Power Transformer- Cooling Methods -Mixed Cooling

Mixed Cooling

ON/OB: As ON, but with alternative additional air-blast cooling.

ON/OFN, ON/OFB, ON/OFW, ON/OB/OFB, ON/OW/OFW: Alternative cooling

conditions in accordance with the methods indicated. A transformer may have two or three
ratings when more than one method of cooling is provided.