Trying to get going again


My K8200 was working fine however I didn’t use it for the summer. Coming back to it, I couldn’t get it to respond. I have reinstalled the software and drivers using the download on the Velleman site. I have found a Com port that allows me to connect but when I select manual control I cannot get a response from the motors. I can control the heaters and the fan. I have a flashing red and green LED by the USB socket. When i try to control x, y or z manually I get an OK then “printer stopped due to errors fix errors then use M999 to restart”
I noticed that looking at the Eprom setting under configuration, everything is set to zero- is that correct.

Any ideas?

M999 indicates there is a problem with the temp of the nozzle or the bed.
If you look at the software while connected under manual control both should be reading room temp.
If one of them are at 0C you have an open on that thermistor if they are reading 700 or greater you have a short on that thermistor. in the printer settings make sure “Reset on Connect = Disabled”

Hi Wrong Way,

Both bed and nozzle show 0/50 and 0/190 in the line at the bottom of the screen so I guess I have an “open” on both however I did set the reset command as suggested. Can you advise as to what I need to do next?



If they are both showing 0C it sounds like the printer is not getting power.
Check for 15 volts at the blue connector on the control board.
Also check Therm1 (hot end) and Therm 2 (bed) make sure they are plugged into the control board.
Both are at the top of the board.
You will need to enable the Eprom in the firmware.
I don’t remember where you need to do that

Hi Wrong Way,

i am back at it again. i did find that when I reinstalled, I hadn’t unzipped the file with the drivers. That is done and I get a response to the XYZ home commands but not the individual step buttons. Nevertheless there appears to be power and a quick check with my meter confirms this.
i have the bed stuck at room temperature (if I activate the fan, it does drop) and the nozzle at zero. Swapping the plugs at the top of the board switches the reading.

Using the config tab, I restored the eprom factory settings . reset on connect is disabled in printer settings.

Any ideas?


I think after some prodding I have a thermistor hardware issue-I will get back to you with the result.


What is the temp for the extruder and the bed say in the software?

Back at it- the temperature at the bed is room temperature and the head is zero. I am going to change the heater and the thermocouple at the head and tidy up my soldering on the bed to eliminate possible problems there.


The problem is in the thermistor of the print head (there is an open)
To test the board swap therm 1 and therm 2 in the software the print head should show room temp and the bed should be 0C if this happens the board is OK and the problem in in the wiring or the thermistor has been damaged.


i finally got around to this- changing the thermocouple did sort the problem.
Many thanks!


Glad to hear its working again.


Back at it a year later: I need to print some small parts for a 40 year old Landrover and I have a dead printer

I see the LEDs flashing at LD5&6 when I plug in the USB then a green one at what might say JPV when I press reset. I have reinstalled the software and the printer appears to connect. Selecting manual control and turning on the heaters has no result-nothing appears on the temperature graphs and the manual control has no response.
I have tried different Baud rates, but its no go. Help!


What kind of messages do you get in the printer console?

Do you have the LCD display on the printer? If so, does it display a non-zero target temperature for the extruder and/or bed heaters? Does it display a “room temperature” reading from the sensors, or some other value?

If in doubt, please post some screenshots and/or pictures of the LCD.

Hi, when I connect it says commands:7. Then as i try to activate heaters or get the head to move, it just adds to the number of commands. I cant see anything in the error log.


Also I don’t have the LCD display.

If the commands are "waiting’ then the computer isn’t really communicating with the printer.

Is this possibly a new computer you are using? Check your baud rate settings for the COM port to match the settings in your firmware - usually either 500,000 or 250,000 baud.

Go into the printer settings make sure reset on connect is set to disabled.

Thanks for the input- I reinstalled and set the Baud to 25000- Bingo, we are in business!
I will check the other settings .

thanks again,


Darn- all was going well then the print fails. I have an error message “To fix the print problem then resume”. I have tried a reinstall but I still get the same message. Neither of the heaters is working. Manual drive works in X and Y and home but I cant drive the Z axis manually. Any ideas?


What is the Z axis doing?
Also when you set the reference voltage for the steppers did you set them to 0.55?
The manual says 0.425 but 0.55 is the sweet spot.
Do not go over 0.6 as they will over heat and do strange things