Required Transmitter Configuration
4.5.1Configuring the primary variable
The primary variable is the process variable to be reported through the mA output. Table
Table 4-7 mA output process variable assignments
Process variable | ProLink II label |
|
|
Mass flow | Mass Flow Rate |
|
|
Volume flow | Volume Flow Rate |
|
|
Note: The process variable assigned to the mA output is always the PV (primary variable).
4.5.2Configuring the mA output range (LRV and URV)
The mA output uses a range of 4 to 20 mA to represent the assigned process variable. You must specify:
•The lower range value (LRV) – the value of the process variable that will be indicated when the mA output produces 4 mA
•The upper range value (URV) – the value of the process variable that will be indicated when the mA output produces 20 mA
Enter values in the measurement units that are configured for the assigned process variable (see Section 4.4).
Note: The URV can be set below the LRV; for example, the URV can be set to 0 and the LRV can be set to 100.
4.5.3Configuring the AO cutoff
The AO (analog output) cutoff specifies the lowest mass flow or volume flow value that will be reported through the mA output. Any mass flow or volume flow values below the AO cutoff will be reported as zero.
Note: For most applications, the default AO cutoff is used. Contact Micro Motion customer support before changing the AO cutoff.
Multiple cutoffs
Cutoffs can also be configured for the mass flow and volume flow process variables (see Section 6.5). If mass flow or volume flow has been assigned to the mA output, a
Example | Configuration: |
| • mA output: Mass flow |
| • AO cutoff: 10 g/sec |
| • Mass flow cutoff: 15 g/sec |
| As a result, if the mass flow rate drops below 15 g/sec, the mA output |
| will report zero flow. |
|
|
24 | Micro Motion® Model 1500 Transmitters with the Filling and Dosing Application |
