Letter T

Thermal-Magnetic

Used to describe a device that uses both heat and magnetism
as part of its operating principles. For example, a thermalmagnetic
circuit breaker can be tripped either by heat or
magnetic force resulting from an overcurrent.



Thermistor
A device used to sense temperature that varies in resistance as
temperature changes.



Thyristor

A family of multi-layer semiconductor devices that includes
silicon controlled rectifiers (SCR), gate turnoff (GTO) thyristors,
and other similar devices. Thyristors are often used in rectifier or
power switching circuits.

Time-Current Curve

A graph showing how long before a circuit breaker will trip at
each level of fault current.