Check The Overcurrent Block Function; Single Transformer - ABB RER670 Commissioning Manual

Section 10
Testing functionality by secondary injection
10.9.4.6
10.9.4.7
146
condition, the voltage regulation function is not blocked and a lower
command should be issued from the IED.

Check the overcurrent block function

1. Confirm the setting for Iblock in the local HMI under Main menu/
Settings/IED Settings/Control/TransformerVoltageControl(ATCC,91)/
TR1ATCC:x/TR8ATCC:x/TCCtrl/Iblock
2. Confirm the voltage control function response to an applied current above
Iblock, by reviewing the settings in the local HMI under Main menu/
Settings/IED Settings/Control/TransformerVoltageControl(ATCC,91)/
TR1ATCC:x/TR8ATCC:x/OVPartBk. This condition may cause an alarm
or total block of the voltage control function to be displayed on the local
HMI.
3. Inject a current higher than the Iblock setting and confirm the alarm or
blocking condition is present on the local HMI. If an automatic or total
blocking condition occurs, change the applied secondary voltage and confirm
that no tap change commands are issued from the associated binary outputs.
This situation can also be confirmed through reviewing the disturbance and
service reports on the local HMI.

Single transformer

Load drop compensation
1. Confirm that OperationLDC is set to On.
2. Confirm settings for Rline and Xline.
3. Calculate the expected load voltage U
local HMI) based on secondary injection of transformer secondary voltage
(U = USet) and rated load current (I
B
equation 10.
EQUATION2080 V3 EN-US
where:
U , I = Re(I ) + jlm(I
L L L L
When all secondary phase-to-earth voltages are available, use the positive-
sequence components of voltage and current. By separation of real and
imaginary parts:
(displayed as a measured value on the
L
= I1Base), in accordance with
L
) are complex phase quantities
1MRK 506 377-UEN C
SEMOD175185-605 v6
SEMOD175185-669 v2
SEMOD175185-672 v5
(Equation 10)
Railway application RER670 2.2 IEC
Commissioning manual