You must be able to take a sample of your process fluid and obtain a laboratory concentration value at line
density and line temperature.
Procedure
1. Take a concentration reading from the meter, and record line density and line temperature.
2. Take a sample of the process fluid and obtain a laboratory value for concentration at line density and
line temperature, in the units used by the meter.
3. Subtract the meter value from the laboratory value.
4. Enter the result as the trim offset.
•
Using the display: Choose
Menu
>
Configuration
>
Process Measurement
>
Concentration
Measurement
>
Configure Matrix
, select your matrix, and enter
Trim Offset
.
•
Using ProLink III: Choose
Device Tools
>
Configuration
>
Process Measurement
>
Concentration
Measurement
, set
Matrix Being Configured
to your matrix, and enter
Trim Offset
.
•
Using the Field Communicator: Choose
Configure
>
Manual Setup
>
Measurements
>
Optional
Setup
>
Conc Measurement
>
Configure Matrix
and set
Matrix Being Configured
to your matrix.
Then choose
Service Tools
>
Maintenance
>
Calibration
>
Trim CM Process Variables
and enter
Concentration Offset
.
5. Take another concentration reading from the meter, and compare it to the laboratory value.
•
If the two values are acceptably close, the trim is complete.
•
If the two values are not acceptably close, repeat this procedure.
Calculating the trim offset
Laboratory value
64.21 °Brix
Meter value
64.93 °Brix
64.21 − 64.93 = −0.72
Concentration offset:
−
0.72
14.8 Adjust concentration measurement with Trim Slope
and Trim Offset
Trim Slope
and
Trim Offset
adjust the meter's concentration measurement to match a reference value.
Tip
You can adjust concentration measurement by applying the trim offset only, or by applying both the trim
offset and the trim slope. For most applications, the trim offset is sufficient.
Prerequisites
Ensure that the active matrix is the one that you want to trim. You can set the offset and slope separately for
each matrix on your transmitter.
You must be able to take measurements of your process fluid at two different concentrations.
You must be able to take a sample of your process fluid at each of these concentrations.
Measurement support
Configuration and Use Manual
March 2019
MMI-20025166
222
Micro Motion Model 5700 Transmitters with Configurable Outputs