ABB TCC300, User Manual, Page: 533 / 716

Table 65: Power Direction Bias settings
Setting Description
None When the Power Direction Bias function is set to
"None", the control applies an 8 mA hysteresis band
with a bandcenter of 0 load current (+4 mA to –4 mA)
to switch between forward and reverse power. The
control will switch from forward power to reverse
power when the load current exceeds –4 mA
(reverse direction). The control will switch from
reverse power to forward power when the load
current e4 mA (forward direction).
Forward Bias When the Power Direction Bias function is set to
"Forward Bias", the control applies a 0 mA to –4 mA
hysteresis band to switch between forward and
reverse power. The control will switch from reverse
power to forward power when load current is > 0 mA
(forward direction). The control will switch from
forward power to reverse power when the load
current exceeds –4 mA (reverse direction).
Reverse Bias When the Power Direction Bias function is set to
"Reverse Bias", the control applies a 0 mA to +4 mA
hysteresis band to switch between forward and
reverse power. The control will switch from forward
power to reverse power when load current is < 0 mA
(reverse direction). The control will switch from
reverse power to forward power when the load
current e4 mA (forward direction).
Reverse Power Operation Mode
Upon detection of power reversal, after a 5 second delay, the control will operate in the
selected mode. The operating mode is selected from the following options:
Block – Inhibits automatic tapchange operation. This locks the tapchanger on the tap
position in use at the time reverse power flow is detected. It is the recommended setting
for independent power producers or in situations when reverse power flow is not expected.
The control will revert to normal operation when forward power flow resumes.
Regulate Forward (Ignore) – The control will take no different action than in the forward
direction. It essentially does not use the power direction in the control decisions. This is
the same as a control which does not have power direction knowledge.
Regulate Reverse and Regulate Reverse Measured –The control will detect reverse
power flow and regulate according to reverse power settings as selected in the Setpoint
Menu. With tap position knowledge, the control calculates the source-side potential
without the use of a source side VT. This feature is designed for use with feeder voltage
regulators which continue to operate in a radial mode after system switching causes the
power flow reversal.
1VAC388793-MB A
Section 7
Setpoints
TCC300 527
User Manual