bugger - magic smoke!

[penguineer]

Finally got my order of plugs/connectors and a bit of dumb RGB from Ray today......

Plugs will give me a bit of work to do over the next couple of weeks, but I've had less fun with the dumb RGB nodes.....

The nodes came with one of those simple RF controllers, so I had a bit of a fiddle. See, one of my ideas was to have some form of lighting I could take places on the motorbike and set up around the campsite at rallys etc.

12V is pretty cool - I have a spare bike battery that I can charge up and take with me, the dinky controller gives me basic control over the lights(simple preset colour sequences/flashing or pick my own colour) and she's apples....

Somewhere along the way I managed to reverse the ploarity on the battery connections and release some magic smoke.

The RGB is fine - the controller sacrificed itself. More specifically, it appears that three little surface mount modules blew themselves apart - electronics ain't supposed to rattle.......

Is it possible to replace these, or is there likely to be enough damage to warrant getting a new controller?

The SMDs were labelled SS24 and appear to be these: http://au.element14.com/jsp/search/productdetail.jsp?sku=1017872

Annoyed with myself, but getting used to it....

Cheers

 

[David_AVD]

Got a clear close-up photo of the board?

 

[penguineer]

Got a clear close-up photo of the board?

The outside of the controller - just so's it's recognisable:

PCB:

PCB with destroyed components marked - not left hand one isn't blown to pieces like the others, but does have indications of heat:

I think I may have some issues with the barrel connector for the 12V power pack as well, but I think that's fairly easy to overcome.....

(hmmm - looks like image display is cutting the RHS of the photos off - if you "view image" it's all there.....)

Cheers!

 

[David_AVD]

You'll probably find that the controller will work without those diodes, at least for a quick test.

They seem like back-EMF protection from their positions, but it's hard to tell without seeing it in person. You don't usually see diodes like that on a light controller.

You could always give it a go and see before getting replacement diodes.

 

[penguineer]

You'll probably find that the controller will work without those diodes, at least for a quick test.

They seem like back-EMF protection from their positions, but it's hard to tell without seeing it in person. You don't usually see diodes like that on a light controller.

You could always give it a go and see before getting replacement diodes.

So just unsolder them, clean it up and give it a go?

Cheers!

 

[David_AVD]

I would give it a go!

 

[damo1271]

If you need back EMF protection (Ie switching inductive load) you can either replace the diodes on the board (soldering surface mount parts = ), or connect some 1n4004 through hole diodes (correct way around) 'across' the load where it joins to the boards. For simple back emf protection the differences in specs between the 1N4004 and the SS24 shouldnt matter.

 

[penguineer]

Thanks for the suggestions guys!!!

Picked up some 1N4004 diodes today and a few other bits to try getting this thing going again. Haven't had a chance to get on the soldering iron today - hopefully tomorrow.

I've also got a spare fuse holder I can wire in if I decide to try to use the battery again - something like 5A should be plenty for testing and hopefully blow before the controller does.

Just wondering about how I managed to get things so backwards though......is there right and wrog end on the dump node light strings perhaps? Surely there's no real difference between a battery positive terminal and positive connection on a plugpack? Or did I just get it back to front without noticing(most likely)?

Cheers!

 

[penguineer]

OK - I've had a bit of a fiddle with the soldering iron, desolder braid and the replacement diodes.

No joy. After desoldering it appears that a track/pad that the left diode attaches to was completely obliterated and the damage seems to disappear under the triac - I was able to get a new diode in place attached to an unaffected piece of track that connects to the same place, but no better result.

While power seems to be getting to a point it doesn't seem to be getting out of the triacs(?).

So the problem could be triacs or the logic telling the triacs what to do.

Given that it's all fiddly surface-mount stuff, my diagnosis skills are reaching their limits, and it's a unit that sells for US$10 that isn't critical to this years show I'm happy to call it quits.

Learning experience.

Cheers!

 

[David_AVD]

Bring it along to the next mini with a tag "don't do this!"