Configure Temperature Compensation Using The Field Communicator - Emerson Micro Motion SGM Series Configuration And Use Manual

Measurement support
Option Description
Polling The meter will poll an external
device for temperature data.
Digital communica- A host writes temperature data
tions to the meter at appropriate in-
tervals.
3.
Postrequisites
If you are using external temperature data, verify the external temperature value displayed
in the Inputs group on the ProLink III main window .
13.2.2 Configure temperature compensation using the
Field Communicator
Temperature compensation adjusts process measurement for the effect of temperature
on the sensor. Temperature compensation is always enabled. You must decide how to
provide temperature data to the meter, then perform the required configuration and
setup.
Prerequisites
If you plan to poll an external device for temperature, ensure that the meter has the
required polling slots available. The meter provides four polling slots, and they may be
already in use. You may need to use a fixed value for some external values. To check the
current polling configuration, choose Configure > Manual Setup > Inputs/Outputs and click
External Device Polling. If you are already polling for temperature, you can use the existing
polled data.
Important
Temperature data is used in several measurements and calculations, for example: gas measurement,
temperature compensation, and base density. For each of these, you can configure the temperature
source. The RTD temperature data is stored separately in device memory. However, if you choose
anything other than RTD, be aware that the fixed value and the polled value are stored in the same
location in device memory. As a result, polled data will overwrite a fixed value.
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If you set up an external temperature:
a. Choose Device Tools > Configuration > I/O > Inputs > External Inputs.
b. In the Line Temperature Input group, check or uncheck the checkboxes as
desired.
If a checkbox is checked, the internal temperature is used for that measurement
or calculation. If a checkbox is unchecked, the external temperature is used.
Setup
a. Set Temperature Source to Poll for External Value.
b. Set Polling Slot to an available slot.
c. Set Polling Control to Poll as Primary or Poll as Secondary.
d. Set External Device Tag to the HART tag of the temperature
device.
a. Set Temperature Source to Fixed Value or Digital Communica-
tions.
b. Perform the necessary host programming and communica-
tions setup to write temperature data to the meter at appro-
priate intervals.
Micro Motion
®
Gas Specific Gravity Meters (SGM)