Harry Cochranes comments on grounded transmission lines

[Trade Journal]

Publication: Transactions of the American Institute of Electrical Engineers

New York, NY, United States
vol. 35, no. 1, p. 379, col. 1

REPORT OF THE TRANSMISSION COMMITTEE

BY PERCY H. THOMAS, CHAIRMAN

II - EXPERIENCE WITH GROUNDED NEUTRAL ON HIGH-TENSION TRANSMISSION LINES.

From The Montana Power Company, Mr. H. H. Cochrane.

This company operates ungrounded, and believes this method preferable. Telephone operation is very satisfactory.

The typical protection for two transmission lines in parallel consists of three-pole overload relays at the generating station end of the line, operated by three current transformers in each line, and three-pole reverse-current relays operated by three current transformers and potential transformers in each line. The system has sufficient line charging current to trip relays when one wire of the system is grounded.

Keywords:	H. H. Cochrane
Researcher notes:
Supplemental information:
Researcher:	Elton Gish
Date completed:	February 1, 2011 by: Elton Gish;