Ormerod 2 USB Disconnect

I am having problems getting part the early stage of commissioning an Ormerod 2 printer. I can connect to the printer with pronterface and issue commands. I am at the stage where I switch on the hot end. This all works and I can see the temperature reaching 100 degrees. At the point it reaches 100 degrees or soon after, pronterface reports that it cannot read or write to the printer. I have tried the following:-

ensure that the USB cable does not run alongside power leads
tried three different USB cables, the last having double screening and a ferrite block
I have resoldered the USB connector on the Duet board.

After all of that I still get the same problem.

Printer reset does not solve the problem either.

firmware is FIRMWARE_VERSION:1.09 ELECTRONICSuet (+ Extension) DATE:2015-04-21.

Any suggestions what to do next?

Thanks for your help.

Regards

Allan

I have a few suggestions:

1. Check that the screws are tight on the terminal blocks providing 12V power, both on the Duet and on the power regulator board.

2. Use a power distribution block to power the PC and the Ormerod and nothing else. This is to guard against ground transients generated by other mains-powered devices.

3. Try using the web interface instead and disconnect the USB cable. That will tell you whether the problem is specific to using USB comms.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].