Mikrokopter Help!!! Hooked Power up Backwards

[scottyj]

Hey Guys I'm hoping one of you gurus can help, I was building an older version Octo and had a bonehead moment and connected the deans connector backwards and plugged it in there was a pop but no smoke, I can still talk with the FC but the BLC's (ver. 1.2) are all dead (no leds lit ) my question is, can I some how repair the BL's or are they paper weights now and have to buy new ones

Thanks
Scott

 

[kloner]

you talking about esc's?

 

[RTRyder]

I would have to look at the schematic for the 1.2 version to be sure but I don't recall them having reverse polarity protection so you may be out of luck. The pop was most likely one of the capacitors, look around for one with blown open top either on the BLs themselves or the flight controller. I've never hooked up the power backwards on any of my MK but I have hooked up a pair of 4S packs in series rather than parallel, the Hexa took off like it had JATO rockets attached and I knew immediately something wasn't right so I brought it right back down. On landing I heard a similar pop with no smoke, the electrolytic cap on the FC had blown. Amazingly nothing got damaged other than that cap.

Unfortunately the PDB is the first thing to see power along with all of the BL boards. The flight controller does have reverse polarity protection so there's a high probability the FC survived without damage and you have a bunch of toasted BL 1.2, roughly a $450 oops!

Ken

 

[Toymaker]

If it's the Electrolytic capacitors on the ESC's They are very susceptible to blowing with reverse polarity they are cheap and easy to swap with a soldering iron. It's where I'd start! Notice the white stripe with the - sign..That's how the power should be attached.
View attachment 17962

 

[scottyj]

you talking about esc's?

Sorry yes i am

 

[scottyj]

I would have to look at the schematic for the 1.2 version to be sure but I don't recall them having reverse polarity protection so you may be out of luck. The pop was most likely one of the capacitors, look around for one with blown open top either on the BLs themselves or the flight controller. I've never hooked up the power backwards on any of my MK but I have hooked up a pair of 4S packs in series rather than parallel, the Hexa took off like it had JATO rockets attached and I knew immediately something wasn't right so I brought it right back down. On landing I heard a similar pop with no smoke, the electrolytic cap on the FC had blown. Amazingly nothing got damaged other than that cap.

Unfortunately the PDB is the first thing to see power along with all of the BL boards. The flight controller does have reverse polarity protection so there's a high probability the FC survived without damage and you have a bunch of toasted BL 1.2, roughly a $450 oops!

Ken

Thats what I thought Ken thanks for the reply
Note to self never trust the imprinted +/- on the deans clone connectors

Scott

 

[scottyj]

If it's the Electrolytic capacitors on the ESC's They are very susceptible to blowing with reverse polarity they are cheap and easy to swap with a soldering iron. It's where I'd start! Notice the white stripe with the - sign..That's how the power should be attached.
View attachment 22131

Thanks I have a local source for those so i'll give it a try

 

[mephisto]

Oh my god. Condolences.

If you had no Current Limitation and directly connected your Lipo, probably a littel bit more is smashed.

- Certainly the Atmel and the C9 are history (replaceable)
- Certainly the exernal Cap too (replaceable)
- Maybe also one or more MOS-Fet's can be down, you could try to switch them manually (replaceable)
- Maybe interlayer connections are smoked (hard to fix)

It also depends on how long it took you until you removed the power.

However, since the BL Controllers are a security relevant part of UAV's i would think twice before relying on them when going airborne.

To tell anything more, you should post some Hi-Res images of you baked bl controllers..

Also have a look at this thread in the german forums:

http://forum.mikrokopter.de/topic-25939.html