Rockwell Automation 1413-ME-PEA Capacitor Bank Controller - Series B - Manual (Page 41)

Publication 1413-UM001C-EN-P - May 2006
Operation 39
• 2 = Retro mode - One CT wired on the A phase and one PT
wired from phases B to C are installed on a three-phase circuit.
The power monitors must be set up in Wye-wiring mode. The
controller swaps the values of the real- and reactive-power data
produced by the power monitors and multiplies them by .
This mode is particularly useful in retrofit applications.
Alarms • Bad Step - This alarm indicates a blown fuse and/or loss of
capacitor condition. The controller measures actual VAR output
from a capacitor step, averages, and compares this value with
the original effective capacitor value. When actual VAR is more
than the user-configurable StepKvarTolerance (default 5%)
below the effective step size for a user-configurable delay
(default 30 seconds), the alarm is activated. The alarm is reset
when actual VAR output is greater than or equal to the setpoint
for the same delay. The step will be latched as tripped/offline if
the VAR output falls below 90% of nominal.
• Target power factor not achieved - If actual power is less than
setpoint for a user-adjustable number of seconds, then set the
alarm flag.
• High and Low Voltage - If BusVolts is outside either limit, this
alarm is activated immediately. After the voltage returns to the
proper range for a configurable amount of time, this alarm is
reset.
• %THD_V above setpoint - If all available steps are added and
%THD_V remains above the setpoint longer than the
configurable time delay, an alarm will be generated and the
system alarm contact closes. The alarm is reset when the
%THD_V falls below setpoint for the same period of time.
• Unbalance - This alarm is set when the average neutral current
exceeds a preset maximum for a configurable period of time. It
is reset using the same timer.
Operator Interface The capacitor bank controller offers three types of operator interface.
• Data access terminal (DAT) – A simplistic operator terminal
physically attached to the controller that provides read/write
access to configuration and operating data. The DAT is provided
with the base unit and all optional configurations.
• Serial PanelView 550 – A comparatively robust operator
interface terminal that provides selectable configuration and
operating screens and a keypad for navigation and data entry.
Communications with the controller is through a serial
point-to-point connection. The serial PanelView is offered in the
Serial HMI option only.
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