Sync1 - ABB REX 521 Technical Reference Manual, Standard Configurations

1MRS 751802-MUM
7.1.13.
Protection Relay
Technical Reference Manual, Standard Configurations
f1
f<
f>
df/dt<
df/dt>
BS1 START1
BS2 TRIP1
GROUP START2
RESET TRIP2
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System frequency protection, f1 and f2
Voltage limit
Start frequency
Operate time 1
Start df/dt
Operate time 2
Operation mode
Operation accuracy
Start time
Reset time
Operate time accuracy

SYNC1

The function block is designed to be used for checking the conditions for circuit-
breaker closing. The function can be used for closing ring mains, interconnecting
busbars and connecting generators to the network. The harmonics are suppressed.
f2
f<
f>
df/dt<
df/dt>
BS1 START1
BS2 TRIP1
GROUP START2
RESET TRIP2
0.30...0.90 x Un
25.00...75.00 Hz
0.10...120.00 s
0.2...10.0 Hz/s
0.12...120.00 s
Not in use
f</f> 1 timer
f</f> 2 timers
f</f> OR df/dt>
f</f>AND df/dt>
f</f> OR df/dt<
f</f>AND df/dt<
Accuracy for the f</f> function is defined in the setting
range 25...75 Hz.
Frequency function (f</f>): ± 0 mHz
Frequency rate of change function (df/dt):
real df/dt < ± 5 Hz/s: accuracy ±100 mHz/s
real df/dt < ± 15 Hz/s: accuracy ±2.0% of the real df/dt
Undervoltage blocking: ±1.0% of set value
Total start times at rated freq. fn = 50 Hz:
Frequency measurement: < 100 ms
Df/dt measurement: < 120 ms
Note! The operate times and start times are specified for
the set rated frequencies 50 Hz and 60 Hz.
140...1000 ms
(Depends on the minimum pulse width set
for the trip output)
±2.0% of set value or ±30 ms
REX 521
89