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1MAC050144-MB C
Section 4
Protection functions
615 series ANSI
273
Technical Manual
Figure 129:
Load-shedding operation in the “Freq< AND df/dt>” mode when only the
df/dt condition is satisfied (Rated frequency=50 Hz)
Restore detection
If after the activation of the TRIP input the frequency recovers to a level above the
Restore
pickup Val
setting, the RESTORE
signal
output is activated. The RESTORE output
remains active for a 100 ms. The
Restore mode setting
is used to select the restoring mode
to be "Disabled", "Auto" or "Manual".
60 Hz
Pickup value Freq
set at 0.975 xFn
Pickup value df/dt
set at -0.020 xFn/s
Trip Tm df/dt
= 500ms
Trip Tm Freq
= 1000ms
Load shed mode
= Freq< AND df/dt
58.8 Hz
ST_FRG
OPR_FRG
500ms
1s
TRIP is not activated
in this case as Freq<
condition not satisfied
TRIP
Start of operation timer
Time [s]
Frequency
[Hz]
Summary of Contents for 615 Series ANSI
Page 1: ...Relion Protection and Control 615 series ANSI Technical Manual ...
Page 2: ......
Page 29: ...1MAC050144 MB C Section 615 series ANSI 22 Technical Manual ...
Page 389: ...Section 4 1MAC050144 MB C Protection functions 382 615 series ANSI Technical Manual ...
Page 485: ...Section 6 1MAC050144 MB C Supervision functions 478 615 series ANSI Technical Manual ...
Page 635: ...Section 10 1MAC050144 MB C Other functions 628 615 series ANSI Technical Manual ...
Page 711: ...Section 16 1MAC050144 MB C Glossary 704 615 series ANSI Technical Manual ...
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