sparkytex
Lifetime Supporting Member
ok so i go called over to help the instrument mechanics trouble shoot a valve not working. I'm using a PLC 5 and the analog output cards are "1771 NOC A" analog out put cards. the operator has the PID control in manual putting in a manual set point to PD80:5.SO to the valve. It wouldnt change the value no matter what he typed in. so i got the instrument mechanics to remove the wires to the field and sure as all hell the PLC wasnt changing values, it was stuck at 15mA even if i changed the value in I/O config. i could even see the operator changing the value and it was sending out the appropriate mA but still was stuck to 15 mA on the card. So i decided to change to a different output card which had spare address's. So i took the value from PD80:5.SO and inserted a new rung and did a move instruction and used the source as PD80:5.SO then the destination to the new adress N44:34. I had to scale the out put from 0-100 because thats what he uses in the HMI. Everything seems to be working as far as the move i can see it put the data in the new channel but there is nothing coming out of the card! i have hooked up the signal generator and put it into read and nothing. and i know my points are correct on the card. I can see under I/O config under that card and channel its saying its sending out 12 mA at 50. Do you have to enable the analog channel that was not used before after i scaled it? is there some kind of configurating im missing. As of now i have the singal generator hooked up and manually sending signals to the valve with that until i can get this going! PLEASE HELP,
