Have Just Finished assemble and board doesn't work

K8200 3D Printer K8200 - Wiring and electronics
1

Ok have just finish the assemble, connected the control board, plug in computer, can see it com 12. Now turned on power, all LEDs go out. Uhhh. Could there be a short? I disconnected all motor and heaters. Turn control board on. Again still no LEDs. Check step motor with another project control all seems to work. Any ideas?

2

Hi alpallan,

the LEDs should light up as follows:

  • USB cable connected: LD5 and LD6 (red and green, next to USB socket) constantly on
  • main power (15 V) on: LD5/LD6 go dark, only flashing when data transfer is active; LD1 (green, between ATmega and XSTOP header) flashes twice, indicating reset of ATmega

All other LEDs should light up only when the appropriate part of the board is active. LD1 of course shall also blink when you press the reset button (P1) on top of the board.

Cheers,
kuraasu

PS: most users here are from Europe and N-America, so you’ll mostly get answers “over night” …

3

Yes, you are correct, I have read though the forum and pick up on a few tips. I have two driver motor control units fault. How I came to this, was when I test for voltage on two boards, they had zero voltage. I took these two motor boards out, and then used the manual control panel. the red led to each motor control now blinks. Even with the empty slots. I can also control the extruder head element and the heat bed. When the other two units are in there is no response to any command. However the motor do not move they vibrated ( Even without a load), I have check the voltage and set at .425 volts and have try it at .55 volts this no change. Any Ideas?

4

Hi alpallan,

that’s as it should be.

Could be a wiring problem, a motor that runs only on one coil (disconnected wire or short between two wires) will not turn but only vibrate a bit forth and back. Check the resistance on the motor plug, disconnected from the controller board. Pins 1 & 2 should have around 2 to 2.5 Ω, pins 3 & 4 the same, all other combinations should read as open / not connected.

Cheers,
kuraasu

5

Have check the resistance measuring 1.5 ohms between pins 1 &2 , 3 & 4, no shorts between 1 & 3 & 4. Check all motors all the same. So I can rule out wiring. Whats the next step

6

Hi alpallan,

check the voltage from the power supply at the screw terminal, should be 15 V.

Have a critical look at the board, e.g. whether any component is hot. Check the 5 V line (against GND, both are available and labeled in top right corner, where the pin headers for the LCD can be soldered), is it stable? The input voltage can be a bit higher than 15 V when the board is idle, but the 5 V are regulated and should measure with max 0.1 V deviation.

If everything checks out so far, switch the motors and motor driver boards around and try different combinations. That’s usually a good way to check whether the error is located in the motor, the driver, or the controller board itself.

Cheers,
kuraasu

7

Hi,

[quote]check the voltage from the power supply at the screw terminal, should be 15 V[/quote]15.30 volts
4.96 volts on the 5 volt rail

[quote]Have a critical look at the board, e.g. whether any component is hot.[/quote]7805 is hot to touch Running at 71 Deg C

[quote]If everything checks out so far, switch the motors and motor driver boards around and try different combinations. That’s usually a good way to check whether the error is located in the motor, the driver, or the controller board itself.[/quote]have swap other motors all have the same result x, y, z and extruder.

So where to from here ?

Regards

Allan

8

Hi alpallan,

the voltages seem to be ok, however the 7805 should be “cooler”, usually below 50 °C.

There are two possibilities: either the faulty motor drivers damaged the voltage regulator (or vice versa), which would mean that the board has to be replaced, too. Or the 7805 only runs at a too high load. It does have overload protection and would normally regulate the power throughput to a safe level, but it can of course get hot in such a case.

Using the voltage regulator as an indicator, you can locate the error as follows: recheck its temperature with all motor driver boards (and the USB cable) unplugged from the controller board, that’s the most un-loaded condition for the 7805 that you can generate. If the regulator still gets hot, it indicates an error on the board itself (i.e. in the ATmega, the 7805, or the board circuits). If the temperature remains at a moderate level, plug the motor drivers back in, one at a time, and reconnect the USB cable. Monitor the temperature at each step. You can also re-“test” the two faulty boards like this, maybe they did not work well because of a broken third driver.

Since at least one component (possibly more) will require a replacement: where did you buy the printer? Local distributor, or mail order?

Cheers,
kuraasu

9

Hi Kurassu,

There is no load on the board, only the two motor control board are left in. Motors are unpluged.

Extruder heat and bed are switch off, and unpluged.

I would suggested there has been a cascade effect.

[quote]Since at least one component (possibly more) will require a replacement: where did you buy the printer? Local distributor, or mail order?[/quote]Local distributor, just been appointed, their first problem

So we will see how they will deal with it

Regards

Allan

10

Please use the [quote] tag instead of coloring your answers

11

Thanks for your input new to forums, I will take on board your advise.