2-20 Installation Date Code 20001006
SEL-351 Instruction Manual
1. Voltage Channel VS does not need to be connected. It is used only in voltage and synchronism check elements
and voltage metering.
2. In this example, current Channel IN provides current polarization for a directional element used to control ground
overcurrent elements. Separate from Channel IN, the residual ground overcurrent elements operate from the
internally derived residual current I
G
(I
G
= 3I
0
= I
A
+ I
B
+ I
C
).
Figure 2.10: SEL-351 Relay Provides Directional Overcurrent Protection and Reclosing for
a Transmission Line (Current-Polarization Source Connected to Channel IN)
Courtesy of NationalSwitchgear.com
To Next Page
Loading...
