Proface HMI touch locked up

Working on a model PFXGP4501TAA panel that's been in operation for 5 years. It communicates with a SLC500 over RS232. Today the HMI screens would no longer switch nor the the tocuh cells seemed to work. It locked up while running production.
We tried to power cycle but no change - it stayed locked on main/powerup screen. Also I could not get into the setup menu (pressing opposite corners) which is a bit tricky. Gave up on that quickly thinking locked touch cells would prevent that too. We turned the power off and went to research a new unit in the office. After 15minutes I returned to try entering the setup again. Now the unit worked as before.
This issue is something new to me. The question now is if this will happn again (heat issue, weak component) or if it locked up for another reason (communication to PLC?). Looking for advice...

What type of system is the panel mounted to? What's the earthing and static like? What's the ambient or HMI temperature like?

If it happens again, replace it. You could have it opened up (I assume it's out of warranty), and have it checked for any visible signs of overheating on the internal components, or send it to a repair facility to analyze it... if the price is worth it vs. just moving on to a new unit.

Could be some sort of overheat which caused the unit to fail, and powering it off for a length of time maybe cooled the failed part down enough to work again. Electronics can and will fail over time... the length of time depends on the environment and quality of the components.

If you think it might be communication related, next time it happens, unplug the communication cable to the PLC without powering off, and see if the touch responds after some time.

The touch screen is inside an enclosed small metal box that's mounted on a movable arm. The ground wire on the panel was disconnected - not sure why. The ambient temperature was 80 degrees/high humidity. There's vibration from air cyclinder onthe mchine. It assembles/glues cardboard boxes.
PS. This machine is running daily so the managers won't allow much time for testing and want to order a new HMI. I just have never seen this issue, normally units fault during self check, backlight goes bad, memory loss etc.

ThomasGruetter said:

The ground wire on the panel was disconnected - not sure why.

Click to expand...

Does that mean the whole system is floating on the arm now? If so, earth it again.