ABB REL670 Installation And Commissioning Manual page 143

11.1.2
Control
Parameter
tBreaker
VTConnection
tSyncM
tSyncA
FreqDiffBlock
Testing the frequency difference
The frequency difference is in the example set at 0.20 Hz on the local HMI, and the test should
verify that operation is achieved when the FreqDiffSynch frequency difference is lower than
0.20 Hz. The test procedure below will depend on the settings used.
Procedure
1. Apply voltages U-line = 100% UBase , f-line=50.0 Hz and U-Bus =
100% UBase , f-bus = 50.2 Hz.
2. Check that a closing pulse is submitted and at closing angle less
than 2 degrees from phase equality. Modern test sets will evaluate
this automatically.
3. Repeat with U-Bus = 80% UBase , f-bus=50.25 Hz to verify that the
function does not operate when freqency difference is above limit.
4. Repeat with different frequency differences e.g. 100 mH with f-bus
nominal and line leading and for example 20 mHz (or just above
fSynMin ) to verify that independent of frequency difference the clos-
ing pulse occurs within 2 degrees.
5. Verify that the closing command is not issued when the frequency
difference is less than the set value fSynMin .
Testing the synchronism check
During test of the synchronism check function for a single bay arrangement, these voltage inputs
are used:
U-line UL1, UL2 or UL3 voltage input on the IED.
U-bus U5 voltage input on the IED
Voltage inputs
At test of the synchrocheck function for a 1
puts can be used for the three synchrocheck functions. The voltage is selected by activation of
different inputs in the voltage selection logic:
Verifying settings by secondary
Setting
0.08 s
Line
0 s
0 s
Off
1
/ CB diameter the following alternative voltage in-
2
Chapter 11
injection
135