What is the commonplace operating heat of a circuit breaker? What should the temp be for this circuit breaker? I have...
What should the temp be for this circuit breaker? I have a 3 pole 100 amp operating at 135, 140, and 125 degrees F using 60, 80, and 50 amps respective. The temps own increased dramatically in the last week short an increase in usage. I'm certain the evaluate of wire is correct. Temp measured by infra red. Breaker is GE THQB?
A circuit breaker is supposed to be loaded to 80% of its' size. So operating at 80 amps, and more for a length of time is going to cause heat build up.
Also, what is the ambient heat of the room?
Jim is right, that the connections need to be clean and tight.
Those temp reading are on the warm side.
If that is feed a panel, move the circuits around, to bring the amp readings of each leg closer to respectively other.
Since the amp draw is up the temperature will go up. This is ordinary physics. You are concerned correctly that the draw is up without increased usage. Try these steps to correct or locate the problem.
1. Tighten all of the connections surrounded by the circuit.
2. Inspect the lugs and connection tabs surrounded by the panel.
3. Verify voltage changes during the increased draw. If the voltage is different, the draw will change.
What is the circuit? 3 phase AC? Refrigeration?
If this is a commercial installation, name your electrical maintenance contractor.
You may want to do an electrical energy audit from your power company.
Answers: A rule of thumb for how hot a breaker can be is to see if you can tightly hold your hand against the breake for 5 second with out it being bleeding. I know it is not as scientific is an infa red but it is a fast mode to see if something needs attention.
You should replace the breaker if you tempter has increased dramatically within the past week with no nouns change. It could damages you panel and cost you a lot of money.
When breaker run bad they do heat up resembling this and can melt the bus bar of your panel. This could also be effect by a loose connection between the wires and the breaker.
I would replace the breaker either path. The cost of the breaker verses the cost of the panel is small. Make sure all your connections are tight and you may want to use Nolox antioxidant to verbs your connections.