circuit breakerelectricalelectrical-panel
I have an ITE electrical panel from the 1970's. We noticed some flickering in the bathroom and some noise coming from the electrical box. There was a single breaker arcing in the panel. I pulled it and attempted to move another breaker to this slot and it did the same.
So it seems I have some sort of corrosion on this slot of the busbar. I was wondering for anyone that has experience with this, is there a recommended way to clean and potentially grease this one spot to ensure better contact?
The panelboard will be bonded to ground, and according to the National Electrical Code (NEC) it must be done so using specific methods.
250.8 Connection of Grounding and Bonding Equipment.
(A) Permitted Methods. Grounding conductors and bonding jumpers shall be connected by one of the following means:(1) Listed pressure connectors
(2) Terminal bars
(3) Pressure connectors listed as grounding and bonding equipment
(4) Exothermic welding process
(5) Machine screw-type fasteners that engage not less than two threads or are secured with a nut
(6) Thread-forming machine screws that engage not less than two threads in the enclosure
(7) Connections that are part of a listed assembly
(8) Other listed means(B) Methods Not Permitted. Connection devices or fittings that depend solely on solder shall not be used.
If the specific method used in your situation fits one of the methods listed above, then the panelboard is likely grounded properly. The ground and neutral bus bars inside the panel are surely bonded to the panel itself using one of these methods. Which means as long as the panel is connected to the system grounding conductor using an approved method, the system should be properly grounded.
If you have doubts as to whether or not the installation is correct. Contact your local government and check on any permits that were obtained for the work, and/or request the installation be inspected by the local electrical inspector.
Probably. Here's a diagram of how a main panel and a subpanel are usually wired together:
In this diagram:
So if this behavior matches up with what you are experiencing when flipping breakers, then you're probably OK. Obviously there will be slight differences, such your breakers will probably not be in the same positions in my example, the pair of breakers in your main panel might just be one double-wide breaker, or (unlikely) the pair of breakers in your main panel might just be a single breaker.
But if you're concerned, it is worth it to pay a second electrical contractor to come out and look over the other guy's work. Also, the work should have required permits and therefore an inspection by a government inspector. If that didn't happen, then that might be a red flag.
Also, new electrical work like this must be labeled properly to meet code in most jurisdictions. You are will within your right to call the electrician and insist he properly label his work.
Best Answer
A picture postcard example of "wrong breaker type"
Note the alien breaker in position 27, a GE, an obvious misfit. If that one is still working, it's only because it hasn't been put under heavy load as this one was.
People who think "if it snaps in, it's good" fail to notice that the snap-in pressure is all wrong compared to proper breakers. That's because even though breakers often roughly fit, each manufacturer's busbar is a different shape. The correct breaker gets surface contact. The wrong breaker gets edge or corner contact - works for a few lights but when you load it, it starts arcing. Since this is on the supply side of the breaker, nothing stops this. Anyway it's a series arc, current won't be more than the load's draw.
Siemens makes correct breakers for ITE panels.
The contact isn't corroded. It is destroyed. The arcing removed metal from the contact. The metal is gone, and cannot be restored. That slot is done for and you will not be fitting breakers there anymore.
Your best bet is to plug the hole with something. Your choices are a panel hole cover UL listed for that panel, though those can be hokey and hard to find; or a spare Siemens/ITE breaker, labeled "Unused", under $5.