Commissioning
DTA 100 C
30 / 90
822-129-8
7.7.1
Instructions for sampling
Important:
In order to achieve reliable measurement results, all devices, containers and
tools that come into contact with the oil must be clean.
Follow the manufacturer's instructions and safety instructions for the relevant sampling
container or electrical device.
When sampling, ensure you follow the instructions given in the relevant standard.
Only take oil samples during dry weather. Avoid sampling during rain or if it is very
humid. High humidity adversely affects the measurement results.
Remove any impurities at the sampling port (e.g. on the transformer) and in the sampling
container.
Use separate sampling containers for each oil type.
Take the sample during regular operation of the electrical equipment.
Once the oil samples have been received by the laboratory, they must be left to stand in
the room for approximately 24 hours in order for any bubbling to subside and for the oil
to adjust to the room temperature.
Protect the sample against moisture and solar radiation.
Condensation adversely affects the measurement results. To prevent condensation,
ensure that the temperature of the oil to be tested corresponds to the ambient
temperature of 20°C ± 5°C before measuring.
Heat the sampling container to above the ambient temperature.
Note:
Some standards stipulate maintaining specific temperature conditions during the
measurement process. Further information: Chapter
Overview of standards
(on page 44)
Further information on sampling, handling the oil sample and cleaning can be
found in the current version of each of the following standards:
IEC 60475
IEC 60156
ASTM D923
ASTM D877
ASTM D1816
