What are Class 2 transformers?

Class 2 transformers are power units that supply electricity to Class 2 circuits. These transformers are built for small control circuits or accessories, and are limited to safe power levels either with circuit breakers or inherently.

Class 2 transformers deliver a maximum of 100 watts with a maximum output voltage of 30 or less. The transformer's power limit decreases as voltage increases. Class 2 transformers support simpler wiring methods, are low powered and may be used without additional protection for power overload. Some units include a thermal fuse to limit temperatures in case of extended overload or a short circuit. A doorbell is an example of a class 2 transformer.