Setting Guidelines - ABB RELION RET670 Applications Manual

Section 10
Voltage protection
10.5.3
634
Fuse failure supervision (SDDRFUF) function for voltage transformers. In many
application the voltages of two fuse groups of the same voltage transformer or fuse
groups of two separate voltage transformers measuring the same voltage can be
supervised with this function. It will be an alternative for example, generator units
where often two voltage transformers are supplied for measurement and excitation
equipment.
The application to supervise the voltage on two voltage transformers in the generator
circuit is shown in figure 300.
V1
Vd>
v2
Gen
en06000389_ansi.vsd
ANSI06000389 V1 EN-US
Figure 300: Supervision of fuses on generator circuit voltage transformers

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.
Operation: Off/On
GlobalBaseSel: Selects the global base value group used by the function to define
IBase, VBase and SBase as applicable.
BlkDiffAtVLow: The setting is to block the function when the voltages in the phases are
low.
To Protection
To Excitation
1MRK 504 163-UUS A
Transformer protection RET670 2.2 ANSI
Application manual
SEMOD153915-5 v3