rockman7892
Electrical
- Apr 7, 2008
- 1,172
I was hoping that someone could help confirm my understanding of requirements for outdoor transformer installations as it relates to required separation distances to adjacent transformers and buildings.
When looking at Table 5 in the FM Global Loss Prevention datasheets it gives the required separation between transformer (measured from containment) to buildings. For FM approved liquid transformers the table gives distances for both non-combustible and combustible buildings.
The biggest question I had in understanding separation requirements was the differentiation between combustible and non-combustible buildings. In a HV substation environment would most pre-fabricated and block buildings be considered non-combustible? In looking at a previous project I did the prefabricated building type was a Type II-B buildings which I believe is a non-combustible unprotected type building. Although this type of building in unprotected is it still considered a non-combustible building to where the lesser of the two separation distances in the tables can be used (15ft as opposed to 50ft)
Also in the tables 10,000 gallons of oil seems to be the threshold for larger separation. I know oil volume varies by transformer but would you expect for a 138kV or 230kVA 75MVA unit to have more than 10,000 gallons of oil?
When looking at Table 5 in the FM Global Loss Prevention datasheets it gives the required separation between transformer (measured from containment) to buildings. For FM approved liquid transformers the table gives distances for both non-combustible and combustible buildings.
The biggest question I had in understanding separation requirements was the differentiation between combustible and non-combustible buildings. In a HV substation environment would most pre-fabricated and block buildings be considered non-combustible? In looking at a previous project I did the prefabricated building type was a Type II-B buildings which I believe is a non-combustible unprotected type building. Although this type of building in unprotected is it still considered a non-combustible building to where the lesser of the two separation distances in the tables can be used (15ft as opposed to 50ft)
Also in the tables 10,000 gallons of oil seems to be the threshold for larger separation. I know oil volume varies by transformer but would you expect for a 138kV or 230kVA 75MVA unit to have more than 10,000 gallons of oil?