ABB RELION REX640, Руководство по эксплуатации продукта

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Table 128. Rotor earth-fault protection, injection method (MREFPTOC)
Characteristic Value
Operation accuracy Depending on the frequency of the current measured: f
n
±2 Hz
±1.5% of the set value or ±0.002 × I
n
Start time
1)2)
Minimum Typical Maximum
I
Fault
= 1.2 × set
Start value
30 ms 34 ms 38 ms
Reset time <50 ms
Reset ratio Typically 0.96
Retardation time <50 ms
Operate time accuracy ±1.0% of the set value of ±20 ms
Suppression of harmonics -50 dB at f = n × f
n
, where n = 2, 3, 4, 5,…
1) Current before fault = 0.0 × I
n
, f
n
= 50 Hz, earth-fault current with nominal frequency injected from random phase angle, results based on statistical distribution of 1000 measurements
2) Includes the delay of the signal output contact
Table 129. Rotor earth-fault protection, injection method (MREFPTOC) main settings
Parameter Function Value (Range) Step
Operate start value MREFPTOC 0.010...2.000 × I
n
0.001
Alarm start value MREFPTOC 0.010...2.000 × I
n
0.001
Operate delay time MREFPTOC 40...20000 ms 1
Alarm delay time MREFPTOC 40...200000 ms 1
Table 130. High-impedance or flux-balance based differential protection (MHZPDIF)
Characteristic Value
Operation accuracy Depending on the frequency of the measured current: f
n
±2 Hz
±1.5% of the set value or 0.002 × I
n
Start time
1)2) Minimum Typical Maximum
I
Fault
= 2.0 × set
Start Value (one
phase fault)
13 ms 17 ms 21 ms
I
Fault
= 2.0 × set Start Value (three
phases fault)
11 ms 14 ms 17 ms
Reset time <40 ms
Reset ratio Typically 0.96
Retardation time <35 ms
Operate time accuracy in definite time mode ±1.0% of the set value of ±20 ms
1) Measurement mode = “Peak-to-Peak”, current before fault = 0.0 × I
n
, f
n
= 50 Hz, fault current with nominal frequency injected from random phase angle, results based on statistical
distribution of 1000 measurements
2) Includes the delay of the signal output contact
Table 131. High-impedance or flux-balance based differential protection (MHZPDIF) main settings
Parameter Function Value (Range) Step
Operate value MHZPDIF 0.5...50.0 %I
n
0.1
Minimum operate time MHZPDIF 20...300000 ms 10
1MRS759144 A
REX640
Product version: 1
70 ABB