Cooling systems

Cooling method

The method of cooling is marked with a letter code which indicates the cooling medium and the way it is circulated. 

In case of oil-immersed transformers the cooling method is indicated with symbol consisting of four letters and in case of dry-type transformers without enclosure or with a ventilated enclosure this symbol consists of two letters.

  • first letter – winding medium,
  • second letter – winding motion,
  • third letter – external medium,
  • fourth letter – external motion.

Cooling method coding is defined in standards EN 60076 and EN60726:

Cooling medium A – air
G – gas other than air
W – water
Sposób wprawienia w ruch czynnika
N - chłodzenie naturalne
F - chłodzenie wymuszone przez sztuczne wprawienie w ruch czynnika chłodzącego

Examples of cooling method designations applied at Elhand are as follows:

  • AN - dry-type transformer without enclosure or with ventilated enclosure and with natural air cooling 
  • ANAN - dry-type transformer in enclosure with natural air cooling inside and outside the enclosure 
  • WF - dry-type transformer without enclosure or with enclosure, water cooled with forced circulation