Hi
Recently experienced a sudden fault - USB connectivity failed. I have checked the PC end and the USB cable and all PC ports are fine - the problem lies with the printer. In addition I have had some weird issues with temperature reporting on the LCD screen. On occasion it will say Heated Bed = NA ?? restarting the machine usually clears the problem (which seems to be random). Also on-screen heated bed temperature readout umps around - not steady like it used to be. Can anybody assist??
If you have not already, I would take the bottom off the printer and make sure all physical connections are seated properly. Maybe to the point of unplugging and replugging everything? Also do this for the connection at the back of the build platform. If that does not work I would start to suspect a hardware issue w the mother board.
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Hi,
Perhaps… I had an identical (USB) problem, in that printer/USB/PC worked fine, then nothing. Like you, I swapped cables, checked PC ports, in the end (after sticking a scope onto the USB lines from the printer), I discovered it was the printer.
The problem, the small RS232 to USB IC on the main PCB (I forget the specific name). Apparently it is a sensitive device (I was operating an electric drill in the area at the time, maybe a power surge destroyed it). Anyway, I ended up buying a new main PCB.
As for the NA message, it sounds like an intermittent connection (wire to pin, pin to connector, etc…). Start at the heater board and work back checking every connection until you get to the main PCB (if it comes to that).
Regards
Phil
Thanks for your responses - Technology Outlet are sending a replacement MB which should sort the problems out. Thoroughly recommend Technology Outlet - first class service.
I think I’ve gotten to the bottom of this one, measure the voltage from the outside of the USB (ground) on your PC to the USB (ground) on the Wanhao. I found mine was 120V AC (make sure to do an AC not DC measurement).
Also I noticed getting a small shock sometimes from the outside of the case.
I tested all earths inside the Box and they are fine, everthing is OK, so the only thing I can think of is that the power supply within the Wanhao has a path from neutral to ground.
Also when you start connecting the PC to USB or ground the USB in anyway, then the screen on the front can go quite corrupt until you change the menu.
I’m going to try mounting the power supply so the case doesn’t touch (via metal) the base plate, then if it still doesn’t work I might try disconnecting ground from the power supply all together, and making sure the USB connector is grounded (which it currently isn’t).
When I switch the power off to the printer I don’t get the 120V AC differential before anybody asks.
