Rockwell Automation 1407-CGCM Combination Generator Control Module - Manual (Page 80)

80 Rockwell Automation Publication 1407-UM001G-EN-P - April 2013
Chapter 4 CGCM Unit Configuration
• Soft Start Time - The desired time to ramp up from the Soft Start Initial
Voltage to the nominal generator output voltage. This parameter is stored
in tag SoftStartTime in the Configuration table and is expressed in
seconds.
• Over-excitation Voltage Setpoint - Establishes the over-excitation voltage
setpoint used by the CGCM unit. This setpoint is stored in tag
OvrExcV_Setpt
in the configuration table and scaled in volts.
• Over-excitation Time Delay - Establishes the time to annunciate a fault
once the over-excitation voltage setpoint has been exceeded. This setpoint
is stored in tag OvrExcV_TimeDly in the configuration table and scaled
in seconds.
• Loss of Excitation Current Setpoint - Establishes the level of excitation
current that is considered to be a minimum needed to maintain generator
synchronization when in parallel with other power sources such as a utility
grid. This setpoint is stored in tag LossExc_I_Setpt in the configuration
table and scaled in amperes. Excitation current in excess of the loss of
excitation current setpoint enables loss of sensing protection.
• Loss of Excitation Current Delay - Establishes the amount of time in
seconds that the excitation current must be continually below the Loss of
Excitation Current Setpoint before the CGCM unit annunciates a loss of
excitation fault. This setpoint is stored in tag LossExc_I_TimeDly in the
configuration table
• Rotating Diode Fault Main Pole - Indicates the number of poles of the
main field of the generator. Stored in tag MainPole in the configuration
table.
• Rotating Diode Fault Exciter Pole – Indicates the number of poles of the
exciter field of the generator. Stored in tag ExciterPole in the
configuration table.
• Rotating Diode Fault Open Diode Level - Establishes the percent ripple at
which the rotating diode monitor alarm turns on when an open diode
condition occurs. This parameter is stored in tag
OpenDiodeMonitorLevel
in the configuration table and is expressed in
percent of maximum ripple current.
• Rotating Diode Fault Shorted Diode Level - Establishes the percent ripple
at which the rotating diode monitor alarm turns on in the event a shorted
diode condition occurs. Tag ShortedDiodeMonitorLevel in the
configuration table stores this value, expressed in percent of maximum
ripple current.
TIP
Coordinate the Over-excitation voltage setpoint and time delay
settings with the OEL function settings to protect the exciter from
overheating while avoiding nuisance tripping from normal field
forcing during transient conditions.