Loss Of Voltage Check Lovptuv (27); Identification; Application; Setting Guidelines - ABB REB670 Applications Manual

1MRK 505 337-UUS -
8.5
8.5.1
8.5.2
8.5.3
8.5.3.1
Application manual
For fuse supervision normally only this alarm level is used and a suitable voltage level is
3-5% if the ratio correction factor has been properly evaluated during commissioning.
For other applications it has to be decided case by case.
tAlarm: The time delay for alarm is set by this parameter. Normally, few seconds delay can
be used on capacitor banks alarm. For fuse failure supervision (SDDRFUF) the alarm
delay can be set to zero.

Loss of voltage check LOVPTUV (27)

Identification

Function description
Loss of voltage check

Application

The trip of the circuit breaker at a prolonged loss of voltage at all the three phases is
normally used in automatic restoration systems to facilitate the system restoration after a
major blackout. Loss of voltage check (LOVPTUV, 27) generates a TRIP signal only if
the voltage in all the three phases is low for more than the set time. If the trip to the circuit
breaker is not required, LOVPTUV (27) is used for signallization only through an output
contact or through the event recording function.

Setting guidelines

Loss of voltage check (LOVPTUV, 27) is in principle independent of the protection
functions. It requires to be set to open the circuit breaker in order to allow a simple system
restoration following a main voltage loss of a big part of the network and only when the
voltage is lost with breakers still closed.
All settings are in primary values or per unit. Set operate level per phase to typically 70%
of the global parameter VBase level. Set the time delay tTrip=5-20 seconds.

Advanced users settings

For advanced users the following parameters need also to be set. Set the length of the trip
pulse to typical tPulse=0.15 sec. Set the blocking time tBlock to block Loss of voltage
check (LOVPTUV, 27), if some but not all voltage are low, to typical 5.0 seconds and set
the time delay for enabling the function after restoration tRestore to 3 - 40 seconds.
IEC 61850 IEC 60617
identification identification
LOVPTUV -
Section 8
Voltage protection
ANSI/IEEE C37.2
device number
27
247