Emerson Micro Motion 3711, Configuration And Use Manual, Page: 207 / 234

Configuration and Use Manual 199
Calibration
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B.3 Calibrating the analog output
The analog output is calibrated at the factory to the values shown in Table B-2.
To comply with plant standards, it may be necessary to adjust the AO calibration points.
To adjust the AO calibration points:
1. Attach a meter to the analog output.
2. Select
Configure > I/O > AO Points
.
3. Ensure that Scanning is enabled.
4. To calibrate the output at 4 mA:
a. In the General panel, set the
Value
parameter to
0
.
b. In the Advanced panel, modify the
Adjusted D/A 0%
value until the meter reads
4 mA
.
c. Click
Apply
.
5. To calibrate the output at 20 mA:
a. In the General panel, set the
Value
parameter to
100
.
b. In the Advanced panel, modify the
Adjusted D/A 100%
value until the meter reads
20 mA
.
c. Click
Apply
.
The following formula may be used to assist in determining the correct Adjusted D/A values:
B.4 Density calibration
The Model 3711 system is factory-calibrated for density and does not normally need to be calibrated
in the field. Calibrate the transmitter only if you must do so to meet regulatory requirements.
Note: Micro Motion recommends using meter factors, rather than calibration, to prove the meter
against a regulatory standard or to correct measurement error. Contact Micro Motion before
calibrating your Model 3711 system. For information on meter factors, see Section 5.5.3.
B.4.1 Preparing for calibration
Density calibration includes the following calibration points:
• D1 calibration (low-density)
• D2 calibration (high-density)
D1 and D2 density calibration require a D1 (low-density) fluid and a D2 (high-density) fluid. You
may use air and water.
Both calibrations must be performed without interruption, in the order shown in Figure B-5.
Table B-2 Analog output factory calibration
Output in % D/A counts Output in mA
0 0 4
100 3250 20
AdjustedDANewValue
DesiredmA
ActualmA
----------------------------- AdjustedDACurrentValue
×
=