Hello,
I am new to this forum and need some help. We are measuring resistance with a Dataforth signal conditioner, 0 to 100 ohm input = 0 to 10vdc output. The problem is on the signal conditioner when there is no input resistance on the Dataforth sig cond. the outputs are saturated and actually put out 12.5vdc. The output of the sig cond. is going into a analog input card on a PLC. The card in the PLC is a 0-5vdc input card. We will only be reading about 4.87 ohms on the input of the dataforth card so the output will allways be below 5vdc except when the input to the dataforth card is not hooked up. Is there a way I can limit the voltage that my PLC analog input card see's? would a zener diode work in this application? I just need to make sure my analog input card never see's 5vdc or more. Any help would appreceiated.
Thanks,
Mark