Version 3.03
WR14 / WR50-12/13 Winding Resistance Meter Instruction Manual
108
Example:
The following is an example of a transformer prepared for a Heat Run testing, utilizing a WR-14 and a
WR50, having the following nameplate:
HV:
66KV, 78.8A
LV:
11KV, 473A
At the moment, the source providing power to heat the transformer should be switched off. Press the
Timer on both Winding Resistance meters. This will set the base start time. Connect the measuring
cables from the WR14 to the high voltage side of the transformer and connect the measuring cables
from the WR50 to the corresponding
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winding of the low voltage side.
Start the measurement on the high voltage side first with the WR14 set to "interval mode" with a Current
of 7A
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After the current is flowing on the high voltage side, Start the measurement on the low voltage side with
the WR50 set to "interval mode" with a current of 40A.
After the results are obtained, stop the current on the low voltage side first (WR50) and then stop the
current on the high voltage side (WR14).
Now you can analyze the test results with the optional heat run test software to calculate the cooling
curve. A description of this sof
tware can be found in “Heat Run Test Software” on page 65. Or you may
export the results on a computer and analyze the data with our Software “T-Base Pro”.
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See the previous chapter,
“Measuring High- and Low-Voltage-Side in Series” on page 104.
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Ensure that the test current does not exceed 10% of the rated winding current; this could cause
erroneous reading due to heating in the windings.
