GE Multilin 345 Instruction Manual page 201

CHAPTER 6: SETPOINTS
345 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 6-36: Example of an overall breaker alarm from EnerVista
In this example, all eight trigger sources from Logic Element 1 are programmed into an
OR gate, with operands originating from breaker functions such as Breaker Status,
Breaker Health, Trip Counter, Breaker Coil Monitoring, and Breaker Failure. The Trigger
Logic setpoint is selectable to any boolean operator such as OR, AND, NAND, NOR, XOR,
or XNOR. All four block inputs are programmed with contact inputs 1 to 4, and the Block
logic setpoint is programmed into an OR gate. These inputs may include Maintenance
input, Breaker disconnected input, Protection disabled input, etc.
Output Relay # 3 is selected to energize upon operation of Logic Element 1, to denote a
Breaker Alarm. With pickup time delay set to 2000ms, Logic Element 1 (BKR Alarm)
operation will occur 2 seconds after the operation of any of the trigger sources when no
block is applied.
The same logic using Logic Element 2 can be built for Breaker #2.
S4 CONTROLS
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