How to calculate Temperature Correction Factor for Tan Delta Measurement?
As per Standard the value of Tan Delta measured at 20 deg C should not be more than 0.007.
Lets say Tan Delta measured at 35 deg C is 0.0025.
We need to Calculate Corrected Tan Delta at 20 deg C.
This is done with the following formula:
Tan Delta Corrected = Tan Delta Measured at Ambient temp. / k
Where K = 0.6428 x e^(0.0222 x Temperature)
In this case, K = 0.6428 x e^(0.0222 x 35) = 1.40
Therefore Corrected Tan Delta @ 20 Deg C = 0.0025 / 1.40 = 0.0017
Please find readymade table for Constant K at various Temperature.
In case of Current Transformer Ambient Temperature to be considered for Tan Delta Temperature Correction Factor.
In case of Power Transformer/ICT, WTI Temperature to be considered.
