Abstract: The invention is for an optical communication apparatus for bidirectionally transmitting and receiving supervisory and audio signals. The apparatus includes a telephone line interface unit that receives electric audio and supervisory signals and converts them to optical signals. It is also includes means for receiving optical signals representing audio and supervisory signals. A data unit receives the optical audio and supervisory signals from the interface unit and converts them to electric audio and supervisory signals, and also includes means for receiving electric audio signals and supervisory signals and converting them to corresponding optical signals. An optical link connects the telephone line interface unit and data unit for bidirectional optical communication. A method of practicing the invention is also included.

Abstract: A load management control system and method which communicates load shedding information from a central station controller via existing telephone lines to a substation controller. The substation controller in turn controls the tap position selection of a load tap changing transformer to send encoded step voltage signals down a power distribution line to a load control receiver. The load control receiver decodes the encoded signal message and appropriately controls uniquely associated loads. The substation controller interrupts automatic operation of the voltage maintenance circuitry of the load tap changing transformer during transmission of a message. Control is returned to the automatic circuitry of the load tap changing transformer after the message is completed so as to make existence of the load management control system of the present invention transparent to existing equipment in the field.