Eaton BR2100st breaker

[retnoc]

Hello everyone,

Have 2 new shunt trip breakers newly installed for a 100amp range and a 20amp grill.

The 20amp works fine upon testing.
The 100amp caused the control panel breaker feed to buzz, until finally letting the smoke out of the 100amp shunt.

Is there a way to diagnose and repair the shunt trip, or simply replace it?

Thanks in advance.

 

[LarryFine]

Are you saying that the breaker is tripping, or the trip coil is burning out after tripping?

If the latter, most shunt-trips can not withstand the coil being continuously energized.

 

[kwired]

I'd guess one of two things happened.

1 you applied incorrect voltage to shunt coil.

2 shunt coil can not take continuous voltage but you applied continuous voltage.

Did the breaker trip but kept shunt coil kept buzzing? If so second thing mentioned above is likely what happened and you would likely somehow need to arrange it so the control power that goes to the shunt coil will be interrupted by the same breaker when it trips.

Larry posted as I was composing my reply. I think some shunt trip units will open circuit to the shunt coil after the breaker trips, but not all do.

 

[retnoc]

Are you saying that the breaker is tripping, or the trip coil is burning out after tripping?

If the latter, most shunt-trips can not withstand the coil being continuously energized.

The 20amp 2 pole tripped as designed(instantly)

The 100amp caused buzzing of the control panel breaker(attempting to trip, but wouldn't signal it successfully tripped) and yes I believe the coil burnt out.

 

[retnoc]

I'd guess one of two things happened.

1 you applied incorrect voltage to shunt coil.

2 shunt coil can not take continuous voltage but you applied continuous voltage.

Did the breaker trip but kept shunt coil kept buzzing? If so second thing mentioned above is likely what happened and you would likely somehow need to arrange it so the control power that goes to the shunt coil will be interrupted by the same breaker when it trips.

120v was applied, the 20amp trips and that the end of it, it appears the 100amp didn't fully engage the trip mechanism and kept trying to engage itself causing a burnout. Is this repairable or just get a new one?

 

[LarryFine]

The 20amp 2 pole tripped as designed(instantly)

The 100amp caused buzzing of the control panel breaker(attempting to trip, but wouldn't signal it successfully tripped) and yes I believe the coil burnt out.

The two should behave identically. Is the buzzing load-related or shunt-trip-related?

If you do replace it, rewire it so its power comes from the 20a ST or something else that loses power.

 

[retnoc]

The two should behave identically.

Is the buzzing load-related or shunt-trip-related?

Shunt trip, no real load on anything and only caused by the 100amp shunt trip. I separated them and tried them individually before letting the smoke out on my 3rd attempt over 5 minutes to understand why it was buzzing

 

[kwired]

Some larger frame breakers might be repairable. Most miniature breakers are throwaway regardless of what extra features might be installed.

 

[kwired]

Shunt trip, no real load on anything and only caused by the 100amp shunt trip. I separated them and tried them individually before letting the smoke out on my 3rd attempt over 5 minutes to understand why it was buzzing

Must not let all the smoke out yet if it still does something when you apply power to it.

If it is supposed to be able to take constant voltage to the shunt coil, then something maybe malfunctioned and it wasn't pulling in the armature of the trip unit from the first time.

If so I'd see if they will warranty it.

 

[brantmacga]

I’m pretty confident in saying the BR series ST breakers are only manufactured with 120v coils, and they are designed for continuous voltage. I think you got a dud, which has happened to me on several occasions. I would verify also that you didn’t apply 240v to this coil, but I’m guessing you fed the micro switches from a common circuit.