Ambient temperature and power reduction

The rated ambient temperature is the highest temperature at which the transformer can be operated continuously under specified operating conditions. Unless otherwise agreed, the transformers are designed for a maximum ambient temperature of 40 °C.

The transformers must be installed so that the necessary cooling is guaranteed. This must be taken into account, especially in enclosures with a high degree of protection. Transformers with cooling ducts must be installed in such a way that the ducts are positioned vertically. Deviating from 40 °C ambient temperature, the rated power according to the following table must be reduced for higher temperatures.

Ambient temperature 45°C 50°C 55°C 60°C
Reduced power 95 % 85% 80% 75%