RFL Electronics GARD 8000, Инструкция по эксплуатации

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Description of Operation
GARD 8000 Distance Relay RFL Electronics Inc.
When the RMS value drops below the set pick-up value the integrator is reset. Assertion of the output
from the unit requires that the pick-up remains active during the time of the integration; any reset
causes the counter to reset so that a new pick-up starts over counting from zero.
Time overcurrent units include a wide range of operation curves, which can be selected according to
IEC and IEEE/ANSI standards:
ANSI US
•
Moderately Inverse
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Inverse
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Very Inverse
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Extremely Inverse
•
Short Term Inverse
IEC
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Inverse
•
Very Inverse
•
Extremely Inverse
•
Long Term Inverse
•
Short Term Inverse
IEEE
•
Moderately Inverse
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Very Inverse
•
Extremely Inverse
In addition, the RI Inverse
used for coordination with some electromechanical relays.
The time dial setting for all the curves is from 0.05 – 10. However, the following restrictions apply:
•
The IEC curves have a range of 0.05 – 1. If set to a value above 1, it will default to the
maximum setting of 1. The increment is 0.01.
•
All other curves (IEEE, ANSI, RI) have a range of 0.1 – 10. If set to a value below 0.1, it will
default to 0.1. The increment for these curves is 0.1, even though the setting allows steps of
0.01. When set between 0.1 steps, the setting will be rounded to the nearest valid setting. For
example, 2.33 will result in a setting of 2.30 and 2.37 will result in a setting of 2.40.
In addition to the above standard curves, a
User
defined curve can be applied. This curve needs to be
created in the application program ZIVerCOM, saved in a file, and sent to the relay.
There are 4 settings associated with a time overcurrent element; the type of curve, pick-up, time-dial
and Minimum Time delay (or Fixed Time).
When the curve type is selected to Fixed Time, only this setting is applicable.
August 1, 2009 9-38 973.334.3100