Hello everyone, I'm hoping someone can help point me in the right direction here.
I have a 13 slot chassis with a SLC 5/04, 4 IB-16 modules, a DeviceNet Scanner and then 4 OB-16 modules in that order.
My issue is after completing my ladder logic with timers to control multiple outputs I was only getting one output to turn on. I noticed while watching the ladder in Run mode that all my input conditions were on and working as intended but the output would not energize even monitoring the ladder. The controls I needed/used were all on slot 6 output. My output in slot 8 had all my LED's on it. So to test I disabled all rungs in my ladder and left one timer on with a push button input condition to turn on T4:0. With T4:0/EN NO to O:8/10 (green stack light). T4:0/TT NO to O:8/11 (yellow stack light). T4:0/DN NO to O:8/12 (red stack light).
Green light works, yellow and red do not turn on even though the input condition is good. They do however turn on if forced on. That's where I'm getting confused. I swapped output modules with no results. I moved all 3 lights to branches with just the T4:0/EN condition and the same results. I moved yellow to output 15 and it works. I moved the terminal block/wires to slot 9 and changed the ladder to match the new slot and they all work.
If my backplane is bad and the problem, why then do the outputs work when forced on? Is it possible it's the processor instead that's the issue?