Mikrokopter If This Was Your Problem

[Droider]

After successfully rebuilding my ADX3 I still have two issues. She fleis fine BUT I am not really happy as I have the following issues.

1. I have a missing temperature reading on one BL

2. Sometimes one motor.. the top rear does not spin up at motor start and I get a ERROR 3 on the jeti box. If I power everything down and start up again it will be OK.

I am thinking of identifying the BL that has no temp reading and replacing it, identifying the BL that intermittently does not start the motor and replacing it and replacing the whole BL distribution plate.

comments or suggestions appreciated

Dave

 

[Bartman]

Dave,
Many four or six cylinder aircraft engines only have one temperature probe on one cylinder for the cockpit indication so I probably wouldn't sweat having one BL blank if the others are all working. As for the one BL that isn't starting the motor, what is Error 3? Have you tried to reflash the firmware for it?
Glad you're back flying.
Bart

 

[Droider]

Sorry.. reflash firmware? is this to the BL or the FC?

Dave

 

[Bartman]

the BL. the five unused pads on each BL are for connecting them to a computer so the firmware can be installed. you can probably make a connector with pins and a clothespin or something so you don't have to solder the connector on. If it's acting blinky I'd probably try to make sure the software isn't funky.
disclaimer: i understand less about software than i do women so i may be wrong (If my past judgements about women are any indication then I'm definitely wrong!)
Bart

 

[Droider]

Thanks bart I look it to that.. tonight.. back to work now..

DAve

 

[Crash]

The temp is communicated over the same two lines that adjust motor speed. Who knows what the BL-Ctrl or FC code will do if the temp gets faulty values or no value. I do know that the FC is capable of lowering power at higher temps.

The temp circuit on the BL-Ctrl is pretty simple. I would inspect it very closely. Pic below. Then I would inspect every board for blobs and debris. Then I would reflow the CD lines and the pads on the faulty motor. Then I would inspect the boards again even more closely.

Oh, also clean off any flux goo.

 

[Crash]

the BL. the five unused pads on each BL are for connecting them to a computer so the firmware can be installed. you can probably make a connector with pins and a clothespin or something so you don't have to solder the connector on. If it's acting blinky I'd probably try to make sure the software isn't funky.
disclaimer: i understand less about software than i do women so i may be wrong (If my past judgements about women are any indication then I'm definitely wrong!)
Bart

I don't have the newer boards. Did they make the RX/TX lines easier to access?

 

[Bartman]

http://gallery.mikrokopter.de/main.php/v/tech/Oktoverteiler-oben.jpg.html

aren't the five pads at the corner of each BL for flashing the firmware onto them? is that what you mean by Rx/Tx lines?

 

[Crash]

..deleted..I think I clicked edit rather than reply.

 

[Crash]

http://gallery.mikrokopter.de/main.php/v/tech/Oktoverteiler-oben.jpg.html

aren't the five pads at the corner of each BL for flashing the firmware onto them? is that what you mean by Rx/Tx lines?

Ah, They are similar to the 1.2 boards. Those are pads for a standard 2x5 connector. The other 5 pins are on the bottom of the board of course.

To reload firmware with MKTool you only need to use 2 of those 10 pins. Transmit(TX) and receive (RX). The problem is that one of them is on the bottom of the board and may be difficult to get to.

The other lines are there for an AVR programmer. They are useless to us on the V2 boards because the bootloader is not available.


Either way, I tend to think that it's a physical problem and not a firmware problem.

 

[Droider]

The temp is communicated over the same two lines that adjust motor speed. Who knows what the BL-Ctrl or FC code will do if the temp gets faulty values or no value.

I have seen in the MKtools set up a way of getting to the BL. ALT and settings throws up a BL control panel but is was greyed out.. I think there is a temp max limit in there but cant remember. Not sure what it would be for though.

I will go over it all again tonight and double check the soldering. Thanks for the input Crash

Dave

 

[Droider]

Ok I still have intermittent fault on same BL and motor. even though the MKtool reports no error the motor on it does not spin up its just stuttering.. If I remove the power for a couple of mis it may or may not start up or I get a BL error.. GRRRR.. thinking BL and motor.. any thoughts?

I have re soldered the motor BL connections and checked as closley as my old eyes can see through glasses and a magnifying glass and I cannot see anything untoward.

 

[Droider]

Ok I started giving stuff a bit of a wiggle..found I got a beeping and allmotor stop whe I pushed down on the cap thingymabob. Looks like I could have a dry joint on there.. I strip it down tomorrow and check the solder joint on the cap to the dis board and the bL.

Also I found that the temp sensor on another BL that is just reading zero at start up is not reading accurately. When I did a motor test via MK tools and got the motor running for a while I got a temperature reading but way lower than it should have been so I am guessing the temp sensor is way out of calibration which I doubt there is anything I can do about..

 

[Crash]

Ok I still have intermittent fault on same BL and motor. even though the MKtool reports no error the motor on it does not spin up its just stuttering.. If I remove the power for a couple of mis it may or may not start up or I get a BL error.. GRRRR.. thinking BL and motor.. any thoughts?

I have re soldered the motor BL connections and checked as closley as my old eyes can see through glasses and a magnifying glass and I cannot see anything untoward.

Stuttering is bad and could be costly.

One of the three motor windings is not being energized or switched. It could be the motor or a bad BL or both. One can kill the other.

Desolder the motor wires and check the resistance between each of the 3 motor wires with a meter.

I have seen decent looking motor wire joints that did not flow enough current to properly start a motor. Do you have a pic of your soldered BL-Ctrl?

BTW, A magnifying glass won't always do it. I recently saw a speed controller with a resistor that was floating about .001" over the pad. I think it was sheer luck that I saw it with a microscope. The motor it was connected to was stuttering and burned up a winding.

 

[Crash]

Ok I started giving stuff a bit of a wiggle..found I got a beeping and allmotor stop whe I pushed down on the cap thingymabob. Looks like I could have a dry joint on there.. I strip it down tomorrow and check the solder joint on the cap to the dis board and the bL.

Also I found that the temp sensor on another BL that is just reading zero at start up is not reading accurately. When I did a motor test via MK tools and got the motor running for a while I got a temperature reading but way lower than it should have been so I am guessing the temp sensor is way out of calibration which I doubt there is anything I can do about..

You can try reflowing the solder on the 4 or 5 chips in the temp circuit.

The cap needs to be soldered properly. It takes a lot of heat and the solder MUST flow through the hole and leave a fillet on both sides. Use flux. The negative side is especially important because if there is a weak connection there you can fry every BL-Ctrl board in a not so nice little ring of fire.

They should NOT look like the picture below.

When you get everything going, glue the caps down so that they can't move or vibrate.

 

[Droider]

Thanks Crash.. I intend to take out the dis board and double check everything again.. I check out the wires. I did flow some more solder round the cap which seems to have solver the problem but I could only get at it from having the MR upside down so not really happy. Will remove power dis ring tonight and reflow to make sure the thing is sound.. Ill also test the windings .. thanks really appreciated feed back

DAve

 

[Jake Bullit]

At least you`re not missing out on any decent flying weather at the moment.

 

[Droider]

At least you`re not missing out on any decent flying weather at the moment.

Yeh Tell me about it... what was that rain about today!!

Crash.. seems like the cap is duff.. have dessassembled the trouble som BL and re done it but to know avail. I think the cap is faulty so will ry replacing it tomorrow.. do you normally tin the cap legs before you assemble it or what?

DAve

 

[Crash]

Yeh Tell me about it... what was that rain about today!!

Crash.. seems like the cap is duff.. have dessassembled the trouble som BL and re done it but to know avail. I think the cap is faulty so will ry replacing it tomorrow.. do you normally tin the cap legs before you assemble it or what?

DAve

No but I dip the legs in paste flux and make a big mess that I have to clean up later with alcohol.

I found a pic of the resistor I was referring to earlier.

 

[Droider]

Thanks Crash.. I have carefully removed the BL and made sure everything was good. Carefully re-fitted it with new cap. Now I am getting two blinking red led's and from the MK wiki it looks like this mean phase B is.. knackard.. Is this the correct assumption and does this mean the BL is stuffed?

DAve