64
Installation and commissioning guide
2750 515-1 EN, REV. 14, 2020-06-26
* Reference values from ABB Components.
Dissipation factor, tan δ
The dissipation factor varies with the temperature of the bushing core, and thus the measured dissipation
factor must be multiplied with the correction factor given below.
Bushing core temperature °C
Correction factor to 20 °C (IEC)
0-2
0.80
3-7
0.85
8-12
0.90
13-17
0.95
18-22
1.00
23-27
1.05
28-32
1.10
33-37
1.15
38-42
1.20
43-47
1.25
48-52
1.30
53-57
1.34
57-62
1.35
63-67
1.35
68-72
1.30
73-77
1.25
78-82
1.20
83-87
1.10
Procedure
1.
De-energize the transformer.
2.
Disconnect the external connections from the outer terminal of the bushing.
3.
Remove the cover (58).
G005047
