HMI Communication with PLC loss

[plambert]

Hi 

I have a problem which I can't figured it out. I have a project with and HMI GTO2310 and a plc TM251MESE and everything is working fine and communication is ok. For some reason there appears to be a communication lost or time out that occurs randomly... It happened a couple of times now and i don't find out why. Like for instance I was doing the final testing yesterday everything is good, came back this morning and no more variables on the screens and the buttons don't work anymore. There is no triangle beside the variables or no message that tells me that the communication with the PLC is lost. Nothing except empty variables...and nothing working. When opening machine expert gateway I can see the plc but not the HMI anymore, however if I ping it it does respond.... If I download into the HMI using USB it will start to communicate again with the PLC and i will see the HMI in the gateway but for how long... it could last a day...2 it is random that it loose communication and so far it always happened when I am out of the office and not working on my project...Did somebody had the same problem? Could it be a timeout communication error but why??? Please advise if you have some solution, waiting to correct this before going on my startup.