Testing The Synchrocheck Functionality - Hitachi RET670 Commissioning Manual

1MRK 504 165-UEN Rev. K
UP3LN1
UP3BB1
Testing the frequency difference
The frequency difference test should verify that operation is achieved when the frequency difference
between bus and line is less than set value of FreqDiffMax and above set value of FreqDiffMin. The
test procedure below will depend on the settings used. Input STARTSYN must be activated during
the test.
FreqDiffMax = 50.2 Hz
FreqDiffMin = 50.01 Hz
tBreaker = 0.080 s
1. Apply voltages
1.1. U-Line = 100% UBaseLine and f-Line = 50.0 Hz
1.2. U-Bus = 100% UBaseBus and f-Bus = 50.15Hz
2. Check that a closing pulse is submitted at a closing angle equal to calculated phase angle
value from the formula below. Modern test sets will evaluate this automatically.
Closing Angle = |( (f
f
Bus
f
Line
tBreaker = Set closing time of the breaker
3. Repeat with
3.1. U-Bus = 100% UBaseBus and f-bus = 50.25 Hz, to verify that the function does not
4. Verify that the closing command is not issued when the frequency difference is less than the set
value FreqDiffMin.
11.11.1.2

Testing the synchrocheck functionality

During the test of SESRSYN for a single bay arrangement, these voltage inputs are used:
U-Line
U-Bus
Testing the voltage difference
Set the voltage difference to 0.15 p.u. on the local HMI, and the test should check that operation is
achieved when the voltage difference UDiffSC is lower than 0.15 p.u.
The settings used in the test shall be final settings. The test shall be adapted to site setting values
instead of values in the example below.
Test with no voltage difference between the inputs.
Test with a voltage difference higher than the set UDiffSC.
Transformer protection RET670
Commissioning manual
UL1, UL2 or UL3 line 1 voltage inputs on the IED
Bus1 voltage input on the IED
– f
Bus Line
= Bus frequency
= Line frequency
operate when frequency difference is above limit.
UL1, UL2 or UL3 line 1 voltage input on the IED according to the connection in SMT
Bus voltage input on the IED according to the connection in SMT
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) * tBreaker * 360 degrees) |
Section 11
Testing functionality by secondary injection
M2377-116 v11
M2377-132 v9
M2377-194 v8
231