ABB REL650 Applications Manual page 307

1MRK 506 334-UUS A
Application manual
The setting FreqDiffMax is the maximum slip frequency at which synchronizing is
accepted. 1/FreqDiffMax shows the time for the vector to move 360 degrees, one turn on
the synchronoscope and is called the Beat time A typical value for the FreqDiffMax is
200-250 mHz which gives beat times on 4-5 seconds. Higher values should be avoided as
the two networks normally are regulated to nominal frequency independent of each other
so the frequency difference shall be small.
FreqRateChange
The maximum allowed rate of change for the frequency.
tBreaker
The tBreaker shall be set to match the closing time for the circuit breaker and should also
include the possible auxiliary relays in the closing circuit. It is important to check that no
slow logic components are used in the configuration of the IED as there then can be big
variations in closing time due to those components. Typical setting is 80-150 ms
depending on the breaker closing time.
tClosePulse
Setting for the duration of the breaker close pulse.
tMaxSynch
The tMaxSynch is set to reset the operation of the synchronizing function if the operation
does not take place within this time. The setting must allow for the setting of
FreqDiffMin, which will decide how long it will take maximum to reach phase equality.
At a setting of 10 ms the beat time is 100 seconds and the setting would thus need to be at
least tMinSynch plus 100 seconds. If the network frequencies are expected to be outside
the limits from start a margin needs to be added. Typical setting 600 seconds.
tMinSynch
The tMinSynch is set to limit the minimum time at which synchronizing closing attempt
is given. The synchronizing function will not give a closing command within this time,
from when the synchronizing is started, even if a synchronizing condition is fulfilled.
Typical setting is 200 ms.
Synchrocheck settings
OperationSC
The OperationSC setting Off disables the synchronsim check function and sets the outputs
AUTOSYOK, MANSYOK, TSTAUTSY and TSTMANSY to low.
With the setting Enabled, the function is in service and the output signal depends on the
input conditions.
Section 11
Control
301