The TE (Potter & Brumfield) relays have fixed pick-up & adjustable drop-out; the Macromatic units have both adjustable pick-up & drop-out. The TE (Potter & Brumfield) relays that monitor DC voltages have a completely different pin configuration than the Macromatic equivalent products. If replacing the TE (Potter & Brumfield) unit with a Macromatic equivalent, please remember to change the wiring connections on the socket accordingly. Click here for additional information.