Monitored Data - ABB Relion Technical Manual

Section 8
Current protection
Table 151: VRPVOC (51V) Non group settings (basic)
Name Values (Range)
GlobalBaseSel 1 - 6
8.10.6
8.10.7
8.10.7.1
8.10.7.2
8.10.7.3
276
Unit Step
- 1

Monitored data

Table 152: VRPVOC (51V) Monitored data
Name Type
IMAX REAL
UUMIN REAL
Operation principle
Measured quantities
The voltage-restrained time overcurrent protection VRPVOC (51V) function is always
connected to three-phase current and three-phase voltage input in the configuration tool
(ACT), but it will always measure the maximum of the three-phase currents and the
minimum of the three phase-to-phase voltages.
Base quantities
GlobalBaseSel: Selects the global base value group used by the function to define (IBase),
(VBase) and (SBase).
IBase shall be entered as rated phase current of the protected object in primary amperes.
VBase shall be entered as rated phase-to-phase voltage of the protected object in primary
kV.
Overcurrent protection
The overcurrent step simply compares the magnitude of the measured current quantity
with the set pickup level. The overcurrent step picks up if the magnitude of the measured
current quantity is bigger than the set level.
Voltage restraint/control feature
The overcurrent protection operation is made dependent of a measured voltage quantity.
This means that the pickup level of the overcurrent step is not constant but decreases with
Default Description
1 Selection of one of the Global Base Value
groups
Values (Range) Unit
- A
- kV
1MRK 502 048-UUS A
Description
Maximum phase current
magnitude
Minimum ph-to-ph voltage
magnitude
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