Completing The Test - ABB RET670 Commissioning Manual

1MRK 504 154-UUS B
4. Connect all transformers in the parallel group to the same busbar on both the primary and
secondary sides.
5. Set the control mode to
6. Open the test display for Transformer Voltage Control on the LHMI in Main menu/Test/
Function status/Control/TransformerVoltageControl (ATCC, 90).
7. Manually execute Raise commands to step up the tap changer one step for all transformers
in the parallel group
8. Check that the value of
undervoltage blocking level
9. Set the control mode to
The Master in the parallel group will issue a Lower command after time delay t1, which will
also be repeated by the Follower transformers in the group.
10. Set Transformer 2 to Master of the parallel group and T1 to Follower (in that order) and
repeat steps 7 to 10. Undertake this same test by setting each Transformer in turn to Master
11. Note that voltage regulation will be mutually blocked if no transformer is set to Master in the
parallel group. To confirm this function, set T1 as Master and the other transformers in the
parallel grouper set as Follower. Without allocating a new Master, set T1 to Follower and note
the
12. Restore T1 to Master of the parallel transformer group and ensure that control mode for each
transformer is
11.1.5

Completing the test

After the test is completed and relevant disturbance records are saved to document the test, go
to Main menu/Clear on the local HMI and clear all LEDs, the process eventlist and disturbances
from the IED.
Commissioning manual
Manual for each transformer in the parallel control group
BUSVOLT is below overvoltage blocking level OVPartBK and above the
Auto for each transformer in the parallel control group
Automatic block state on the local HMI for all parallel transformers
Automatic .
IEC13000252-1-en.vsd
UVPartBK .
Section 11
Primary injection testing
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