Business and Distribution
Department
MANTENANCE TEST
Workshop unit
DISTRIBUTION TRANSFORMER
SECTION A - GENERAL DATA
Location:
Date of installation:
Date of failure:
Manufacturer:
Serial Number:
Manufacturing:
Capacity [kVA]:
Rated Voltage [kV]:
Rated current [A]:
Phase:
Vector Group:
Tapping [%]:
Cooling type:
Imp. Voltage [%]:
Frequency [Hz]:
SECTION B - DETAIL LAB TEST REPORT
1. Insulation Resistance
2 . Recovery voltage
Connection
Test Voltage
MV to Earth, LV guarded
5000 V
LV to Earth, HV guarded
1000 V
MV to LV, Earth guarded
1000 V
o
Position RHV [Ω]
A-B
B-C
1 Min.
10 Min.
DAR
Test voltage [V]
4. Turn Ratio Test
C
RLV[mΩ]
C-A
PI
Time constant [s]
3. Winding Resistance Measurement, T=
Tap
30 Sec.
a-b
Error [%]
b-c
Phase A
c-a
Phase B
Phase C
1
2
3
4
5
5. Short circuit impedance test
Result at nor. Tap
6. Oil voltage breakdown test
Phase A Phase B Phase C
Step
5
% Excited current
%
Guarantee Value, [W]
No load loss
W
Load loss at Test Temp.
W
Vcc (%)
1
2
3
Average
Result
4
Impedance in ohm
BDV
Error (%)
7 - No Load Loss Test
Input Voltage
Current
V
A
Power factor
o
8 - Load Loss Test at Test Temperature
Voltage
V
Input current
Power factor
A
Tap pos.
C
o
Load loss at 75 C
W
Total loss
W
Guarantee Value, [W]
% Imp. Voltage
9 - WITHSTAND VOLTAGE TEST
Winding
MV to Earth
LV to Earth
10. Other comments:
Tested by:
Test date:
Voltage [kV]
50
3
Checked by
Frequency [Hz]
50
50
Time [sec.]
60
60
Result
Approved by
Version: PMT21003