Circuit Breaker teardown and defective Siemens latching mechanism

[tersh]

Even after having meeting with other local engineers. We still couldn't fathom the cause of this strange Siemens main panel latching anomaly.

First. I just made teardown of a Westinghouse breaker and became so familiar with all the mechanisms I can take all things apart and assemble the inside.





In this video. If I don't lock the on position by pushing it down, it won't lock.

https://www.youtube.com/watch?v=fTo2acI93XM

Here I locked it in position and it stays on. In the third attempt. I didn't push it in so it returned.

https://www.youtube.com/watch?v=tCqGNRzIMO0

Has anyone tried any Siemens main panel breaker used the PL series? Could it somehow be normal (or just tolerance issue)? Using the Westinghouse breaker teardown. I couldn't extrapolate what is wrong with the Siemens.

I couldn't return the item. It costs $45. And a new one cost $85 shipped. So I need to know if what could possibly be wrong with the Siemens. Doesn't it use a standard latching mechanism? Any illustration of what mechanism it could be using?

 

[LarryFine]

Methinks it's a simple case of mechanical wear.

 

[tersh]

Methinks it's a simple case of mechanical wear.

But it's brand new. Never been used. I couldn't return it because it has to be exchanged at a US address.

For normal circuit breaker. When it trips. You have to put it to OFF first to re-engage the lever next to the bi-metal or thermal magnetic strip. Then you turn it ON to engage the contacts. I have played with the teardown Westinghouse breaker and so familiar with it.

In the case of the brand new Siemens breaker. One has to press gently after it is in ON position before it stays ON.

Anyone has actually handled one of these? Isn't it normal?

 

[Dennis Alwon]

Sounds like a defective unit.

We have discover that many CH 200 amp main breakers will not either turn off the power or the handle will just flip back up without engaging the mechanism. We installs many of these in the 90's and now I have gone back to about 5 different jobs where we had to work on the service and discovered they were defective. CH started to cover the cost of the breaker but now has refused to do so. I think they have had a defective batch that never got caught because no one usually turns the main on and off again on install.

 

[tersh]

After teardown of the Westinghouse Breaker and handling it for a day at office during break removing the parts and putting them back again and again. It gave me courage to finally initiate teardown of the Siemens Load Center main circuit breaker (especially when no one can offer any clue what could be wrong with it and no teardown of it anywhere in the net).


I spent more than an hour in the evening removing the 4 mini-bolts manually so it won't damage the unit if drill is used. I found out the problem. First youtube video of the internal parts and illustrations:

It's just a typical circuit breaker internal components. Nothing unique. The source of the problem why you need to push it a bit more for the latching to be made is due to housing dimension tolerance. Compared to other breakers where the latching is made 75%. In the Siemens. It is 90% before the spring hatches it to make full contact. So slight housing misalignment need you to push it a bit more (and it is only in one of the breaker (remember it is two pole so has 2 separate unit). No problems with the bi-metallic strips or catch mechanism.

 

[GoldDigger]

Fascinating. Even if you cannot officially return for warranty replacement, I am sure there are engineers in the company who would love to take a look at that breaker.

 

[mbrooke]

Fascinating. Even if you cannot officially return for warranty replacement, I am sure there are engineers in the company who would love to take a look at that breaker.

They did that with a GFCI of mine, though it was Leviton.

 

[mbrooke]

After teardown of the Westinghouse Breaker and handling it for a day at office during break removing the parts and putting them back again and again. It gave me courage to finally initiate teardown of the Siemens Load Center main circuit breaker (especially when no one can offer any clue what could be wrong with it and no teardown of it anywhere in the net).


I spent more than an hour in the evening removing the 4 mini-bolts manually so it won't damage the unit if drill is used. I found out the problem. First youtube video of the internal parts and illustrations:

It's just a typical circuit breaker internal components. Nothing unique. The source of the problem why you need to push it a bit more for the latching to be made is due to housing dimension tolerance. Compared to other breakers where the latching is made 75%. In the Siemens. It is 90% before the spring hatches it to make full contact. So slight housing misalignment need you to push it a bit more (and it is only in one of the breaker (remember it is two pole so has 2 separate unit). No problems with the bi-metallic strips or catch mechanism.

You are smarter then I am, that is for sure. I think you've figured it out, and better then I could have despite tearing down many breakers...

 

[tersh]

You are smarter then I am, that is for sure. I think you've figured it out, and better then I could have despite tearing down many breakers...

You provided me all the references. And i dont come actual defects. If there is actual mechanical defects. Then i dont know either also there seems to be other designs with solenoids. I havent seen them and hope i wont as breakers are critical components and better left to the factories But in case you have seen teardown of GFCI breakers. Pls let me know. I dont want to be tempted to teardown a new one just to see how the compnents are put together or layout. Lol

 

[mbrooke]

You provided me all the references. And i dont come actual defects. If there is actual mechanical defects. Then i dont know either also there seems to be other designs with solenoids. I havent seen them and hope i wont as breakers are critical components and better left to the factories But in case you have seen teardown of GFCI breakers. Pls let me know. I dont want to be tempted to teardown a new one just to see how the compnents are put together or layout. Lol

Regular US breaker:

Old (trash) FPE breakers:

 

[mbrooke]

You provided me all the references. And i dont come actual defects. If there is actual mechanical defects. Then i dont know either also there seems to be other designs with solenoids. I havent seen them and hope i wont as breakers are critical components and better left to the factories But in case you have seen teardown of GFCI breakers. Pls let me know. I dont want to be tempted to teardown a new one just to see how the compnents are put together or layout. Lol

Sylvania Breaker

 

[mbrooke]

You provided me all the references. And i dont come actual defects. If there is actual mechanical defects. Then i dont know either also there seems to be other designs with solenoids. I havent seen them and hope i wont as breakers are critical components and better left to the factories But in case you have seen teardown of GFCI breakers. Pls let me know. I dont want to be tempted to teardown a new one just to see how the compnents are put together or layout. Lol

AFCI:

 

[mbrooke]

You provided me all the references. And i dont come actual defects. If there is actual mechanical defects. Then i dont know either also there seems to be other designs with solenoids. I havent seen them and hope i wont as breakers are critical components and better left to the factories But in case you have seen teardown of GFCI breakers. Pls let me know. I dont want to be tempted to teardown a new one just to see how the compnents are put together or layout. Lol

IEC breakers tend to have solenoids to help lower the magnetic trip threshold. At 230 volt line to ground its a good idea to have a quick disconnect time when a fault occurs.

Here is a QO GFCI:

 

[tersh]

IEC breakers tend to have solenoids to help lower the magnetic trip threshold. At 230 volt line to ground its a good idea to have a quick disconnect time when a fault occurs.

Here is a QO GFCI:

Thanks so much for the references esp the GFCI breakers. I have been looking for them the past 4 months. If you know how the Siemens Gfci looks inside. Pls share. I used to suspect if i had counterfeit gfci breakers. I heard there are several hundred thousand counterfeit breakers..i wonder if there are counterfeit gfci breakers too. Im tempted to fry open my 60A siemens breakers. Its being sold cheap at amazon compared to their 30A siemens gfci breakers. Also remember the new self test versions have extra chip. I wonder how they could fit it all inside.

 

[mbrooke]

Thanks so much for the references esp the GFCI breakers. I have been looking for them the past 4 months. If you know how the Siemens Gfci looks inside. Pls share. I used to suspect if i had counterfeit gfci breakers. I heard there are several hundred thousand counterfeit breakers..i wonder if there are counterfeit gfci breakers too. Im tempted to fry open my 60A siemens breakers. Its being sold cheap at amazon compared to their 30A siemens gfci breakers.

Unfortunately I do not, but imagine the construction is similar.

 

[kwired]

Fascinating. Even if you cannot officially return for warranty replacement, I am sure there are engineers in the company who would love to take a look at that breaker.

I think he can return it, it just so happens in his circumstances it will cost him as much or more to do so than simply buying a replacement.

Could easily be one component is defective and was not rejected by QC, might not even be an issue with an entire run of product, just that one individual piece had a defect.

 

[tersh]

Unfortunately I do not, but imagine the construction is similar.

Mbrooke. Do you know the internals of the General Electrical

TQD22150​

https://www.amazon.com/General-Electric-TQD22150-Circuit-Breaker/dp/B00ECKRIYK

Before my family got the townhouse in the 5 house compound. The breakers outside were already opened to the elements.. meaning when it rains hard, all the breakers get wet.

Can rain get inside the breakers? Are the plastic casing of most breakers waterproof? Because if the inside thermal and magnetic strips were already rusted. Maybe they won't function anymore and the breakers won't trip at all?

I want to see behaviors of breakers constantly exposed to rain (worse case scenario). How would the inside look like. Rusty?

To replace the breakers above. All 5 house owners must cooperate and need signatures to apply for electrical permit and power interruption to replace them. But most won't cooperate and spend money to buy new one and don't mind it.

 

[mbrooke]

Mbrooke. Do you know the internals of the General Electrical

TQD22150​

https://www.amazon.com/General-Electric-TQD22150-Circuit-Breaker/dp/B00ECKRIYK

Before my family got the townhouse in the 5 house compound. The breakers outside were already opened to the elements.. meaning when it rains hard, all the breakers get wet.

Can rain get inside the breakers? Are the plastic casing of most breakers waterproof? Because if the inside thermal and magnetic strips were already rusted. Maybe they won't function anymore and the breakers won't trip at all?

I want to see behaviors of breakers constantly exposed to rain (worse case scenario). How would the inside look like. Rusty?

To replace the breakers above. All 5 house owners must cooperate and need signatures to apply for electrical permit and power interruption to replace them. But most won't cooperate and spend money to buy new one and don't mind it.

Oh, this is easy! UL did a residential aging report, and the majority of the breakers that failed to trip where outdoors (in a rain proof enclosure)- I can only imagine here where they are actually being rained on.


I do not know the internals, but it would not shock me if they have all seized up considering the above is a code violation. Breakers must be protected from water.

 

[tersh]

Oh, this is easy! UL did a residential aging report, and the majority of the breakers that failed to trip where outdoors (in a rain proof enclosure)- I can only imagine here where they are actually being rained on.


I do not know the internals, but it would not shock me if they have all seized up considering the above is a code violation. Breakers must be protected from water.

Ok. Thanks for the info. Need to convince the neighbors. Lol.

Well. I'm presently studying about arc flash. How many current in a wire before it can become explosive enough to injure the electrician?

https://www.youtube.com/watch?v=6hpE5LYj-CY

Once I saw an electrician trying to connect a breaker live. Although there is no direct connection between two terminals. There are carbon sooths, and this created a small arc flash enough to injure him. After that. I won't even go near an electrician when he fixed stuff. And also staying from the electronic or electrical engineering field as it's very dangerous field.

In the Philippines where electricians don't have to worry about neutral and grounding, but just able to connect the red and black wires without even polarity. Many of them are doing it live (only skill they can boost that cut them above ordinary folks). I know this is very dangerous. Many of them don't even know what is arc flash.

I want to share them this so they be more careful. In a basic home panel. What usually is the current before the arc flash can occur similar or even half the video (above) intensity?

And if AFCI are installed. Can it totally prevent it or just diminish the intensity (by how many percentage)?

 

[mbrooke]

Ok. Thanks for the info. Need to convince the neighbors. Lol.

Well. I'm presently studying about arc flash. How many current in a wire before it can become explosive enough to injure the electrician?

https://www.youtube.com/watch?v=6hpE5LYj-CY

Once I saw an electrician trying to connect a breaker live. Although there is no direct connection between two terminals. There are carbon sooths, and this created a small arc flash enough to injure him. After that. I won't even go near an electrician when he fixed stuff. And also staying from the electronic or electrical engineering field as it's very dangerous field.

In the Philippines where electricians don't have to worry about neutral and grounding, but just able to connect the red and black wires without even polarity. Many of them are doing it live (only skill they can boost that cut them above ordinary folks). I know this is very dangerous. Many of them don't even know what is arc flash.

I want to share them this so they be more careful. In a basic home panel. What usually is the current before the arc flash can occur similar or even half the video (above) intensity?

And if AFCI are installed. Can it totally prevent it or just diminish the intensity (by how many percentage)?

Honestly, I am not well versed in arc flash. I have the blessing of thinking about open air buswork 20 or more feet in the air where the blast is not all the bad from the ground and clears within 5-15 cycles.

However, there are experts here on Holt which can tell you EVERYTHING from the science down to the PPE.

BTW, an AFCI may not do much. AFCI breakers are very much in their infancy truth be told.


Having an instantaneous function like magnetic trip or GFP helps, but again, I am no expert.