AI880A IO Error and "Safety Accuracy"
I have got an issue with 3 IO cards (AI880A) installed on one node (1) Other nodes works fine. Once injecting the current greater than 1.575mA the related channel indicates IO Error (channel configured as 0-20mA).
The tests I have already performed.
1. Power supply to L1 and L2 is 25,7V measured.
2. Testing only 2 IOs on one card all other channels disconnected to eliminate interference or etc.
3. Loop injector connected between terminal A15 and B16 (TU834 base). Two loop calibrators used (same results).
4. Shunt Resistors TY801 installed and replaced with new ones.
5. IO module replaced with new one.
6. IO configuration changed from 4-20mA to 0-20mA for troubleshooting. With 4-20mA configuration channel does not work at all.
7. It seems like the "Safety Accuracy" has a greater impact on the threshold level. When set to 5% I am able to go up to 1.575mA however when lowered to 1.9% it already gives IO error on 0.57mA current.