IS THERE A MULTIPLE MVA RATING FOR TRANSFOMER WITH OIL DIRECTED WATER FORCED COOLING (ODWF)?
IS THERE A MULTIPLE MVA RATING FOR TRANSFOMER WITH OIL DIRECTED WATER FORCED COOLING (ODWF)?
(OP)
Hello,
I am familiar with Transformer MVA rating being increased based on the type of cooling. For instance, Transformer with ONAF type cooling, will have two MVA ratings. One rating for the oil natural cooling by convection and other higher rating with air forced type cooling using fans.
Does any body familar with Oil Driven Water Forced (ODWF) type cooling? Does transformers with this type (ODWF)of cooling also has multiple rating?
Regards,
Subash
I am familiar with Transformer MVA rating being increased based on the type of cooling. For instance, Transformer with ONAF type cooling, will have two MVA ratings. One rating for the oil natural cooling by convection and other higher rating with air forced type cooling using fans.
Does any body familar with Oil Driven Water Forced (ODWF) type cooling? Does transformers with this type (ODWF)of cooling also has multiple rating?
Regards,
Subash






RE: IS THERE A MULTIPLE MVA RATING FOR TRANSFOMER WITH OIL DIRECTED WATER FORCED COOLING (ODWF)?
RE: IS THERE A MULTIPLE MVA RATING FOR TRANSFOMER WITH OIL DIRECTED WATER FORCED COOLING (ODWF)?
RE: IS THERE A MULTIPLE MVA RATING FOR TRANSFOMER WITH OIL DIRECTED WATER FORCED COOLING (ODWF)?
There is no "oil natural" rating with ODWF transformers because the oil pump and cooling water should always be running while the transformer is in service.
RE: IS THERE A MULTIPLE MVA RATING FOR TRANSFOMER WITH OIL DIRECTED WATER FORCED COOLING (ODWF)?
These types of transformers are very commonly used in hydro-electric power generating stations world wide.
The last part of mgtrp's post above is correct - - the only modifier would be in very cold weather; see my anecdote in the thread at
http://www.eng-tips.com/viewthread.cfm?qid=358868
Hope this helps, although it might not, since there may after all never be any "very cold weather" where you are...
CR
"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]
RE: IS THERE A MULTIPLE MVA RATING FOR TRANSFOMER WITH OIL DIRECTED WATER FORCED COOLING (ODWF)?
1) At aluminum smelters, arc furnace steel mills etc. Here OFAF coolers will not be effective due to heay dust deposit on cooler tubes.
2) At urban areas, for underground substations.
Even at hydro power stations if space is available OFAF coolers are used to reduce maintenance issues. But for underground power stations there is no other alternative.