Setting Guidelines - ABB REB670 Applications Manual

1MRK 505 337-UUS -
8.4.3
Application manual
mainly used on elements with external fuses but can also be used on elements with
internal fuses instead of a current unbalance protection measuring the current
between the neutrals of two half's of the capacitor bank. The function requires voltage
transformers in all phases of the capacitor bank. Figure
alternative connections of this function.
V1
Vd>L1
V2
Ph C
Ph C
ANSI06000390 V1 EN
Figure 102: Connection of voltage differential protection VDCPTOV (60) function to
detect unbalance in capacitor banks (one phase only is shown)
VDCPTOV (60) function has a block input (BLOCK) where a fuse failure supervision (or
MCB tripped) can be connected to prevent problems if one fuse in the capacitor bank
voltage transformer set has opened and not the other (capacitor voltage is connected to
input V2). It will also ensure that a fuse failure alarm is given instead of a Undervoltage
or Differential voltage alarm and/or tripping.

Setting guidelines

The parameters for the voltage differential function are set via the local HMI or PCM600.
The following settings are done for the voltage differential function.
Single grounded wye
Ph B
Vd>A
V1 V2
Ph B Ph C
en06000390_ansi.vsd
Section 8
Voltage protection
102 shows some different
Double wye
Ph B
245