The present invention concerns an interface module between a field bus and electrical equipment controlling and protecting an electric motor. The interface module includes an integrated circuit having data pins connected via input/output circuits to contacts or binary sensors or to coils or actuators of the electrical equipment. The data pins of the integrated circuit are connected via logic circuits to inputs or outputs which are greater in number than the data pins. The inputs/outputs are connected to coils or actuators and to auxiliary contacts or binary sensors of the electrical equipment.