Siemens SIPROTEC 4 7SD80, Руководство пользователя

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Ground Fault Differential Protection in Grounded Systems
Pickup Values
Differential current;
87N L: I-DIFF>
Ι
Nom
= 1 A 0.10 A to 20.00 A Increments0.01 A
Ι
Nom
= 5 A
0.50 A to 100.00 A
Operating Times
The operating times depend on the communication speed. The following data require a transmission rate of 512 kbit/s.
Pickup/trip times of the
87N L: I-DIFF>
element at
at 50 Hz or 60 Hz approx.
minimum 35 ms
typical 37 ms
maximum 40 ms
Dropout times of the
87N L: I-DIFF>
element
approx.
minimum 30 ms
typical 32 ms
maximum 34 ms
Differential current 5% of setting value or 1 %
Ι
Nom
Delay of the
87N L: I-DIFF>
element approx. 1 % of setting value or 10 ms
Frequency range 45 Hz to 55 Hz at 50 Hz
55 Hz to 65 Hz at 60 Hz
25 Hz to 45 Hz at 50 Hz
30 Hz to 55 Hz at 60 Hz
Increased tolerances
Time Delays
Tripping delay
87L Trip Delay
0.00 s to 0.10 s Increments0.01 s
Expiry tolerances 1 % of setting value or 10 ms
The set times are pure time delays.
Emergency Operation
Communication failure See section “Time Overcurrent Protection”
Frequency Operating Range
Operating Range 0.8 ≤ f/f
Nom
≤ 1.2
stable at machine startup (f = 0 to f
Nom
)
Standard Precision of Operational Measured Values
The standard accuracy of the operational measured values of the ground fault differential protection of ± 0.5 % of the
rated operational current is ensured up to a transformer error adjustment of 2:1.
4.4
Technical Data
4.4 Ground Fault Differential Protection in Grounded Systems
264 SIPROTEC 4, 7SD80, Manual
E50417-G1100-C474-A2, Edition 02.2018