Micro Motion CDM100M, Configuration And Use Manual

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Method Description Setup
Polling The meter polls an external de-
vice for temperature data. This
data will be available in addi-
tion to the internal RTD tem-
perature data. a. Choose Configure > Manual Setup > Measurements > Density > Tem-
perature .
b. Set External Temperature to Enable .
c. Choose Configure > Manual Setup > Inputs/Outputs > External Device
Polling .
d. Choose an unused polling slot.
e. Set
Poll Control to Poll as Primary or Poll as Secondary .
Option Description
Poll as Primary No other HART masters will be on the
network. The Field Communicator is not
a HART master.
Poll as Secondary
Other HART masters will be on the net-
work. The Field Communicator is not a
HART master.
f. Set
External Device Tag
to the HART tag of the external tem-
perature device.
g. Set
Polled Variable
to
Temperature
.
Digital communica-
tions A host writes temperature data
to the meter at appropriate in-
tervals. This data will be availa-
ble in addition to the internal
RTD temperature data. a. Choose Configure > Manual Setup > Measurements > Density > Tem-
perature .
b. Set External Temperature to Enable .
c. Perform the necessary host programming and communica-
tions setup to write temperature data to the meter at appro-
priate intervals.
Postrequisites
To view the current external temperature value, choose
Service Tools
>
Variables
>
External
Variables
. Verify that the value is correct.
Need help? If the value is not correct:
• Ensure that the external device and the meter are using the same measurement unit.
• For polling:
- Verify the wiring between the meter and the external device.
- Verify the HART tag of the external device.
• For digital communications:
- Verify that the host has access to the required data.
- Verify that the host is writing to the correct register in memory, using the correct data
type.
• If necessary, apply an offset.
Configure process measurement
Configuration and Use Manual 33