M14964-1 v13
Table 54. Underfrequency protection SAPTOF
Function
Range or Value
Accuracy
Operate value, start function, at
symmetrical three phase
voltage,
StartFrequency
1)
(35.00 - 90.00) Hz
±2.0 mHz
Reset hysteresis
1)
10.0 mHz fixed
±2.0 mHz
Operate time
1)
fr = 50 Hz
Start time measurement with sudden
frequency change
Min. = 175 ms
-
Max. = 195 ms
Start time measurement with
frequency ramp
Min. = 70 ms
Max. = 90 ms
fr = 60 Hz
Start time measurement with sudden
frequency change
Min. = 150 ms
-
Max. = 165 ms
Start time measurement with
frequency ramp
Min. = 60 ms
Max. = 75 ms
Disengaging time
1)
fr = 50 Hz
Start time measurement with sudden
frequency change
Min. = 20 ms
-
Max. = 30 ms
Start time measurement with
frequency ramp
Min. = 75 ms
Max. = 100 ms
fr = 60 Hz
Start time measurement with sudden
frequency change
Min. = 20 ms
-
Max. = 30 ms
Start time measurement with
frequency ramp
Min. = 65 ms
Max. = 90 ms
Operate time delay,
tDelay
1)
fr = 50 Hz
(0.000-60.000)s
±0.2% or ±200 ms
whichever is greater
fr = 60 Hz
±0.2% or ±175 ms
whichever is greater
Note: The stated accuracy is valid for the voltage range 50 V – 250 V secondary.
1)
The settings and test conditions are in accordance with IEC 60255-181 standard (section 6.2 – 6.7).
Line distance protection REL650
1MRK 506 384-BEN H
Version 2.2
74
Hitachi Power Grids
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