Many years ago, I gained the knowledge that turning circuit breakers on and off a few times would help reduce contact resistance by wiping away resistive films at the contact surfaces. But now, I do not remember how I found that out. A brief Google search failed to find any such wisdom.
We have been having a significant amount of rain and the ocean is not all that far away. The circuit panel is accessible from outside. There is a breaker box with a cover and then another cover. That is, two covers have to be opened to get access to the breaker handles.
I began to notice fluctuations in the lamp brightness. My computer's UPS started to click in and out in synchronism with the dips in brightness. I measured the voltage at my microwave oven with a DVM. When the microwave turned on, it dipped as low as 75V. There was no microwave heating, but I was surprised that it timed out normally.
A few open close cycles on the breakers seemed to help, but this morning I got some light dimming again.
So here are my questions:
- Is off-on cycling of the breakers a good maintenance technique?
- How may cycles should be used? Put another way, how do you know if you have cycled a sufficient number of times?
- What kind of resistance or voltage drop is reasonable for breaker contacts?
Bill
-- Ferme le Bush