Signal
Description
Time base
U
L3
Ang
Angle of U
L3
voltage
5ms
The selection of the AI channel in use is made with a setting parameter. In all possible input channel
variations the pre-fault condition is presented with a 20 ms averaged history value from -20 ms from
START or TRIP event.
General settings
The following general settings define the general behavior of the function. These settings are static i.e.
it is not possible to change them by editing the setting group.
Table. 5.6.2 - 287. General settings of the function.
Name
Range
Default
Description
VTS LN
mode
1: On
2: Blocked
3: Test
4: Test/
Blocked
5: Off
0: On
Set mode of VTS block.
This parameter is visible only when
Allow setting of individual LN mode is enabled in
General menu.
Pick-up
The
Voltage low pick-up and Voltage high detect setting parameters control the voltage-dependent
pick-up and activation of the voltage transformer supervision function. The function's pick-up activates,
if at least one of the three voltages is under the set
Voltage low pick-up value, or if at least two of the
three voltages exceed the set
Voltage high detect value. The function constantly calculates the ratio
between the setting values and the measured magnitude for each of the three phases.
Table. 5.6.2 - 288. Pick-up settings.
Name
Range
Step
Default
Description
Voltage
low
pickup
0.05…0.50×U
n
0.01×U
n
0.05×U
n
If one the measured voltages is below low pickup value and two of the
measured voltages exceed high detect value the function's pick-up
activates.
Voltage
high
detect
0.01…1.10×U
n
0.01×U
n
0.80×U
n
Angle
shift
limit
2.00…90.00deg 0.10deg 5.00deg If the difference between the present angle and the angle 40 ms before is
below the set value, the function's pick-up is blocked.
Bus
fuse fail
check
0: No
1: Yes
-
1: Yes
Selects whether or not the state of the bus fuse is supervised. The
supervised signal is determined the "VTS MCB Trip bus" setting (
I/
O
→
Fuse failure inputs).
Line
fuse fail
check
0: No
1: Yes
-
1: Yes
Selects whether or not the state of the line fuse is supervised. The
supervised signal is determined by the "VTS MCB Trip line" setting (
I/
O
→
Fuse failure inputs).
The pick-up activation of the function is not directly equal to the START signal generation of the
function. The START signal is allowed if the blocking condition is not active. When the activation of the
pick-up is based on binary signals, the activation happens immediately after the monitored signal is
activated.
The voltage transformer supervision can also report several different states of the measured voltage.
These can be seen in the function's
INFO menu.
A
AQ
Q-M257
-M257
Instruction manual
Version: 2.07
378
© Arcteq Relays Ltd
IM00021
Summary of Contents for AQ-M257
Page 1: ...AQ M257 Motor protection IED Instruction manual...
Page 2: ......
