Rockwell Automation 1756-CFM ControlLogix Configurable Flowmeter Module - Manual (Page 45)

45 Rockwell Automation Publication 1756-UM010B-EN-P - December 2011
Configurable Flowmeter Module Features and Operational Modes 45
Trigger On
Use Trigger On to determine what flowmeter state triggers the output to
energize. For example, you can configure the CFM module to trigger an
output when the flowmeter reaches a particular frequency (count).
The following events may trigger output 0 when using the flowmeter function:
 Frequency - flowmeter exceeds a certain frequency (count)
 Acceleration - flowmeter accelerates beyond a particular rate
 Prover Run State - flowmeter is operating in the run state
 Prover Range State - flowmeter is enabled and not complete
 Full Flow - flowmeter is in full flow mode
 Trickle Flow - flowmeter is in trickle flow mode
Tie to Counter
Choose which output is connected to which flowmeter input.
Total Overflow
Use Total Overflow to monitor when the total counts has exceeded the
rollover value. The rollover value is a user-defined value set during
configuration. Three events must occur for you to use
this feature:
 Overflow is enabled
 You set a rollover value
 The count total exceeds the rollover value
When the rollover value is exceeded, the Total Overflow bit is toggled to
indicate the event and the Overflow Alarm is set.
Total Overrange
Use Total Overrange to monitor when a flowmeter exceeds the maximum
frequency (100kHz). The maximum frequency period is calculated by the
number of pulses being counted by the CFM per second. When the frequency
period exceeds 100kHz, and the Overrange Alarm is enabled, the Overrange
Alarm is set.