Lipo Short Circuit Test (Turnigy Nano Tech)

[cjcj1949]

I've just managed to connect my 3S battery the wrong way round to the esc. Perhaps having connectors that can be reversed isn't a good idea, but they can be disconnected quickly which is what I managed to prove. I have found that escs don't like the volts reversed and will smoke. There seems to be only one component that's melted the plastic but I don't know what it is. Possibly a diode, although I don't see what one diode would be doing on its own except for preventing the esc from blowing up when reverse connected.

Anyway the interesting thing was that the battery didn't blow up and instead the intercell connection melted, proving that Turnigy batteries are fail safe. Is there any way to connect these tabs, they look like aluminium and aluminium soldering seems to need a torch.

[Dedcalm]

Guess the diode is a 'free wheel' diode useful with inductive loads. It would have got very hot as it would drop 0.7 Volts across it as the current flowed with little resistance but it would have protected the FET's I guess.

I've not had any issues soldering to the tabs on Li-Po cells in the past but I have no idea what the tabs are actually made from, always guessed some thin mild steel TBH.

[Zeeflyboy]

Not steel

Usually either aluminium, nickel, or a bimetallic tab with alu on one side, and nickel on the other.

Both can be a pain to solder, good quality solder helps a lot.

[xygax]

We in the consumer powered by own batteries trade call the diode an idiot diode..... came from about 1980 when the 1n4001 made me loads of money from 'prat fee' for adiode and a 4A fuse.... CB Raido.... give a numpty a rig and watch the fuse blow...

Steve

[Ritchieme]

I would like a pound now for every 4001 diode I changed in CB radios in the 80,s, those were the days, eyeball eyeball 10 10 :-)

[cjcj1949]

I was making timers in the 70s and we did a mod to make the 1n4007 (1000v) diodes last a lot longer. Unfortunately the theory wasn't quite right and our customers managed to blow them up. On the esc I didn't expect to see a diode on its own. I'm not sure if the freewheel diodes are separate these days or part of the fets, but I'd expect six of them. I have another good esc that's now in the heli and I did get the number of the diode but I couldn't find it. I think it was a S6??. Might be a 6 amp schottky I suppose. I can buzz out the connections. It's a EnErGy 40 amp esc from JP.

[Delarado]

It never ceases to amaze me how clever people are on this forum.

You with your diodes, zeeflyboy with his fancy antennaes so on so forth. Im 27 and quite a high level techy and I have no idea what your talking about! (At least when it comes to all the numbers your quoting, I just about know what a diode is!)

[cjcj1949]

It's a SS36. A 3 amp 60V Scottky. Don't confuse clever with knowledge. The 1N4001- 1N4007 diodes were used all the time. They are just 1 amp ordinary diodes used as slow rectifiers. The 1 to 7 on the end is the reverse breakdown. The 1N4007 was a 1000V reverse diode. Scottky just means fast and lower volts drop. Silicon diodes are about 0.7V when on and schottky are about 0.2V. Scottky diodes get used in escs. There is a lot of complicated maths and quantum physics in electronics, but you can get a very good idea of what's going on by not knowing anything about the complicated stuff. Just ask a question. This forum is unusual. People answer questions they know about without trying to impress anybody, and more importantly if people don't know they say. If you look at most peoples reputations you'll find a lot that give as much thanks as they get. What's important is what works and what doesn't and what there is a difference of opinion on, like ....