Outputs; Output Relays - GE 845 Instruction Manual

CHAPTER 4: SETPOINTS

Outputs

Output Relays

845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 4-51: Outputs Display Hierarchy
The 845 relay is equipped with a number of Auxiliary Relays, starting with Aux. Relay 1. The
I/O cards, and a number of auxiliary output relays are defined at the time of relay ordering.
The Auxiliary Relays can be energized from the menu of the protection or control feature or
from their respective menus when assigning a FlexLogic operand (trigger) under the
setpoint "Aux Rly # Operate".
The Auxiliary Relays can be used for different applications. Any output relays from 845 can
be programmed for either tripping and closing a breaker. For each of the two or three
breakers, the user can select a pair of Auxiliary Relays for tripping and closing. Depending
on how an Aux. Relay is assigned, one of the following logic diagrams apply:
1. If the auxiliary output relay is programmed under the Breaker menu for breaker
tripping, the operation of the output follows the Trip logic outlined in the Relay 1 "TRIP"
logic diagram below.
2. If the auxiliary output relay is programmed under Breaker menu for breaker closing,
the operation of the output follows the "Close" logic diagram below.
3. If the auxiliary output is not programmed for tripping or closing a breaker, the
operation of the output follows the generic relay logic from Auxiliary Relays generic
logic diagram below.
The Trip and Close selected auxiliary relays will follow the respective Trip and Close logic,
meaning they will have fixed operating characteristics as they depend on breaker
feedback for resetting.
The selected aux relays for breaker tripping, are also available for selection from the
menus of all protection elements.
The selected aux relays for breaker closing, are excluded from the list for selection from
the menu of all elements. Refer to breaker setup section on how to select auxiliary relay for
breaker trip and close.
OUTPUTS
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