Emerson 2200S Manuel D’Utilisation
62
Micro Motion
®
Model 2200S Transmitters
Integrating the Meter with the Control System
6.2.1
Process variable
Table 6-2 lists the process variables that can be assigned to the mA output as the primary variable.
Note: The process variable assigned to the mA output is always the PV (primary variable) defined for
HART communications. You can specify this process variable either by configuring the mA output or
by configuring the PV (see Section 6.3.3). If you change the process variable assigned to the mA
output, the PV assignment is changed automatically, and vice versa.
HART communications. You can specify this process variable either by configuring the mA output or
by configuring the PV (see Section 6.3.3). If you change the process variable assigned to the mA
output, the PV assignment is changed automatically, and vice versa.
Configuration
To configure the mA output process variable:
•
Using the Communicator, select
Detailed Setup > Config Outputs > Channel Setup >
AO Setup
.
•
Using ProLink II, click
ProLink > Configuration > Analog Output
.
•
Using the display, see Figure 2-13.
6.2.2
mA output scale (LRV and URV)
The mA output represents the assigned process variable along a linear scale that ranges from 12 to
20 mA. You must specify:
20 mA. You must specify:
•
The lower range value (LRV) – the value of the process variable that will be represented by a
transmitter output of 12 mA
transmitter output of 12 mA
•
The upper range value (URV) – the value of the process variable that will be represented by a
transmitter output of 20 mA
transmitter output of 20 mA
Note: If the Micro Motion adapter-barrier is installed, the LRV will be represented by a transmitter
output of 12 mA and an adapter-barrier output of 4 mA. The URV is not affected.
output of 12 mA and an adapter-barrier output of 4 mA. The URV is not affected.
Note the following:
•
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.
set to 100.
•
Each process variable has its own LRV and URV. The transmitter stores the site-specified LRV
and URV settings for each process variable. When the process variable assignment is changed,
the LRV and URV are reset to the corresponding stored values. If you change the process
variable assignment, be sure to verify the LRV and URV settings before resuming operation.
and URV settings for each process variable. When the process variable assignment is changed,
the LRV and URV are reset to the corresponding stored values. If you change the process
variable assignment, be sure to verify the LRV and URV settings before resuming operation.
Default LRV and URV settings are listed in Table 6-3.
Table 6-2
mA output process variable options
Process variable
Process variable code
Display
Communicator
ProLink II
Mass flow rate
MFLOW
Mass flo
Mass Flow
Volume flow rate
VFLOW
Vol flo
Vol Flow
Gas standard volume flow rate
GSV F
Gas vol flo
Gas Std Vol Flow
Rate
Rate
Temperature
TEMP
Temp
Temp
Density
DENS
Dens
Density
Drive gain
DGAIN
Drive gain
Drive Gain