Mitsubishi FX2N-48MR, Input changing state electrically but in program no change

[checdw]

Hi everybody, I just started using Mitsubishi PLC and it is a completely new experience, nothing similar to what I am use to (AB), last week I started having a issue on were a adjustment mode was not changing, of course at first we thought it was only the selector, but after checking the electrical section we saw that all of this was correct, even the led indicator of the selector changes status on the expansion module AX2N-16EX-ES. After connecting to the PLC we found that the I (X031) was never changing state on the program run (but you could measure and see even the led change the status), so this is a first to me ever.

At first I thought that maybe the Input was damage so took another Input available and change the address on all the rungs that this X031 was involved, after doing that we tested again with same results, this make us wonder maybe the +24VCD power supply was not working correctly so we decided to install a new power supply, after doing all wiring and checking with the original program, still the same the electrical part changes state from 0 to 24 VCD and the led indicator in the expansion module changes from on to off, but internally on the rung the Input never changes status, I can force the input and it does make the change, but once I remove the force it gets back to the same situation.

Anybody that could offer help?, the second available Input was on another expansion card not even the same.

I am ordering a new cards and even the main controller but have my concerns that there may be another issue.

Sincerely
Edgar C.

 

[shooter]

is the programpart active

 

[checdw]

Shooter,


Yes it is active, the machine was actually working for 3 years now without a issue. I could also see the effect of force the I/O including this part. No one as add anything or move anything on the program, just last 3 week we could connect to the PLC since we didn´t have the communication cable. So I am sure no one touch the program at all. That is why we are baffled at this type of situation.