Rockwell 1756-IRT8I

[macg 0]

I'm using three 1756-IRT8I's.  This is a test application.  Of the possible 24 TC inputs, they may use any one of the inputs or only 1.  One TC is required on the first card input 0.  The reset of the points may or may not be used.  I do not see a built in bit that indicates whether or not a TC is connected.  Should I just look at the under range bit?

[Ken Roach 194]

Rockwell usually forces the input data value to its maximum data type value, and sets the Over-Range bit to indicate a disconnected thermocouple.

For example if a thermocouple comes disconnected from my 1734-IT2I, the Over-Range bit is set and the value goes to 32767 instead of my typical 1234 = 123.4 degrees F.

I don't know if that's the case with that specific module, but it's typical.

[macg 0]

Thanks Ken.