Power System; Breaker - GE 350-A9 Instruction Manual

S2 SYSTEM SETUP

Power system

Breaker

NOTE:
NOTE
6–28
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.
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.
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.
The 350 can detect the breaker status by using only one contact: either 52a or 52b.
However, one should be aware that in such cases, it would be impossible to distinguish
between a breaker open state and breaker racked out state, unless another contact from
the breaker is wired to the relay.To clarify this ambiguity, the BKR CONNECTED function
under SETPOINTS/S2 SYSTEM SETUP/S2 BREAKER should be programmed to an additional
contact input. When this additional input is closed, a single 52a or 52b contact will show
both breaker states. When the breaker is racked out, this additional breaker connected
input should be open. In this case, both breaker status indicators will be off.
The logic for Breaker Open, and Breaker Close status is shown in the table below:
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 6: SETPOINTS