Allen-Bradley MicroLogix 1200 User Manual page 14

1-4 Overview
Table 1.2 RTD Accuracy and Temperature Drift
RTD Type
Copper 426 10Ω
Nickel 618 120Ω
Nickel 672 120Ω
Nickel-Iron 518 604Ω
Platinum 385 100Ω
200Ω
500Ω
1000Ω
Platinum 3916 100Ω
200Ω
500Ω
1000Ω
Publication 1762-UM003A-EN-P - February 2003
The tables below provide specifications for RTD accuracy and
temperature drift.
Maximum Scaled Accuracy
(25°C with Calibration)
±0.6°C (1.08°F)
±0.2°C (±0.36°F)
±0.2°C (±0.36°F)
±0.3°C (±0.54°F)
±0.5°C (±0.9°F)
±0.5°C (±0.9°F)
±0.5°C (±0.9°F)
±0.5°C (±0.9°F)
±0.4°C (±0.72°F)
±0.4°C (±0.72°F)
±0.4°C (±0.72°F)
±0.4°C (±0.72°F)
IMPORTANT
Maximum Scaled Accuracy
(0 to 55°C with Calibration)
±1.1°C (1.98°F)
±0.4° C (±0.72°F)
±0.4° C (±0.72°F)
±0.5° C (±0.9°F)
±0.9° C (±1.62°F)
±0.9° C (±1.62°F)
±0.9° C (±1.62°F)
±0.9° C (±1.62°F)
±0.8° C (±1.44°F)
±0.8° C (±1.44°F)
±0.8° C (±1.44°F)
±0.8° C (±1.44°F)
Using Table 1.2 to Calculate Module Accuracy:
For example, when you are using any platinum (385)
RTDs with 0.5 mA excitation current, the module's
accuracy is:
• ±0.5°C (0.9°F) after you apply power to the
module or perform an autocalibration at 25°C
(77°F) ambient, with module operating
temperature at 25°C (77°F).
• ±[0.5°C (0.9°F) ± DT x 0.026 deg./°C
(0.026 deg./°F)] after you apply power to the
module or perform an autocalibration at 25°C
(77°F) ambient, with module operating
temperature between 0 (32°F) and 55°C (131°F).
DT is the temperature difference between the
actual module operating temperature and 25°C
(77°F). The value 0.026 deg./°C (0.026 deg./°F) is
the temperature drift shown in the table above.
• ±0.9°C after you apply power to the module or
perform an autocalibration at 55°C (131°F)
ambient, with module operating temperature at
55°C (131°F).
Maximum Temperature Drift
(from 25°C without
Calibration)
±0.032°C/°C (0.032°F/°F)
±0.012°C/° C (±0.012°F/°F)
±0.012°C/° C (±0.012°F/°F)
±0.015°C/° C (±0.015°F/°F)
±0.026°C/° C (±0.026°F/°F)
±0.026°C/° C (±0.026°F/°F)
±0.026°C/° C (±0.026°F/°F)
±0.026°C/° C (±0.026°F/°F)
±0.023°C/° C (±0.023°F/°F)
±0.023°C/° C (±0.023°F/°F)
±0.023°C/° C (±0.023°F/°F)
±0.023°C/° C (±0.023°F/°F)