ABB rec670 Applications Manual

TDn: Time multiplier for inverse time characteristic. This parameter is used for co-
ordination between dif
ferent inverse time delayed undervoltage protections.
ACrvn, BCrvn, CCrvn, DCrvn, PCrvn: Parameters for step n, to set to create
programmable undervoltage inverse time characteristic. Description of this can be
found in the technical reference manual.
CrvSatn: Set tuning parameter for step n. When the denominator in the expression of
the programmable curve is equal to zero, the time delay will be infinite. There will be
an undesired discontinuity. Therefore, a tuning parameter CrvSatn is set to compensate
for this phenomenon. In the voltage interval Pickup> up to Pickup> · (1.0 + CrvSatn/
100) the used voltage will be: Pickup> · (1.0 + CrvSatn/100). If the programmable
curve is used this parameter must be calculated so that:
0
100
CrvSatn
B C× - >
EQUATION1448 V1 EN-US (Equation 95)
HystAbsn: Absolute hysteresis for step n, set in % of VBase. The setting of this
parameter is highly dependent of the application. The hysteresis is used to avoid
oscillations of the PICKUP output signal. This signal resets when the measured voltage
drops below the setting level and leaves the hysteresis area.
Make sure that the set
value for parameter HystABSn is somewhat smaller than the set pickup value.
Otherwise there is a risk that step n will not reset properly.
9.4 Voltage differential protection VDCPTOV (60)
SEMOD153860-1 v2
9.4.1 Identification
SEMOD167723-2 v2
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Voltage differential protection VDCPTOV - 60
9.4.2 Application
SEMOD153893-5 v3
The Voltage dif
ferential protection VDCPTOV (60) functions can be used in some
different applications.
• Voltage unbalance protection for capacitor banks. The voltage on the bus is
supervised with the voltage in the capacitor bank, phase- by phase. Difference
indicates a fault, either short-circuited or open element in the capacitor bank. It is
mainly used on elements with external fuses but can also be used on elements with
Section 9 1MRK 511 401-UUS A
Voltage protection
254 Bay control REC670 2.2 ANSI
Application manual

ABB rec670 Specifications

General

Brand	ABB
Model	rec670
Category	Control Unit
Language	English