UScott
Member
I have a 1771-OFE analog output card that is controlling a VFD and a modulating gas valve on an AMU. The OFE-2 is in a remote rack that uses a 1771 ASB RIO and is controlled by a PLC-5. The problem that I am having is that when I put a value into the BTW, (for example lets say 2048) the BTR for that channel sometimes stays at zero, and sometimes will increase to approx. 1600, and if I am understanding this BTW/BTR thing correctly, they should be the same. The length of my BTW is 5, so I believe that means there is no scaling. In word 5 of the BTR, bits 1,2,and 3 = 1. I believe this means there the channels are recieving invalid data? If anyone has any ideas I would appreciate it, this is my first time dealing with an analog output card. We do have some spare parts in stock so I already tried to change the analog card, the 1771 asb and the power supply. I was told the system was previously working, but I have no way to verify this.