Spacing Considerations Between Substation Buildings And Liquid Type Transformers

Substation buildings exist at every petrochemical facility; located at the incoming power high-voltage substation or switchyard through all levels of distribution downstream. Typically, large, liquid type transformers are located near these substations to step voltages down to levels required by process units or other loads. This paper examines current industry standard requirements and recommendations, fire considerations, and best engineering practices used when installing new liquid type transformers, or retrofilling existing liquid type transformers with several types of dielectric liquids. The scope of this paper is limited to in-plant power distribution outdoor transformers that have secondary voltages ranging from 480 V to 35 kV and are also limited to installations subject to ANSI/NEMA codes and standards.