BL-Ctrl Missing Error and Bad Soldering of Molex adaptor

[ovdt]

One small guide for newbies like me.

After building my Quadro XL kit without problems, I started building Hexa setup with Droidworx AD6-HL frame. I soldered 6 of BL-Ctrl 2.0 to power distribution board and checked all the connections with multimeter if there's a short circuit or not.

I soldered the motor wires, put the FC on the frame and I was ready to test with Kopter Tool.

But, oopss, I'm welcomed with "BL-CTRL Missing" error. I checked C-D lines. There were no problem.

I did a smoke up test with 9V battery. I connected 9V battery to power distribution board and connect the FC via molex to board.

The FC was powered successfully, since I could see the lights on it. Everything seems OK in terms of power. But, red and green lights were flashing together on Bl-Ctrls. Red light means, there's a problem. And Kopter Tool was reporting that no BL-Ctrl is connected. It was obvious that, there's communication problem between FC and Bl-Ctrls.

To check it out more closely, I inspected power distribution board closely. The molex was the last thing I checked and a bad solder was the main problem here.

View attachment 463

The third leg wasn't well soldered to its pad. (You see the corrected one in the pic). That was causing the problem.

I use a setup as in the picture to inspect the BL-Ctrls:

View attachment 464

If you soldered the Molex by yourself, be sure to check out the connections since the legs are so tiny. If you powered up your FC and BlCtrls successfully but Kopter Tool says "No BL-Ctrl", molex should be one the first components to check.

Hope this post helps someone in the future.

 

[Droider]

Thanks for posting that.. I have had my fair few problems with the BL's, BTW they also dont like salt water!;-(( Are you going to lacquer the board when you have finished it?

Also what is the black box connected to the FC by the ribbon cable?
\
Dave

 

[ovdt]

The black box is the part of Xbee wireless set. It makes easier to use kopter tool.

I'm going to spray silicone conformal coating after everything works fine.

I used hot silicone for caps, to glue them to the board.

I'll also add heatsinks to mosfets, since the weather here in Turkey hell hot in summer time (30-40 Celcius degrees most of the time). And ofcourse %60-70 humidity.

 

[connexxion]

I always drag solder those little pins of the molex connector:

http://www.youtube.com/watch?v=t06malVew40

 

[Droider]

Guess that was flux he was applying at the start.. which flux / solder is everyone using.. ?

 

[RTRyder]

Guess that was flux he was applying at the start.. which flux / solder is everyone using.. ?

I use rosin core solder, no messy flux to apply then clean off after the fact. For the majority of the soldering I do I use 22 gauge (.032 diameter) 60/40 with 2.2% flux core and a larger gauge of the same for big stuff like battery wires. The 60/40 refers to the ratio of tin to lead and may not be available where there are restrictions on lead use.

Ken

 

[Aziz]

This was exactly the problem I had when i fired up my MK for the first time. Wish I would have found this thread before today would have saved me some hours of anger