Emerson Micro Motion 2500, Configuration And Use Manual

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• If you set Frequency Output Scaling Method to Frequency=Flow , set Rate Factor
and Frequency Factor.
• If you set Frequency Output Scaling Method to Pulses/Unit , define the number of
pulses that will represent one flow unit.
• If you set Frequency Output Scaling Method to Units/Pulse , define the number of
units that each pulse will indicate.
For all scaling methods, the transmitter puts out a fixed number of pulses per unit,
and at the same time, the Frequency Output signal varies in proportion to flowrate.
Calculate frequency from flow rate
The
Frequency=Flow
option is used to customize the Frequency Output for your application
when you do not know appropriate values for
Units/Pulse
or
Pulses/Unit
.
If you specify Frequency=Flow , you must provide values for Rate Factor and Frequency
Factor:
Rate Factor
The maximum flow rate that you want the Frequency Output to report.
Frequency
Factor
A value calculated as follows:
FrequencyFactor = x N
RateFactor
T
where:
T Factor to convert selected time base to seconds
N Number of pulses per flow unit, as configured in the receiving
device
The resulting Frequency Factor must be within the range of the Frequency Output (0 to
10,000 Hz :
• If Frequency Factor is less than1 Hz, reconfigure the receiving device for a higher
pulses/unit setting.
• If Frequency Factor is greater than 10,000 Hz, reconfigure the receiving device for a
lower pulses/unit setting.
6.3.4 Configure Frequency Output Mode
ProLink III Device Tools > Configuration > I/O > Outputs > Frequency Output
Field Communicator Not available
Overview
Frequency Output Mode defines the relationship between the two Frequency Outputs
(dual-pulse mode).
Integrate the meter with the control system
Configuration and Use Manual 89