ABB Network Partner AB
Loss of power system voltage
Version 1.0-00
1MRK 580 153-XEN
Page 5 - 96
Fig. 1 Loss-of power-system voltage- simplified logic diagram
4Setting
The set value of the operating level for the loss-of power-system voltage
function is the same as for the undervoltage protection function, inde-
pendent of whether the function is built in the terminal as an option. The
setting of the operating value occurs under the sub menu:
Settings
Functions
Group n
UnderVoltage
The voltage criteria for the loss-of-voltage supervision function must be
set lower than the minimum, expected-system operating voltage. It is sug-
gested to consider an additional 10% safety margin during the setting cal-
culations.
(X80153-1)
UCHL2 <
t
7s
&
t
10s
LOV--BC
1
UCHL3 <
V
&
&
t
3s
1
V
UCHL1 <
1
V
LOV--VTSU
LOV--TRIP
t
150ms
&
Block LOV=Yes
TEST-ACTIVE
&
TEST
1
V