5-11
Specifications and Reference Data
.
Temperature Effects Example
When using a Pt 100 (
α
= 0.00385) sensor input with a 0 to 100 °C span
at 30 °C ambient temperature, the following statements would be true:
Digital Temp Effects
0.0015 °C
3
[(30 – 20)] = 0.015 °C
D/A Effects
[0.001% of 100]
3
[(30 – 20)] = 0.01 °C
Worst Case Error
D D/A + Digital Temp E D/A Effects = 0.10 °C + 0.02
°C + 0.015 °C + 0.01 °C = 0.145 °C
Total Probable Error
TABLE 5-2. Model 3144 and 3244 Ambient Temperature Effects.
Sensor Options
Digital Accuracy per 1.0 °C (1.8 °F) Change in Ambient
(1)
D/A Effect per 1.0 °C
Change in Ambient
2, 3, or 4 Wire RTDs
Pt 100 (
α
= 0.00385)
0.0015 °C
0.001% of span
Pt 100 (
α
= 0.003916)
0.0015 °C
0.001% of span
Pt 200
0.0023 °C
0.001% of span
Pt 500
0.0015 °C
0.001% of span
Pt 1000
0.0015 °C
0.001% of span
Ni 120
0.0010 °C
0.001% of span
Cu 10
0.015 °C
0.001% of span
NOTE: Using Pt 100 (
α
= 0.003916) and Pt 1000 (
α
= 0.00385) RTDs may require you to update your Model 275 HART Communicator. If you
order the transmitter preconfigured with the new sensor input types, your Model 275 HART Communicator must contain the appropriate
device descriptor in order to establish communications. Refer to Appendix B: Model 275 HART Communicator for more information.
Thermocouples
NIST Type B
0.014 °C if reading
≥
1000 °C
0.029 °C – 0.0021% of (reading – 300) if 300 °C
≤
reading < 1000 °C
0.046 °C – 0.0086% of (reading – 100) if 100 °C
≤
reading < 300 °C
0.001% of span
NIST Type E
0.004 °C + 0.00043% of reading
0.001% of span
NIST Type J
0.004 °C + 0.00029% of reading if reading
≥
0
°C
0.004 °C + 0.0020% of abs. val. reading if reading
<
0
°C
0.001% of span
NIST Type K
0.005 °C + 0.00054% of reading if reading
≥
0
°C
0.005 °C + 0.0020% of abs. val. reading if reading
<
0
°C
0.001% of span
NIST Type N
0.005 °C + 0.00036% of reading
0.001% of span
NIST Type R
0.015 °C if reading
≥
200
°C
0.021 °C – 0.0032% of reading if reading
<
200
°C
0.001% of span
NIST Type S
0.015 °C if reading
≥
200
°C
0.021 °C – 0.0032% of reading if reading
<
200
°C
0.001% of span
NIST Type T
0.005 °C if reading
≥
0
°C
0.005 °C + 0.00036% of abs. val. reading if reading
<
0
°C
0.001% of span
Millivolt Input
0.00025 mV
0.001% of span
2, 3, or 4 Wire Ohm Input
0.007
Ω
0.001% of span
(1) Change in ambient is in reference to the calibration temperature of the transmitter (20 °C [68 °F]) typical from factory.
0.10
2
0.02
2
0.015
2
0.01
2
+
+
+
0.10
°
C
=
