A-B 1783-IMS28GNDC Stratix 5410 Ethernet Managed Switches

RTD Error

Module error on the 1756-IR6I module is defined in ohms and is calculated across 

the entire input range that is selected, not the available range of a sensor used with the module. 

For example, if the 1…487  input range is used, the module error is calculated across 507 (actual range = 0.86…507.86 ).

The error in ohms translates to temperature, but that translation varies because the

relationship is non-linear. The most effective way to check a 1756-IR6I module 

error is to calculate the error in ohms and use that value in a linearization table to check the temperatureerror.

If the module is calibrated at operating temperature and the operating temperature remains relatively stable, 

calibration accuracy is better than 0.1% of the full range for the first year after calibration. 

This 0.1% value is a worst case value. In other words, with the 1…487input range that is selected, 

the worst case module error is 0.507.

Finally, you must check an RTD linearization table to determine the temperature error

to which an error of 0.507translates. For example, if the 1756-IR6I has a 0.1% (or 0.507 ) 

error and is operating at 0 °C (32 °F), the temperature error is -1.25…1.2 °C (-2.25…2.16 °F) 

when the Platinum 385 sensor type is used. However, this same ohms error, 

when calculated in an operating temperature of 200 °C (392 °F), translates to a temperature error of -1.4 °C…1.4 °C (-2.52…2.52 °F).