Omicron CP TD1 Reference Manual

67
Power Transformers
Possible Faults and Possible Findings
Table 6-2 Possible Faults and Possible Findings [3.3]
Key gases Possible Faults Possible Findings
H
2
, possible trace of
CH
4
and C
2
H
6
.
Possible CO.
Partial discharges
(corona)
Weakened insulation
from aging and electrical
stress
H
2
, CH
4
(some CO if
discharges involve paper
insulation).
Possible trace amounts
of C
2
H
6
.
Low energy discharges
(sparking). May be static
discharges.
Pinhole punctures in
paper insulation with
carbon and carbon
tracking.Possible carbon
particles in oil.Possible
loose shield, pour
grounding of metal
objects.
H
2
, CH
4
, C
2
H
6
, C
2
H
4
and the key gas for
arcing C
2
H
2
will be
present perhaps in large
amount. If C
2
H
2
is being
generated, arcing is still
going on. CO will be
present if paper is being
heated.
High energy discharges
(arcing).
Metal fusion (poor
contacts in tap changer
or lead connections).
Weakened insulation
from aging and electrical
stress. Carbonized oil.
Paper destruction if it is
in the arc path or
overheated.
H
2
, CO. Thermal fault less than
300°C in an area close
to paper insulation
(paper is being heated).
Discoloration of paper
insulation. Overloading
and/or cooling problem.
Bad connection in leads
or tap changer. Stray
current path and/or stray
magnetic flux.
H
2
, CO, CH
4
, C
2
H
6
,
C
2
H
4
Thermal fault between
300°C and 700°C.
Paper insulation
destroyed. Oil heavily
carbonized.
All the above gases and
acetylene in large
amounts.
High energy electrical
arcing. Thermal fault of
700°C and above.
Same as above with
metal discoloration.
Arcing may have caused
a thermal fault

Omicron CP TD1 Specifications

General

Brand	Omicron
Model	CP TD1
Category	Measuring Instruments
Language	English