an arc fault circuit breaker conducting an electric current to a protected load is presented . the circuit breaker has a first compartment and a second compartment . a bimetal resistor is disposed within the first compartment and conducts the current therethrough . the bimetal resistor has a stud extending into the second compartment . a single sense line is electrically connected to the bimetal resistor and routed into the second compartment . the sense line and said stud conduct a voltage signal indicative of arcing of the current . a circuit board is disposed within the second compartment and is connected to the sense line and stud within the second compartment to process the voltage signal . the circuit board has a first conductive path electrically connected to the stud , and a second conductive path electrically connected to the sense line . the first and second conductive paths run substantially parallel and proximate to each other such that electromagnetic interference of the voltage signal is substantially reduced .