Figure. 5.4.11. - 71. Selectable measurement magnitudes with 2LL+U4 VT connection. If no residual voltage is connected
phase-to-earth voltages are not available.
P-P Voltages
and
P-E Voltages
selections follow phase-to-neutral or phase-to-phase voltages in the
rst three voltage channels (or two rst voltage channels in 2LL+U3+U4 mode).
U4 input
selection
follows voltage in channel 4.
U3Input
selection follows only the voltage in channel 3 if 2LL+U3+U4
mode is in use.
Pick-up characteristics
Pick-up of the OV function is controlled by
Uset
setting parameter, which de nes the maximum allowed
measured voltage before action from the function. The function constantly calculates the ratio in
between of the
Uset
and measured magnitude (Um) per all three voltages. Reset ratio of 97 % is
inbuilt in the function and is always related to the
Uset
value. The setting value is common for all
measured amplitudes and single-, dual- or each voltages Um exceed above the
Uset
value will cause
pick-up operation of the function.
Table. 5.4.11. - 112. Pick-up characteristics setting
Name
Description
Range
Step
Default
Operation mode
Pick-up criteria selection
0: All faults
1: P-P faults
2: Only 3P faults
-
0:All faults
Uset
Pick-up setting
50.00 … 150.00%Un
0.1%Un
120%Un
The pick-up activation of the function is not directly equal to start-signal generation of the function.
Start signal is allowed if blocking condition is not active.
Real-time info displayed by the function
The relays Info-page displays useful information in real time of the state of the protection function either
through relays HMI display or with AQtivate software when connection there is a connection to relay
and Live Edit-mode is activated.
Name
Unit
Description
U< Pick-up setting V
Primary voltage required for tripping. The displayed pick-up voltage level depends on the pick-
up setting and the voltage transformer settings.
Expected
operating time
s
Displays the expected operating time in case a fault occurs
AQ-F255
Instruction manual
Version: 2.00
© Arcteq Relays Ltd
124