IEEE C57.91-1981 IEEE Guide for Loading Mineral-Oil-Immersed Overhead and Pad-Mounted Distribution Transformers Rated 500kVA and Less with 65 C or 55 C Average Winding Rise

standard by IEEE, 07/31/1981

Full Description

Scope

This guide covers general recommendations for loading 65 "C rise mineral-oilimmersed overhead and pad-mounted distribution transformers described in American National Standards and rated 500 kVA and less. (For transformers rated 501 kVA and larger, see ANSI/IEEE C57.92-1981, [31') Recommendations for 55 "C rise transformers are included in this guide because a substantial percentage of these transformers are still in service.

Abstract

New IEEE Standard - Superseded.General recommendations for loading 65 degrees Centigrade-rise mineral-oil-immersed overhead and pad-mounted distribution transformers are covered. Recommendations for 55 degrees Centigrade-rise transformers are included because a substantial percentage of these transformers are still in service. The recommendations are based on winding hottest-spot calculations only. Other factors that may limit the permissible load to lower values are listed. A method to establish winding temperature and loss of life by nomographs is given.

Product Details

Published: 07/31/1981 ISBN(s): 9780738143019 Number of Pages: 26 File Size: 1 file , 1.5 MB Product Code(s): STDSU08177