ABB Relion 670 Series Applications Manual page 175

1MRK 511 407-UUS Rev. J
TDn : Time multiplier for inverse time characteristic. This parameter is used for co-ordination
between different inverse time delayed undervoltage protections.
ACrvn , BCrvn , CCrvn , DCrvn , PCrvn : Parameters to set to create programmable under voltage
inverse time characteristic. Description of this can be found in the technical reference manual.
CrvSatn : When the denominator in the expression of the programmable curve is equal to zero the
time delay will be infinity. 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> ·
CrvSatn /100) the used voltage will be: Pickup> · (1.0 + CrvSatn /100). If the programmable
(1.0 +
curve is used, this parameter must be calculated so that:
CrvSatn
×
B
100
EQUATION1448 V1 EN-US
HystAbsn : Absolute hysteresis set in % of VBase . The setting of this parameter is highly
dependent of the application. If the function is used as control for automatic switching of reactive
compensation devices the hysteresis must be set smaller than the voltage change after switching
of the compensation device.
Phasor measurement unit RES670
Application manual
- >
C 0
© Copyright 2017 Hitachi Power Grids. All rights reserved
Section 9
Voltage protection
(Equation 86)
169