A programmable circuit breaker, including an input unit, a sensor, and, a trip mechanism. The input unit permits user input and/or adjustment of predetermined load parameters. The sensor senses actual values of a load. A microcontroller receives and processes the values, and operates/trips the circuit breaker when the sensed values exceed predetermined load parameters. The sensor preferably includes a Hall-Effect sensor. The circuit breaker is preferably able to be programmed, monitored and/or tripped remotely. It preferably includes an RCD. In a power distribution system, at least one such current breaker is provided, controllable by a controller, which may be remote from the current breaker.