Connection Notes
Overview
The 7XR87 replaces the 3PP1326 voltage divider. The electrical design was changed compared to the 3PP1326
in order to provide additional divider ratios for higher excitation voltages.
The device provides 6 different voltage dividers ordered in 2 groups with 3 dividers each:
•
Divider 1: 10:1, 20:1, and 30:1 for a maximum input voltage of 1000 V DC
•
Divider 2: 40:1, 80:1, and 100:1 for a maximum input voltage of 2000 V DC
A capacitor (C1) provides, in combination with the input resistors, a low pass filter for attenuating the ripple of
the excitation voltage.
The resistor R5 provides the necessary impedance adaptation for using the C-IO-6 of the SIPROTEC 4 7UM6x
protection relay. For the IO210 of the SIPROTEC 5 7UM85, do not connect the resistor R5 (see connection
example below).
[dw_7xr87 connection examples, 1, en_US]
Figure 4-2
7XR87 Connection Example
The excitation voltage has to be connected between GND1 or GND2 and the required divider ratio. Use only 1
voltage divider at once. Also, connect only 1 protection relay at the output.
Connection Data for Terminal C
for a description of the use of each terminal connection.
4.2
4.2.1
4.2.2
7XR87 Voltage Divider for Excitation Voltage
4.2 Connection Notes
SIPROTEC, Coupling Units for Generator Protection, Manual
49
C53000-H5040-C072-1, Edition 09.2018
