The power source module connects to a standard wall outlet to provide power to the other modules of the system. The voltage output of the power source depends on the local ac power network voltage. A thermal-magnetic circuit breaker provides overcurrent and short-circuit protection. If the intensity of the current flowing from the power source ever reaches a value greater than the breaker current rating for a certain length of time, the circuit breaker opens the circuit, thus preventing damage to the power source and other equipment.