118
Reference Manual
00809-0100-4021, Rev JA
HART Commissioning
April 2017
HART Commissioning
1. Determine the required performance.
2. Calculate total probable error.
a. Digital accuracy = °C
b. D/A accuracy = (% of transmitter span)
(ambient temperature change) °C
c. Digital temp effects = (°C per 1.0 °C change in ambient temperature)
(ambient temperature
change)
d. D/A effects = (% of span per 1.0 °C) x (ambient temperature change)
(Process temperature
range)
e. Sensor accuracy = °C
f.
3. Calculate stability per month.
(% per months)
(process temperature range)
4. Calculate Calibration Frequency.
Example for Rosemount 3144P Pt 100 (
α
= 0.00385)
Reference temperature is 20 °F
Process temperature change is 0–100 °C
Ambient temperature is 30 °C
1. Required performance: ± 0.35 °C
2. TPE = 0.102 °C
a. Digital Accuracy = 0.10 °C
b. D/A Accuracy = (0.02%)
(30 – 20) °C = ±0.002 °C
c. Digital Temperature Effects = (0.0015 °C/°C)
(30–20) °C = 0.015 °C
d. D/A effect = (0.001%/°C)
(100 °C) x (30–20) °C = 00.01 °C
e. Sensor accuracy = ± 0.420 °C at 400 °C for a class A RTD sensor with CVD constants
f. TPE =
3. Stability per month: (0.25%/60 months)
(100 °C) = 0.00416 °C
4. Calibration frequency:
3.16
Trim the transmitter
The trim functions should not be confused with the rerange functions. Although the rerange command
matches a sensor input to a 4–20 mA output—as in conventional calibration—it does not affect the
transmitter’s interpretation of the input.
One or more of the trim functions may be used when calibrating. The trim functions are as follows:
Sensor input trim
Transmitter-sensor matching
Output trim
Output scaled trim
TPE
DigitalAccuracy
(
)
2
D/A
(
)
2
DigitalTempEffects
(
)
2
D/A
Effects
(
)
2
SensorAccuracy
(
)
2
+
+
+
+
=
CalFreq
RequiredPerformance TPE
–
(
)
StabilityPerMonth
-----------------------------------------------------------------------------------------
=
0.102
(
)
0.0022
0.0152
0.012
0.4202
)
+
+
+
+
= 0.102 °C
2
2
2
2
2
0.35 0.102
–
0.00416
---------------------------------
= 60 months (5 years)
Summary of Contents for Rosemount 3144P
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Page 10: ...8 Reference Manual 00809 0100 4021 Rev JA Title Page April 2017 Title Page ...
Page 16: ...6 Reference Manual 00809 0100 4021 Rev JA Introduction April 2017 Introduction ...
Page 38: ...28 Reference Manual 00809 0100 4021 Rev JA Installation April 2017 Installation ...
Page 235: ...225 Reference Manual 00809 0100 4021 Rev JA April 2017 ...
