CHAPTER 6: SETPOINTS
S2 SYSTEM SETUP
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
6–51
AUX VT RATIO
Range: 1:1 to 5000:1
Default: 1:1
This setting defines the VT primary to secondary turns ratio. For a 14400: 120 VT, the
entry would be “120:1” (14400/120 = 120).
NOTE
NOTE:
The 350 relay can be applied to both metering and protection feeders with up to 65 kV
phase-to-phase voltage. Please ensure that the selected VT ratio and VT secondary do
not result in a primary voltage exceeding 65 kV.
Power system
PATH
:
SETPOINTS > S2 SYSTEM SETUP > POWER SYSTEM
NOMINAL FREQUENCY
Range: 60 Hz, 50 Hz
Default: 60 Hz
Enter the nominal power system frequency. This value is used as a default to set the
optimal digital sampling rate.
SYSTEM ROTATION
Range: ABC, ACB,
Default: ABC
Enter the phase sequence of the power system.
Breaker
The status of the feeder breaker is monitored by the 350 relay using the status of either
one or two contact inputs named 52a (CI#1) and 52b (CI#2) wired to the breaker auxiliary
contacts 52a and 52b respectively (see below).
The following path is available using the keypad. For instructions on how to use the
keypad, please refer to
Chapter 3 - Working with the Keypad
.
PATH
:
SETPOINTS > S2 SYSTEM SETUP > BREAKER
52a CONTACT
Range: Disabled, 52a (CI#1)
Default: Disabled
Select contact input 52a (CI#1) if connected to breaker auxiliary contact 52a.
52b CONTACT
Range: Disabled, 52b (CI#2)
Default: Disabled
Select contact input 52b (CI#2) if connected to breaker auxiliary contact 52b.
BKR CONNECTED
Range: Contact Input 3 to 10, Disabled
Default: Disabled
Select a contact input to show whether the breaker is connected (Racked-in, or
disconnect switches switched-on), or disconnected (racked-out, or disconnect switches
switched-off) to the system.
NOTE
NOTE:
It is highly recommended to monitor the status of the feeder breaker using both breaker
auxiliary contacts 52a, and 52b, however using only one of them is also acceptable.