Allen Bradley Gurus, could use your help 1746-NO4I 4-20/0-10 Question

Hi,
I'm in the field. Long story short... their original devices have failed, and they're not getting the required temperature (analog) data.

I have a spare analog output on the 1746-NO4I, currently it's set up for 4-20ma. The signal they're requesting is a 0-10vdc.
Can I reconfigure this single output on the card to do that? If not, I heard somewhere that the 4-20ma can be converted to a 0-10vdc using resistors... any helpful advice would be greatly appreciated.

Finally, it appears that they're considering swapping out the 4 channel output card with an 8 channel, so they can monitor other temperatures. Can an 8 channel be split up to handle both 4-20 and 0-10?



Thanks!

Your 1746-NO4I will only give you current out. You need a 1746-NO4V for voltage.
You cannot get 0-10V with resistors from 4-20ma. You can get 1-5V with a 250 ohm resistor or 2-10V with a 500 ohm resistor.
There are signal conditioners that will give you a 0-10V output with a 4-20ma input, See link below for one brand, there are many others.

http://www.miinet.com/products/sg_signal.shtml

What 8 point output card are they considering.

You can get a voltage out as Mickey said by placing the volt device in parallel with the resistor which carries the 4-20 ma signal. Ab's tech note says that the 500 ohm resistor be +/- 0.25 ohms in tolerance. This will give you 2-10 volts, not the 0-10 as requested. You might also want to consider an analog in/out card.

Note: you must first do two things. 1. compute if your power supply can carry the load before making the change, and 2. will the card change be supported by your cpu and rack.

regards,
james