Application of Partial Discharge Testing to Hydro Generator Maintenance

A new concept of two-way automatic communication for distribution systems, henceforth abbreviated as TWACS, is introduced in this paper. This paper restricts itself to the discussion of outbound signalling from the substation to the remote transponderance units at the customer premises. The outbound signaling is obtained by injecting single cycles of the 60 Hz system voltage in series with the system voltage. Injection into the neutral and phase wires and their ramifications are explained and the paper concludeswith field results obtained at several different utilities.