User Manual
42 Rockwell Automation Publication 1756-UM540A-EN-P - May 2014
Chapter 2 ControlLogix Isolated Analog I/O Module Features
Module Error at 25 °C (77
°F)
Table 4 lists the 1756-IRT8I module error at 25 °C (77 °F) when using a
thermocouple input type.
Table 4 - 1756-IRT8I Module Error At 25 °C (77 °F) with Thermocouple Input Type
Application
Temperature
Module Error at 25 °C (77 °F) When Connected to Thermocouple Types
Type B Type C Type D Type TXK/
XK(L)
Type R Type S Type E Type J Type K Type N Type T
-200 °C (-328 °F) 1.65 1.79 2.06 2.95 4.53 2.86
0 °C (32 °F) 3.46 4.59 0.93 8.51 8.33 0.77 0.89 1.14 1.72 1.16
200 °C (392 °F) 2.65 2.83 0.71 5.09 5.32 0.61 0.81 1.13 1.36 0.85
400 °C (752 °F) 11.08 2.37 2.36 0.62 4.34 4.70 0.56 0.82 1.07 1.21 0.73
600 °C (1112 °F) 7.56 2.37 2.22 0.56 3.96 4.41 0.56 0.77 1.06 1.16
800 °C (1472 °F) 5.89 2.37 2.20 0.51 3.65 4.14 0.57 0.70 1.10 1.15
1000 °C (1832 °F) 4.93 2.37 2.25 3.40 3.90 0.60 0.76 1.15 1.17
1200 °C (2192 °F) 4.35 2.65 2.36 3.23 3.74 0.79 1.23 1.21
1400 °C (2552 °F) 3.99 2.81 2.47 3.18 3.71 1.33
1600 °C (2912 °F) 3.85 3.00 2.63 3.24 3.80
1800 °C (3272 °F) 3.92 3.46 2.85 3.67 4.36
2000 °C (3632 °F) 3.75 3.19
2200 °C (3992 °F) 4.09 3.95
IMPORTANT
When calculating total measurement error, module error at 25 °C (77 °F) is only
one factor in deriving the total measurement error budget.
Other factors that impact thermocouple measurement error include
the following:
• Thermocouple sensor accuracy/error
• Conditions of thermocouple wire, such as wire length
• Cold junction compensation values