Thermal Magnetic Circuit Breaker Schematic

The thermal unit is comprised of a bimetal element located behind the circuit breaker trip bar and is part of the breaker s current carrying path.

Thermal magnetic circuit breaker schematic.

Small circuit breakers typically have a manual control lever to switch off the load or reset a tripped breaker while larger units use solenoids to trip the mechanism and electric motors to restore. The thermal trip unit protects against a continuous overload. When there is an overload the increased current flow heats the bimetal causing it to bend. Thermal magnetic circuit breakers contain two different switching mechanisms a bimetal switch and an electromagnet.

These circuit breakers are ideal for extreme ambient conditions feature fast breaking time and superior shock and vibration resistance. Magnetic circuit breakers have slightly higher interrupt capacity when running dc loads and some are also rated for either ac or dc currents. Thermal circuit breakers are also available as self resetting which in some unusual circumstances could also be a deciding factor. Thermal magnetic circuit breaker definition.

In american homes today thermal magnetic circuit breakers are the most common type. These are circuit breakers which utilize two components to detect electrical faults. The bimetal serves as a means of handling overcurrents. Designed for panel or plug in mounting.

Circuit breakers may also use the higher current caused by the fault to separate the contacts such as thermal expansion or a magnetic field.