Ethernet connection to Mesa 7i76e disconnecting on its own after one minute

 

Did you try another LAN cable?
Is the machine and the PC grounded properly?
Use a DVM and measure between Mesa 24V GND and machine case, in AC mode, while the machine is ON, post result.

I did not try another LAN cable.
The machine and PC are grounded properly.
I dont have a DVM at the moment but as soon as I get one I will measure those.
I believe this is a software issue because even with qtplasmac not running I get the disconnected error every 45 seconds
 

Can you power off the machine and leave only Mesa powered?

I had a problem with a Mesa board disconnecting a couple years ago.

Turned out it was a bad/weak DC-DC power supply.  Voltage would drop intermittently, causing the Mesa to reset and I'd get the 'error finishing read' nightmare.  Looked like a network issue, but @PCW helped me diagnose it as a power problem.

Maybe double-check whatever is powering the Mesa and see if it's dodgy.

Also make sure all power management is disabled on the host PC
Similar issues can come from Ethernet (EEE) or PCIE power management