25-06-2012, 05:32 PM
Transformer heat run test: The loading back method
Transformer heat run test.ppt (Size: 142 KB / Downloads: 434)
Standard Requirement: C57.12.90 clause 11
Duplicate (not nessary) transformers may be tested by connecting their respective high-voltage and low-voltage windings in parallel (see Figure 27 and Figure 28). Transformers shall be tested with the combination of connections and taps that give the highest average winding temperature rise. This will generally involve those connections and taps resulting in the highest losses.
Loading back method
Transformer 1: transformer under test
Transformer 2: « source » transformer
S1: variable source, provides essentially the total iron losses
S2: variable source, provides essentially the copper losses