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Thermocouple resolution – Rockwell Automation 1756-XXXX ControlLogix Analog I/O Modules User Manual

Page 373

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Publication 1756-UM009C-EN-P - December 2010

373

Additional Specification Information Appendix E

Thermocouple Resolution

Thermocouple resolution indicates the degrees that an application
temperature must change before the ControlLogix thermocouple module
reports a change. Resolution varies depending on the these factors.

• Input range used, either:

-12…30 mV

-12…78 mV

• Thermocouple type, any of the following:

B, R, S, E, J, K, N, T, L and D (L and D are used on the
1756-IT6I2 module only)

• Application temperature that is, the temperature of the physical location

where the thermocouple is being used)

EXAMPLE

For example, when the 1756-IT6I module is operating in the
following conditions:

• -12…30 mV input range

• connected to a type K thermocouple

• application temperature of 400 °C (752 °F)

the resolution is 0.017 degrees.

In other words, the application temperature must change by
0.017 degrees or greater for the 1756-IT6I module to record a
change. If the temperature stays in a range from
399.984…400.0169 °C (751.971…752.030 °F), the module will
continue to report an application temperature
of 400 °C (752 °F).