PLC-5 I/O config table question

Good day all. I have a PLC-5 question with regards to the I/O config table. As I watch the table, it shows me values of my current analog inputs from pressure transducer's. What I would like to know is, why do some of the data fields have a "0" and is highlighted yellow under the "data" column? Thank you

My first guess is that zero is under-range and that the under-range bit for these channels is set as well.

What model of I/O module are you monitoring ?

1771-IFE 5/40E processor

My first guess is that zero is under-range and that the under-range bit for these channels is set as well.

Click to expand...

Ken has it nailed - as usual ...

look at page 117 in your book from the class ... this is exactly the same module that you set up "way back when" ... notice the bits in Word 2 ... those bits become ONEs whenever the input is less than 4 mA, etc. ... in other words, "Data Underrange" ... when those bits are ONEs, the RSLogix5 software displays the field with a yellow highlight ...