RFL Electronics GARD 8000, Инструкция по эксплуатации

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Description of Operation
GARD 8000 Distance Relay RFL Electronics Inc.
9.6 OPEN POLE LOGIC
The open pole logic detects the opening of any pole of the breaker, generating the corresponding
outputs (A pole open, B pole open and C pole open), based not only on the condition of the breaker
position contacts but also on the output of the three undercurrent detectors, one for each pole, whose
levels are given by the following adjustments: A open pole current level, B open pole current level and
C open pole current level. With the indication outputs of each pole, the open pole detector also
generates the following outputs: ‘one open pole’, ‘three open poles’, or ‘any open pole’.
The outputs of this unit are used by other functions such as pole discrepancy, close-into-fault, and
reclosing.
The type of open pole logic is selected on GARD 8000 under ‘Power Swing Block and Other
Advanced Functions’; ‘Open Pole Selection’.
The setting ‘3 inputs’ allows for individual 52b (or 52a) inputs, one for each phase. The GARD 8000
system logic may however use one 52 input that is mapped to the three phase selective inputs. It is also
possible to use the setting ‘2 inputs’ which allows open pole detection to operate on either one 52b
where the 3 phases are connected in AND or connected in OR.
IA
IB
IC
0
20
A open
52b_A
52b_B
52b_C
B open
C open
1 pole open
3 poles open
Any pole open
Figure 9-28. Open Pole Logic with Individual 52b Inputs
August 1, 2009 9-30 973.334.3100