Completing The Test - ABB ret650 Commissioning Manual

Section 6
Testing functionality
6.7.1.8
74
1. Confirm that OperationPAR is set to CC for each transformer in the parallel
group.
2. Confirm that OperCCBlock is set to On for each transformer in the parallel
group.
3. Review the setting for CircCurrLimit.
4. Review the setting for CircCurrBk to confirm whether a circulating current
limit will result in an Alarm state, Auto Block or Auto&Man Block of the
automatic voltage control for tap changer, for parallel control function
TR8ATCC.
5. Inject a voltage UB equal to USet for each transformer.
6. Inject a load current for Transformer 1 that is equal to rated load current
IBase (for winding 2, which is defined in a global base function, selected with
setting GlobalBaseSel2 for TR8ATCC) and a load current for Transformer 2
that is 1% less than (IBase – (IBase · CircCurrLimit))
7. Confirm that the automatic voltage control for tap changer, for parallel
control function TR8ATCC responds in accordance with the setting for
CircCurrBk. Alarm and blocking conditions can be confirmed through
interrogation of the event menu or the control menu on the local HMI.
VTmismatch during parallel operation
1. Confirm that OperationPAR is set to MF for each transformer in the parallel
group.
2. Review the setting for VTmismatch and tVTmismatch.
3. Inject a voltage UB equal to USet for Transformer 1 and a voltage less than
(USet – (VTmismatch · USet)) for Transformer 2.
4. This condition should result in a VTmismatch which will mutually block the
operation of the automatic voltage control for tap changer, parallel control
function TR8ATCC for all transformers connected in the parallel group,
which can be confirmed through interrogation of the local HMI.
5. Confirm that the automatic voltage control for tap changer, parallel control
function TR8ATCC responds in accordance with the setting for CircCurrBk.

Completing the test

Continue to test another function or end the testing by setting the parameter
TestMode to Off under Main menu/Tests/IED test mode/1:TESTMODE. If
another function is tested, then set the parameter Blocked to No under Main menu/
Tests/Function test modes/Control/TR8ATCC(90)/X:TR8ATCC for the
function, or for each individual function in a chain, to be tested next. Remember to
set the parameter Blocked to Yes, for each individual function that has been tested.
1MRK 504 126-UEN -
Commissioning Manual