5
Frequency Response Analyzer as well as enclosure and core of the “tested transformer”
are grounded together.
3.2 Winding Wiring Mode
Figure 2 Wiring type
It is recommended to input frequency sweep signal of winding deformation frequency
response test from tail end of winding and output from initial end, suspended for
non-tested winding. Wiring mode of winding deformation test varies with different wiring
group of the transformer.
YN Wiring
Input impedance of frequency sweep signal is connected to neutral point O and output
impedance to A, B and C respectively. For the measuring method, interference signal
received by non-measured phase is absorbed by low impedance of the signal generator,
as shown in Figure 3.
Figure 3 YN Wiring
Y Wiring
It is required to wire in the following manner as neutral point has no outgoing wire, as
shown in Figure 4.
In this test, input impedance is connected to A and output impedance to B.
In this test, input impedance is connected to B and output impedance to C.
In this test, input impedance is connected to C and output impedance to A.
Figure 4 Y Wiring
