Schneider Electric Recalls PowerPact J-Frame Circuit Breakers Due to Fire, Burn, Electrical Shock Hazards
No need to spam other threads.
Question: Would a bad breaker panel harm appliance?
An electrician mentioned to me that a bad distribution board (also known as panelboard or breaker panel) can harm appliance. He mostly relates the potential cause to surge through panel, while a surge can be due to lightening etc. He particularly referred to a bad panel removed this morning that has half of the channel showing signs melting.
I don’t understand the above concept for the following reasons and would bring this here for discussion.
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A panel breaker serves to protect the electrical appliance in home. When there is current higher than a set limit, the circuit breaker will trip and shut off the electricity. So the panel can only do protection than harm as long as the circuit breakers are functioning. Even if the breaker fails to trip, we can only blame it not doing its job but to accuse it as the source of damage, or it causes the damage. -
The breaker will fail to protect the appliance when a surge takes place too fast for the circuit breaker to react and trip. However, this should blame the circuit breaker rather than the panel channel itself. The panel channels are conducting current. A brand new panel channel won’t do any better than an old one that has flaws in protecting the home appliance from surge. -
Would the panel channel that has signs of melting be less conductive and therefore outputs less voltage. I doubt about it. But even if it is the case we have the following argument. Less output voltage may cause an appliance not functioning properly. But less output voltage also means less capability of doing damage. When the proper power is charged, the appliance should come back to work normal. -
It’s my understanding that the worst scenario for panel breaker to go bad is that it lost its capability to protect the home appliance, but not that it will become harmful to the appliance. If a panel breaker itself does the adverse thing, i.e., to harm the appliance, then that will be a big issue to the panel manufacturers.
Yup. Got that email.
Firstly not the best message board to bring that question up to. I would direct you over to Mr.Holts website for this type of discussion. However, since you are here I will answer your questions for you. Here are your questions in order…(my responses are in RED)
Q1) You Asked - A panel breaker serves to protect the electrical appliance in home. When there is current higher than a set limit, the circuit breaker will trip and shut off the electricity. So the panel can only do protection than harm as long as the circuit breakers are functioning. Even if the breaker fails to trip, we can only blame it not doing its job but to accuse it as the source of damage, or it causes the damage.
A1 -The OCPD is intended to protect the conductors supplying the appliance. The OCPD is sized based on the conductor and not the actual appliance itself. however, the protection afforded the conductor also translates directly to the appliance indirectly. If the Circuit Breaker fails in a position that it would permit electricity to flow even in the off position then it would be a failure of the circuit breaker. The appliance will pull a set ampacity value that you originally sized the conductors too so it is not likely the appliance will be affected unless something happens in the appliance that allows an excessive amount of current to flow.
Q2) You Asked - The breaker will fail to protect the appliance when a surge takes place too fast for the circuit breaker to react and trip. However, this should blame the circuit breaker rather than the panel channel itself. The panel channels are conducting current. A brand new panel channel won’t do any better than an old one that has flaws in protecting the home appliance from surge.
A2) The reality is that brand new circuit breakers are not designed to protect against nano spikes or surges. The customer would need to have a SPD, Surge Protective Device in order to absorb the effects of a surge but the circuit breaker is not designed to account for this line side affect. A circuit breaker (in general) is designed to look for Overcurrent events which are overload, short circuit and ground fault…none of which are line side nano spikes or surges. Also the terminology is Load Center and the internal board is called Panelboard as just an FYI.
Q3) You Asked - Would the panel channel that has signs of melting be less conductive and therefore outputs less voltage. I doubt about it. But even if it is the case we have the following argument. Less output voltage may cause an appliance not functioning properly. But less output voltage also means less capability of doing damage. When the proper power is charged, the appliance should come back to work normal.
A3) This may be sorta true in theoretical terms. The lack of adequate voltage (remembering that voltage drop is not a requirement in the NEC, other than fire pumps) will cause motors to function differently, building up more heat and potentially prematurely fail over time. However time is the KEY !. The real problem is that in AC systems the lower the voltage the higher the amps and with a set voltage and set ampacity specification anything that deviates from that could cause harm to the function of the appliance.
Q4) You Asked - It’s my understanding that the worst scenario for panel breaker to go bad is that it lost its capability to protect the home appliance, but not that it will become harmful to the appliance. If a panel breaker itself does the adverse thing, i.e., to harm the appliance, then that will be a big issue to the panel manufacturers.
A4) the Circuit Breaker is designed to protect the branch circuit itself. The by-product of that is that since we size the branch circuit based on the appliances load (as with all loads) the circuit breaker (or fuse) provides a dual function so to speak. Again, it’s primary role is to protect the conductors and it’s insulation under a known condition (NEC)…if a circuit breaker is not functioning properly, a equipment ground fault current path is not established and their is an overload, ground-fault or Short Circuit in the branch circuit or the appliance which could affect the branch circuit…then indirectly a bad circuit breaker has indeed harmed the entire process. Keep in mind that is very rare…but its important to know the chain of potential damage…
Hope this helps…
Paul,
Thanks for your response, appreciated. The question I asked was a little bit too general, and therefore it’s a little hard for me grasp a clear y or n from your response. So let me make it more specific.
We have 40” TV plugged directly into a socket that has been there working for a while. Recently, it developed burning smell and then went dead. At about the same time, we found the dryer keep tripping off. Electrician came in and replaced the entire breaker box and line to the dryer. Sign of melting was found on the plug of pannelboard that accept the main feed to the panel box. The problem with the line to the dryer was that a nail was pinned in the middle of the cable. Now everything goes back normal. My question is if the TV damage was due to the short circuit of the TV itself, or is it related to the melting sign on the panel. Here are a few details, 1)the TV line is completely separated from the line to the dryer, 2) the circuit breaker to the TV appears still fine, 3) the melting sign appeared already aged(it must have been there for a long time). There has been no lightening etc. recently). Let me know what your comment is. Thanks!
[ Paul,
Thanks for your response, appreciated. The question I asked was a little bit too general, and therefore it’s a little hard for me grasp a clear y or n from your response. So let me make it more specific.
We have 40” TV plugged directly into a socket that has been there working for a while. Recently, it developed burning smell and then went dead. At about the same time, we found the dryer keep tripping off. Electrician came in and replaced the entire breaker box and line to the dryer. Sign of melting was found on the plug of pannelboard that accept the main feed to the panel box. The problem with the line to the dryer was that a nail was pinned in the middle of the cable. Now everything goes back normal. My question is if the TV damage is related to the panel. Here are more detailed that maybe related to this question. 1)the line to TV is a separate line from the line to the dryer, 2) the circuit breaker to the TV appears still fine functional, and 3) that the melting sign appeared already aged (it must have been there for a long time). There has been no lightening etc. recently). Let me know what your comment is. Thanks!](http://www.nachi.org/forum/)](“http://www.nachi.org/forum/”)
Paul, Forget to mention that the circuit breaker connecting to the TV also carried other socket/appliance. No other problems have been reported before and after the replacement of the panel breaker. All circuit breakers have been replaced together with the panelboard.