Rockwell Automation 1407-CGCM Combination Generator Control Module User Manual
Page 96
96
Rockwell Automation Publication 1407-UM001G-EN-P - April 2013
Chapter 4
CGCM Unit Configuration
• Acceptance Delay - Establishes the time that all sync parameters must be
continuously within their respective acceptance windows to permit closing
the breaker. The Configuration table tag SynchAcceptDly stores this
value, expressed in seconds.
Bus A Offsets
• Voltage multiplier - Establishes a factor by which the Bus A voltage is
scaled during synchronization. It can be used to compensate for
transformer ratio differences between the generator and bus voltages. For
example, if the generator nominal voltage is 4160V and the nominal Bus A
voltage is 12,480V (each measured line-to-line), a voltage multiplier value
of 0.333 permits voltage matching during synchronization. Configuration
table tag BusA_V_Scaler stores this parameter.
• Phase - Establishes an offset angle added to the measured Bus A phase
angle. It can be used to compensate for phase shift across transformers or
between delta and wye connected systems.
As an example, consider the system shown in
Connection for Four-wire Wye Bus and Two (or three) Transformer Delta
Generator System
When a generator with three-wire (delta) metering is synchronized to a
bus with four-wire (wye) metering, set the phase offset to 30° to
compensate for the 30° lag between the delta and wye systems.
Configuration table tag BusA_PhOffset stores this parameter, expressed
in degrees.
Bus B Offsets
• Voltage multiplier - Establishes a factor by which the Bus B voltage is
scaled during synchronization. It can be used to compensate for
transformer ratio differences between the generator and bus voltages.
Configuration table tag BusB_V_Scaler stores this parameter.
• Phase - Establishes an offset angle added to the measured Bus B phase
angle. It can be used to compensate for phase shift across transformers or
between delta and wye connected systems. Configuration table tag
BusB_PhOffset
stores this parameter, expressed in degrees.
TIP
The Bus A examples also apply to Bus B.