How do you find the temperature of a transformer hot spot?

gc for low voltage winding = 20.16 × ( )1.6 = 18.130C Hot spot temperature (θh) = top liquid temperature (θ0) + (h × gc), Where H=1.3(for power transformer) or 1.1(for distribution transformer).

How much heat does a transformer give off?

Transformers typically can tolerate a maximum of 104°F but check with manufacturer. If you exhaust high over the equipment & supply air low, by stratification you may be able to reduce air supply required. But it is better to be safe than designing it too close.

What temperature should a transformer run at?

The average ambient temperature for a transformer over a 24 hour period should not exceed 30 degrees Celsius. For instance, if the transformer ambient temperature was 40 deg. C for 12 hours, then the transformer must not exceed 20 deg. C for the remaining 12 hours to average a 30 deg.

What is WTI and OTI?

The WTI means winding temperature Indicator and OTI means Oil Temperature Indicator which indicates the winding temperature & oil temperature of the transformer and operates the alarm, trip, and cooler control contacts. This instrument operates on the principle of thermal imaging and it is not an actual measurement.

What is high transformer temperature?

Standard Ratings and Overload Capacity Liquid-filled transformers come in standard rises of 55C and 65C. These values are based on a maximum ambient temperature of 40C.

What is hotspot temperature?

The temperature of solid insulation is the main factor of transformer aging. With temperature and time, the cellulose insulation undergoes a depolymerization process. The rated hot spot temperature for this kind of paper is 110°C and it can be seen that an increase of 7°C will double the aging acceleration factor.

How do you calculate the heat of a transformer?

Thus, the heat dissipation is dependent upon the total exposed surface area of the core and the total exposed surface area of the windings. PΣ = total transformer losses (power lost and dissipated as heat) in mW; AT = surface area of transformer in cm2.