Which of the following is NOT a function of circuit breakers?

Circuit breakers are designed to protect electrical circuits and systems by interrupting current flow under certain conditions. One of their primary functions is overcurrent protection, which involves disconnecting the circuit when the current exceeds a predetermined level, preventing overheating and potential damage. They also provide short circuit protection by quickly disconnecting the circuit in the event of a fault where the current flow drastically increases, which can cause severe damage or even fires.

Another important function of circuit breakers is system isolation. They allow for safe maintenance and repair of electrical circuits by disconnecting parts of the system from the power supply.

However, voltage regulation is not a function of circuit breakers. Voltage regulation refers to maintaining a stable voltage level within a system and is typically managed by devices such as voltage regulators or transformers. Therefore, while circuit breakers play a crucial role in protecting circuits from overcurrent and faults, they do not contribute to regulating voltage levels.