Pick-up
The
U
set
setting parameter controls the pick-up of the U< function. It de nes the minimum allowed
measured voltage before action from the function. The function constantly calculates the ratio between
the
U
set
and the measured magnitude (
U
m
) for each of the three voltages. The reset ratio of 103 % is
built into the function and is always relative to the
U
set
value. The setting value is common for all
measured amplitudes. When any
U
m
decreases below the
U
set
value it triggers the pick-up operation of
the function.
Table. 5.3.6. - 66. Pick-up settings.
Name
Range
Step
Default
Description
Undervoltage set U<
0.00...120.00 %U
n
0.01 %U
n
20 %U
n
The pick-up setting for undervoltage.
No voltage set U<
0.00…80.00 %U
n
0.01 %U
n
1 %U
n
The pick-up setting for no voltage.
Measured magnitude
0: P-P voltages
1: P-E voltages
-
0: P-P voltages
Selects the measured magnitude.
Pick-up terms
0: 1 voltage
1: 2 voltages
2: 3 voltages
-
0: 1 voltage
Selects the number of voltages to be protected.
Events and registers
The undervoltage function (abbreviated "EMON" in event block names) generates events and registers
from the status changes in ALARM events and NO VOLTAGE signals. The user can select the status
ON or OFF for messages in the main event buffer.
The triggering event of the function is recorded with a time stamp and with process data values.
Table. 5.3.6. - 67. Event codes.
Event number
Event channel
Event block name
Event code
Description
8652
135
EMON1
12
U< (27) detected ON
8653
135
EMON1
13
U< (27) detected OFF
8654
135
EMON1
14
U< (27) No voltage detected ON
8655
135
EMON1
15
U< (27) No voltage detected OFF
The table below presents the structure of the function's register content. This information is available in
the last twelve (12) recorded events for all provided instances separately.
Table. 5.3.6. - 68. Register content.
Date and time
Event
code
Fault
type
U
meas
/U
set
Used SG
dd.mm.yyyy
hh:mm:ss.mss
8652-8655
Descr.
A…A-
B-C
The ratio between the measured voltage and the
pick-up setting.
Setting group 1...8
active.
AQ-E215
Instruction manual
Version: 2.01
87
© Arcteq Relays Ltd