View Full Version : Not Working Keling X3 CNC kit (KL-6852)

03-21-2010, 11:45 PM
Hi Guys,

I have this week-end transformed my manual X3 Harbor fright Mill into a CNC Fusion/Keling CNC Kit for X3 where you can find the info here:


Basically I was expecting a lot hassle on the mechanical part which aside of very demoniac bearings that I had to remove with a puller (the upper bearing of the Z axis), the mechanical portion has been quite easy and I have to thank CNC fusion for that because their Kit is really really awesome.

Anyway, now, I got to the electronic section of it, it would come to no suprise that it was not working, because there is always some that doesn't work. But since I am a hardware design engineer it would come to a bigger surprise that I am writting for help today. You see after doing everything I thought would be possibility the problem I just gave up. So Here is the list of material I am working with:

1 Power Supply PCS48V/7.3A set 48V
3 KL-6852
1 C10
2 KL23H286-20-8B
1 KL34H295-43-8A

The problem is:
That on the KL-6852 there is Green LED to indicate that the power is on and I guess that the board is ok, there is also a RED LED that indicates that there is an ALARM and this where the problem is. Because it is most of time always on Alarm and being on it, it disable the stepper driving section.

So, if I plug the stepper, when I power it up, it automaticaly change from green to red.
if I just plug the 48V and no motor, it will start green but if I try to run MACH3 in one direction it will be fine (always without stepper) and when I change direction it becomes RED again.
So, I did not find any combination that would let me put the stepper on it and be able to control it... so basically I never saw any stepper move so far.

As far as the C10 is concerned, everything is in order, I even checked the cable, it is not inverted or f* up. Pins are 1 to 1, 2 to 2, etc... (it is male/male db25)

I checked with the multimeter, to see if the signal was changing on the output of C10 (pin 2 and 3), I certainly saw a signal going one pin (the PUL) and I think the one changed to for direction....

So, I basically read every possible piece of documentation, read every possible thread to find any answer on why the damn RED led is turning for no apparent reason... So Keling peeps, I quick answer on this one would be appreciated.

Also, the 3 drivers are doing exactly the same thing, did I get duds ? or very finicky pieces of equipment...

Thanks for any possible path of solution...

03-25-2010, 08:25 PM
Hi Guys,

I will respond to my own post since I found the reason of my problems...

I thought that some of you might be interrested by the answer.

I guess being an electronic hardware design engineer doesn't always help since we have the tendencies to overlook stuff and go fast by thinking that we know so much... That was the case here...

What probably happened is I have connected everything the way I thought that should have been, but I did not pay attention to the dipswitches for the current limits and when I moved and install everything on the machine I might connected my wires wrong on the driver, so when it happens (because it did) there was one very hot motor. At that point it was probably too late already, either the motor was smoked or the driver. it just happen that nothing was really working because I was using a shorted motor with different drivers which I happen to smoke everytime that I use the shorted motor on them.
So at the end of the day I had 3 smoked drivers and 2 shorted motors (Nema23). My Nema34 was ok, since I did not use it to do testing. Since the 3 drivers were behaving the same way it was easy to realise that something wrong.

So I decided to investigate further after contemplating the possibilities of buying new ones and after dealing with the Keling guys and the attitude of Geckodrives' sale person, I thought it would be a great idea. So I opened my first driver to realize that one of the MOSFET power transistor was fried (shorted) and actually had 2 transistors (there is 8). The 2 other one had 1 toasted transistor only which obviously was sufficient to make the whole drivers unusable...

So I have ordered those transistor at digikey and I have replaced them and I finally made my NEMA34 worked and all is well now. Tomorrow I will recieve my 2 new NEMA23, so I will be able to reinstall everything and be able crunch on some alu this week-end !!!

For those are wondering what the shorted NEMA23 is, the Coil A and B when measured in ohms show individually 1.4 Ohms, but If you take one wire of one and another wire of the second it should be connected and mines are. So for the 286H, If I measure between the blue and red wire... I have a short... those are the wires of 2 different windings...

Anyway, I thought it would be helpfull for others...



03-25-2010, 08:37 PM
I forgot to talk about the overall experience with Keling...

The overall pricing and shipping and ordering has been more then satisfactory and I have nothing to say negative about it. It was prompt and done properly.

The day I wrote the post, I left a message to them and the next morning I got a call. A that point, I thought it was very good. Naturally the person on the line tried to understand what I did, so he could figured what could have been wrong and I tried to be as helpfull as possible, however, there was some time where it was frustrating since he was chinese with a good accent talking to a french canadian, I think the communication quality was not very good. Finally, he wanted me to take picture of the wiring so he could see for himself if the wiring was good, which I thought was a bit weak since according to him, he never saw any of these problem before... The thing is, I was responsible of what happened so I did not plan on asking him to send me new stuff for free...

So, anyway, the reason I am writting these lines is just that instead of sending him picture I sent him a good email with all my findings about the motors and from that point, the support ended. I never got any answer to it and the worst is the next day I call in to see how much it would cost to buy 2 new NEMA23 with 2nd day shipping and he did not remembered me at all.... I am usually not the type of person you forget unless you really don't want to. So decided to go buy my stuff somewhere else.

In conclusion, if you are dealling with certain problems that are out of the ordinary or your are requesting something that is not part of their routine (confort zone) it might be more difficult to get service.