersh

Senior Member
Location
new york
Square D QO and Homeline 15-30 amp breakers can take 2 wires of the same size.


While your breaker setup above is an NEC violation, I doubt its actually dangerous as long as both wires are copper or both aluminum at the same time. Ie, do not mix metals. I've TONS of double tapped breakers in residential without issue.

Finally the torque screwdrivers have arrived (along with the dependable alumiconn). And it's very good. No more concerned whether the electrican turn breaker lugs too tight or too loose. When the screwdriver reached the desired torque. It slips. But for those expert electricians who are used to it. I think you can get good estimate of 25 lb-in and just like basketball throw the ball in the basket dead center.

4Xp4IW.jpg




9tEgY6.jpg



My question is this. If there are two wires inserted in one breaker terminal. What must be the torque for say two AWG 10 wires? Must it be 20 in-lbs or 25 in-lbs. What do you think?

Getting the desired torque is very important to be sure the two wires and terminal lugs should have conduction at least equal to the wire original area.

2fwacN.jpg
 

tersh

Senior Member
Location
new york
Use a screw driver to bend the case upwards trying to get it to crack at the 1/3 point- all you need is a way to expose the bimetal to get it to trip.



Honestly, I have not. But I guess it could be replicated doing the same thing and whacking the breaker into your palm to get it to trip.






Well, you may be on to something. I had not thought of the covering playing that big a role in the common trip and maybe it does.

I'd try the experiment with a 20 making it trip and then measuring the continuity. Hopefully you are right Tersh.

I just did the experiment above. I drilled a tiny hole just a few millimeter away from the bimetal strip (a blank space) so inserting a paper clip would instantly trip the breaker. See this video:


I removed the handle tie. Put the other in OFF position, and tripped the other in On position with paper clip. It tripped.

Our latest batch of breakers from Singapore may have that defect already sorted out. The sample you had in 1980 was of different era so it may have that defect.

The implication of all is that the breakers bought by this American living in the province would be really counterfeit. Late last year I wrote him in his electrical blog page and he replied there the following. See: https://myphilippinelife.com/philippine-electrical-wiring/

"

Jim, First of all, we are not experts so take our reports with this in mind. Remember that those GE breakers are linked so that if either side trips, they both trip. We feel quite certain that our breakers are genuine. We also can confirm that one side of our GE breakers had NO overload protection by itself. Of course we had clipped the links between the two sections of the breakers. We thought we were so clever! The engineering of breakers is way beyond our pay grade, but I feel sure that had we not clipped the link, the breaker would have tripped when the circuit was shorted out. We see your point that both sides should logically include over current protection but I won’t second guess GE. We already learned that it’s not a good idea. Since we reconnected the breakers, we have never had a tripped circuit. Regarding grounding, as we explained that we used our house rebar as our ground.
"

He thought the common handle tie was what made both trip. In fact our electrical supplier thought of that too. And I thought it was all that. Unless you mentioned about common internal trip. What do make of all this? His product is also made in Singapore. Or fake product with label only made in Singapore? Or did he somehow got the 1980s version like yours? unlikely since it's made in Singapore and not Dominican Republic.

ViTc31.jpg
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
My take is that the torque required is related to the diameter of the wire (flatter requires/tolerates more torque). So I would go by wire size regardless of number.

Sent from my XT1585 using Tapatalk
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
Did you try it a few times? And checked for no continuity with a meter? If it doesn't jam after a few tries I'd say your all good. Its possible the issue was taken care of with latter batches. Heck maybe mine was jamming up due to the case being half removed. Either way your test proves that it may not be an issue after all.


I can only guess why the guys breaker did not trip. Maybe counterfiet. Maybe jamming. Maybe defect. Hard to say but I certainly wish I was there to examine that failed breaker.
 

tersh

Senior Member
Location
new york
Did you try it a few times? And checked for no continuity with a meter? If it doesn't jam after a few tries I'd say your all good. Its possible the issue was taken care of with latter batches. Heck maybe mine was jamming up due to the case being half removed. Either way your test proves that it may not be an issue after all.


I can only guess why the guys breaker did not trip. Maybe counterfiet. Maybe jamming. Maybe defect. Hard to say but I certainly wish I was there to examine that failed breaker.

Yes I tried it many times since it is very easy to trip it by just inserting the clip which moves the bimetalic strip and trip it (this instantly cut the continuity in the multimeter test). So there is no more problems.

Whatever. Do you have any sample of a counterfeit breaker? How does the inside look like? Maybe the bimetallic strip is just piece of metal that is not bi metal but just one piece? Or are counterfeit breakers components the same ones from the plants and only assembled at basement of the counterfeiters or do they make separate springs, etc. for the components?

Also please don't miss message #150 about inserting 2 wires inside terminal lugs of breakers. Why did you see it in many residentials? Don't they use wire nut or alumiconn instead? In message #150, I was asking what torque must be used for two AWG 10 inserted:

2fwacN.jpg


GoldDigger
My take is that the torque required is related to the diameter of the wire (flatter requires/tolerates more torque). So I would go by wire size regardless of number.​


Why would AWG 6 be flatter than AWG 10? AWG 6 is thicker, why is it flatter? maybe because bigger hence flatter at small section? About the two AWG 10. Imagine there were on top of each other and the torque is just 20 lb-in. If they stay on top of each other, the area may not reach the minimum required hence bigger torque value can make sure they are pressed or squished for more contact. Isn't it?
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
No samples sadly. :(


In residential I saw 2 wires going to a breaker only rated for one all the time. No issue and if the wires are the same size I don't see that much of a problem.
 

tersh

Senior Member
Location
new york
No samples sadly. :(


In residential I saw 2 wires going to a breaker only rated for one all the time. No issue and if the wires are the same size I don't see that much of a problem.

You mean no matter how they are torqued. The two wires can always touched between themselves and the lugs and it will always be at least the area of the wires? I'm concerned if there are scenario for few contact points only enough to heat it and cause glowing connections.

Also if you have a caliper and a GE panel. When you have time, kindly measure how many millimeters is the bus bar stubs where the GE breaker plug in spring clips are biting. Because if our locally made bus bar are thinner. Then at least I know all our breakers were not really listed for the panels. But since there are few bus bar burn. I think the bites of the breakers themselves are versatile? In homes this may not be much concern because of low loads. But in office building. It may be of more concern. Fortunately, my office building has bolt-on breakers, so no issues with bus bar thickness.

Knowing the GE panel bus bar stub thickness will also finally made me decide whether to replace the entire plug in panel at house rather than just buying many new plug-in 2 pole breakers to replace the dozens of 1-pole breaker installed where only one can trip because of lack of internal tripping mechanism.

By the way. Why is din rail MCB now allowed in the US. They are really much cuter and nicer and more compact.
 

GoldDigger

Moderator
Staff member
Location
Placerville, CA, USA
Occupation
Retired PV System Designer
Yes I tried it many times since it is very easy to trip it by just inserting the clip which moves the bimetalic strip and trip it (this instantly cut the continuity in the multimeter test). So there is no more problems.

Whatever. Do you have any sample of a counterfeit breaker? How does the inside look like? Maybe the bimetallic strip is just piece of metal that is not bi metal but just one piece? Or are counterfeit breakers components the same ones from the plants and only assembled at basement of the counterfeiters or do they make separate springs, etc. for the components?

Also please don't miss message #150 about inserting 2 wires inside terminal lugs of breakers. Why did you see it in many residentials? Don't they use wire nut or alumiconn instead? In message #150, I was asking what torque must be used for two AWG 10 inserted:

2fwacN.jpg




Why would AWG 6 be flatter than AWG 10? AWG 6 is thicker, why is it flatter? maybe because bigger hence flatter at small section? About the two AWG 10. Imagine there were on top of each other and the torque is just 20 lb-in. If they stay on top of each other, the area may not reach the minimum required hence bigger torque value can make sure they are pressed or squished for more contact. Isn't it?
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By "flatter" I mean still a circular cross section, but with a larger radius. To get the same contact pressure with a larger footprint area (under the screw point, against the deformed wire), requires a higher force.

Sent from my XT1585 using Tapatalk
 

tersh

Senior Member
Location
new york
Finally the torque screwdrivers have arrived (along with the dependable alumiconn). And it's very good. No more concerned whether the electrican turn breaker lugs too tight or too loose. When the screwdriver reached the desired torque. It slips. But for those expert electricians who are used to it. I think you can get good estimate of 25 lb-in and just like basketball throw the ball in the basket dead center.




9tEgY6.jpg



My question is this. If there are two wires inserted in one breaker terminal. What must be the torque for say two AWG 10 wires? Must it be 20 in-lbs or 25 in-lbs. What do you think?

Getting the desired torque is very important to be sure the two wires and terminal lugs should have conduction at least equal to the wire original area.


I finally let the electrician used the 10-50 in-lbs Torque screwdriver I received yesterday to all the breakers in the main panel and subpanel. The Siemens load center MBK100A breaker is the hardest to torque because of the 55 in-lb torque rating. The tool has only 50 in-lbs maximum torque.

YtWsRI.jpg




So far all breakers were under tightened, except for some 20 in-lb breakers that were tight already. Some were under tightened by 50% like the Siemens main breaker and the din rail MCB with recommended torque of 55 in-lbs and 30 in-lbs respectively.

The reasons most were under tightened are because we used screwdrivers with only small handle. When the electrician thought it was already hard, he stopped, not aware only half of the recommended torque was reached. The torque screwdriver with bigger handle can create the right torque. I guess US electricians all use big handle screwdrivers and can estimate the amount of torque already? Asian electricians can't estimate and it depends on what kinds of screw drivers were supplied to them by the contractors, engineers or owners.


In the Siemens main panel, the electrician was able to torque the right lugs well to reach the 50 in-lbs limit (when the torque setting was reached, the screwdriver slips instead of click sound, it is great design) but when tightening the left lugs. He couldn't reach 50 in-lb before the screws got so deformed the tool can no longer fit tight.

YZeC2E.jpg



So my three questions to mbrooke or others who can give tips to Asian electricians.

1. How can you know whether the hex bit is the right size for the lugs or any screws? It should perfect fit the lugs hole without any movement at all?
2. What is the biggest flat screw driver that can fit the Siemens MBK100A load center main panel perfectly?
3. Where to get an extra lug screw for the Siemens MBK100A? This is the product:

https://www.amazon.com/Siemens-MBK100A-100-Amp-Circuit-Ultimate/dp/B005D6DHQK

Thanks.
 

mbrooke

Batteries Included
Location
United States
Occupation
Technician
You mean no matter how they are torqued. The two wires can always touched between themselves and the lugs and it will always be at least the area of the wires? I'm concerned if there are scenario for few contact points only enough to heat it and cause glowing connections.


As long as they both go in parellel, I've seen no issues.

Also if you have a caliper and a GE panel. When you have time, kindly measure how many millimeters is the bus bar stubs where the GE breaker plug in spring clips are biting. Because if our locally made bus bar are thinner. Then at least I know all our breakers were not really listed for the panels. But since there are few bus bar burn. I think the bites of the breakers themselves are versatile? In homes this may not be much concern because of low loads. But in office building. It may be of more concern. Fortunately, my office building has bolt-on breakers, so no issues with bus bar thickness.

Knowing the GE panel bus bar stub thickness will also finally made me decide whether to replace the entire plug in panel at house rather than just buying many new plug-in 2 pole breakers to replace the dozens of 1-pole breaker installed where only one can trip because of lack of internal tripping mechanism.


I don't have any calipers with me, but from the looks of it your panel bausbars are thinner.


How old is your home panel and its breakers? If over 30 years old replacing it would not be a dumb move.


By the way. Why is din rail MCB now allowed in the US. They are really much cuter and nicer and more compact.


I still don't think they would be allowed. Jraef would know the full details, but IEC breakers in the US are only listed as supplementary over current devices or something to that effect. I may start a thread on that as I am just as curious as you...
 

romex jockey

Senior Member
Location
Vermont
Occupation
electrician
fascinating thread tersh.
:thumbsup:
i'm moved to find some calipers ,and throw them in my worktruck to assess all these breaker buss bars of different types.

If in fact they do differ, in that there is no 'buss bar' standrad for all manufactuers , then i'm curious as to how 'universal breakers' (we have Eaton and T&B) could possibly be listed to address the difference?

Further, if indeed so....what good would adhereing to tourqe specifications be for any installer?:?

As to the whole counterfiet breaker scenario , our trade rage (which are basically monthly advertisments for manufacturers) ran full page ads of electricians behind bars a while ago.:happysad:


The reality being they were thwarting internet sales for their domestic distributors , ironically who procured their materials from the very same 3rd world sources that produced a line of fakery...


~RJ~
 
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