ABB Power Grids Ltd.
GKSL 680205.021 RE
Rev. 2, 26.09.2019
13
11
Analysis of test results
The measured and corrected tg
δ
1
value is compared with that in the routine test report.
A considerable difference of the capacitance C
1
from a value of the test report (more 5%) may indicate a
damage (transportation- or assembly-caused), so such bushing must not be used.
A value C
2
depends on the way the bushing is embedded into the transformer and is not used for diagnostic.
The value tg
2
is also not used for bushing diagnostic (see section 10.1).
During operation, the insulation of the bushing is aging, as evidenced by an increase in the value of tg
1
.
The limiting value of tg
1
. should not exceed 0.7%.
An increase in the capacity C1 during operation may indicate a breakdown of one or more layers of the
bushing insulation.
Upon reaching the limit value tg
1
. or increasing the capacity
C1
by more than
5%,
please contact ABB
Power Grids Ltd., Russia for recommendations on the possibility of further operation of the bushing.
The service life of the bushing is at least 30 years.
12 Disposal
After reaching the end of lifetime, this product has to be disposed correctly according local laws and
regulations.
All the contained substances and material should be recycled separately. The product as a whole and its
individual parts do not contain any toxins.
Nether breathing- nor skin protection nor any special precautions are required. Apply the common and
appropriate safety standards to prevent working accidents. In case of uncertainties please contact ABB
Power Grids Ltd., Russia for advanced information and instructions.
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Scope of delivery
The scope of delivery of each bushing shall include documentation and components:
1. Documentation
Test report
Operational manual
Dimensional drawing
Packing sheet
2. Components
Test adapter (1 item)
Terminate plate (as specified in the order).
