Emerson Micro Motion 2500, Руководство по конфигурации и использованию

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Each concentration matrix is built for a specific density range and a specific
temperature range. If process density or process temperature goes outside the
range, the transmitter will extrapolate concentration values. However, extrapolation
may affect accuracy. Extrapolation alarms are used to notify the operator that
extrapolation is occurring.
a. If necessary, set Matrix Being Configured to the matrix you want to view, and
select Change Matrix.
b. Set Extrapolation Alarm Limit to the point, in percent, at which an extrapolation
alarm will be posted.
c. Enable or disable the high and low limit alarms for temperature and density, as
desired, and select Apply.
Restriction
The high and low limit alarms require the enhanced core processor.
Example: If Extrapolation Alarm Limit is set to 5%, High Extrapolation Limit
(Temperature) is enabled, and the matrix is built for a temperature range of 40 °F to
80 °F, an extrapolation alarm will be posted if process temperature goes above 82 °F
8. Set Temperature Source to the method that the transmitter will use to obtain
temperature data.
Option Description
Poll for external value
(1)
The transmitter will poll an external temperature device, us-
ing HART protocol over the primary mA output.
RTD The transmitter will use the temperature data from the sen-
sor.
Static or Digital Communications
The transmitter will use the temperature value that it reads
from memory.
• Static: The configured value is used. (Not recommen-
ded.)
• Digital Communications: A host writes transmitter data
to transmitter memory.
Note
If the Weights & Measures application is implemented and
the transmitter is secured, digital communications cannot
be used to write temperature or pressure data to the trans-
mitter.
(1) Not available on all transmitters.
9. If you chose
RTD
, no more configuration is required. Select Apply and exit.
10. If you chose to poll for temperature data:
a. Select the Polling Slot to use.
Configure process measurement
52 Micro Motion Model 2500 Transmitters with Configurable Input/Outputs