10-12-2022, 06:35 PM
In your photo, there appear two circuit breakers. They are considered self-reset-type circuit breakers or thermo breakers.
I don't know which one you are asking. But the large (black color, hexagons/rectangular shape) one, with two (2) thick red wires, is obviously for large amperage.
And the small rectangular shape one with 2 small/thin wires connected activates is the same thing, but obviously activates on smaller amperage.
How do they self-reset? It works on the principle of temperature expansion with metal (conducting amperage). When large amperage passes thru the metal contact, heat is generated, so contact metal expands, thereby cutting off the circuit. Once it cools down, it restores contacts, allowing current to pass through.
How do you test them? Remove and disconnect the wiring, then use a multimeter to measure between the two (2) contacts. They should normally be closed, reading should be nearly 0 ohms. If it's open, then the circuit breaker is bad.
I don't know which one you are asking. But the large (black color, hexagons/rectangular shape) one, with two (2) thick red wires, is obviously for large amperage.
And the small rectangular shape one with 2 small/thin wires connected activates is the same thing, but obviously activates on smaller amperage.
How do they self-reset? It works on the principle of temperature expansion with metal (conducting amperage). When large amperage passes thru the metal contact, heat is generated, so contact metal expands, thereby cutting off the circuit. Once it cools down, it restores contacts, allowing current to pass through.
How do you test them? Remove and disconnect the wiring, then use a multimeter to measure between the two (2) contacts. They should normally be closed, reading should be nearly 0 ohms. If it's open, then the circuit breaker is bad.
Joe Zhao @ Greenville TX 75402
2004 Newell Coach 701, 45-8, 4 Slides, Front Entry
Detroit Diesel 60 w/DDEC, Allison 6-Speed AT, ZF Suspension w/Steerable Tag, ZF Auto Traction Control