Omicron Lab CT Analyzer User Manual page 36

CT Analyzer User Manual
Figure 2-11 Measurement on a Y winding transformer
Measurement on a Δ (Delta) Winding Transformer
CTs outside the delta winding
For CTs that are located in the bushing outside of the delta winding (Figure
2-12), no delta compensation is needed.
In this case, only two parallel transformer windings are connected in series to
the CT. This connection method provides least possible influence to the
measurement result for the winding resistance of the CT.
The Y winding and the remaining windings of the power transformer's delta
winding are short-circuited to avoid influence of the induced flux of the power
transformer's core to the measurement.
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