Arc detection using load recognition, harmonic content and broadband noise

A controller for a system for determining whether arcing is present in an electrical circuit in response to input signals, said input signals corresponding to a changing current in said circuit and to the presence of broadband noise in a predetermined range of frequencies in said circuit, said controller comprising:

• a plurality of counters;
• means for incrementing one or more of said plurality of counters in accordance with said input signals and
• means for determining a type of load connected to said electrical circuit and whether an arcing fault is present using at least the states of one or more of said plurality counters.

A method of determining whether arcing is present in an electrical circuit in response to input signals, said input signals corresponding to a changing current in said circuit and to the presence of broadband noise in a predetermined range of frequencies in said circuit, said method comprising:

• incrementing one or more of a plurality of counters in accordance with said input signals;
• and
• determining a type of load connected to said electrical circuit and whether an arcing fault is present using the states of one or more of said plurality of counters.