ABB REC 561 User Manual page 278

ABB Network Partner AB
Version 1.0-00
Loss of power system voltage
1.11 Increase the measured voltages to their rated values for at least 10
seconds. Simultaneously decrease all three voltages to a value that
is at least 10% higher than the set operating value (settings are per-
formed under the under-voltage protection function). Simultane-
ously decrease in small increments all three voltages and wait
between each increment for at least eight seconds until the LOV--
TRIP signal appears on the corresponding binary output. Record
the measured operating voltage and compare it with the set value.
The result should be within the accuracy limit of +2.5% of Ur with
additional accuracy of the testing equipment used.
1.12 Disconnect the testing equipment. Do not forget to configure the
terminal, if necessary, to its normal operating configuration.
1MRK 580 153-XEN
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