aforementioned programs stored in rom 29 nvm 31 is an electrically erasable rom which is commercially available from national semiconductor company of santa clara california nvm 31 retains the circuit breaker control set points which can only be modified by command instructions introduced onto bus 25 via the transceiver 27 this is an important feature of this invention and prevents inadvertent modification of the trip set point data at the circuit breaker which could otherwise present a problem the set points stored in nvm 31 will be retained after all the electrical power to the breaker controller 10 is disconnected these data points could also be stored in ram 28 however upon loss of power the data would be lost a known approach to selecting trip data from memory uses a potentiometer to vary voltage values in relation to the values of the set points in memory this earlier approach however requires additional circuitry and utilizes memory space within the rom to store the trip point data which is less economically feasible than the nvm memory employed herein a further advantage achieved by use of an electrically erasable rom to store the breaker control set points is the ability to select certain features and functions for each user preference from a single breaker controller design this is achieved by assigning three bytes in the nvm 31 as the design option bytes and arranging the bytes in predetermined patterns during the breaker controller manufacturing process it is possible to encode the breaker controller to selectively enable or disable certain functions for example.