Instruction manual
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AQ G3x7 Generator protection IED
85 (211
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Figure 3-49: The principal structure of the overvoltage function.
The general start signal is set active if the voltage in any of the three measured voltages is
above the level defined by pick-up setting value. The function generates a trip command
after the definite time delay has elapsed.
Table 3-31: Setting parameters of the overvoltage function
Parameter
Setting value, range
and step
Description
Operation
Off
On
Operating mode selection for the function. Operation can be
either enabled “On” or disabled “Off”. Default setting is “On”.
Start voltage
30…130 % by step of
1%
Voltage pick-up setting. Default setting 63 %.
Start signal
only
Activated
Deactivated
Selection if the function issues either “Start” signal alone or
both “Start” and after set time delay “Trip” signal.
Default is
that both signals are generated (=deactivated).
Reset ratio
1…10% by step of
1%
Overvoltage protection reset ratio, default setting is 5%
Time delay
0…60000 ms by step
of 1 ms.
Operating time delay setting for the “Trip” signal from the
“Start” signal.
Default setting is 100 ms.
3.2.13
U
NDER VOLTAGE
U<,
U<<
(27)
The undervoltage protection function measures three voltages. If any of them is below the
set pick-up value and above the defined minimum level, then a start signal is generated for
the phases individually.