ESC troubles

[Jonathan Lewzey]

Does anyone have any ideas as to why my brand new (10 flights or so) Melody 18/22 amp ESC suddenly started smoking when I connected the flight battery?

To help - details of the power setup: -AXi 2212/26 silver line, HiModel Melody 18/22 ESC, GWS 9x5 prop, Himodel 1300 20C 3s Lipo, Jeti REX 4 rx, 2 servos (SD200 & Esky micro), Airframe: P-40 kittyhawk.

Any thoughts?

I thought possibly - the AXi was not compatible with the cheapy ESC

                             - the motor was pulling too much current (shouldn't be - motor draw 11A, ESC rated at 18A)

                             - component failure

What should I get as a replacement (considering i'm not rich)

-the same again

-Jeti ESC to match Rx and motor

-Synergy ESC (looks OK)

-Hacker ESC

 Jonathan

[Allan Jordan]

 Hi Jonathan, It sound as if your ESC was not up to the job doesn't it? Never buy cheap items that you are going to put in the air... .  it is just false economy and could even be dangerous. I'm sure that John emms at Puffin Models would put you on the right track.

 USUAL DISCLAIMER APPLIES

 Regards Allan J .. 

[Tim Mackey]

well as no-one else has suggested it.....dare I ask - did you get the polarity wrong?

As for replacement, well jeti are the dongs danglies, so keeo the rcvr, and the Axi is also good gear, even the silverline range, so I guess trhe answer is a JETI ESC. ( the best ) 

[Former Member]

[This posting has been removed]

[Jonathan Lewzey]

I am 100% sure it is not reverse polarity as my batteries only fit one way round. I use 2mm corraly connectors with male on the positive (battery) and female on the negative for all my installations.

I was going to try the test with the rx, but was just getting over my initial fury.

Can I just point out that cheap stuff is not always a false economy as I'm approaching 100 flights on my sub - £20 ESC and brushless combo in my shock flyer. But i think i'll buy something a bit higher quality for it in the future.

[Julian Beckett]

Yep I'll agree with Jonathan here. There's a ton of good cheap gear about now.

I've fallen into the designer label trap myself in the past. I guess there may be an argument for it at the cutting edge, but with the cooking middle ground it just ain't necessary to buy the latest 'man jewellery' all the time.

Plenty of club mates are buying cheapie brushless motors, cells, esc's etc off the web and having a lot of success for buttons. If the odd thing does go pop, they haven't lost a kings ransom.

Have a look at United Hobbies website for some idea of the huge savings on your average indoor stuff.

cheers

J 

[Tim Mackey]

I agree, and I use this supplier for a lot of gear

However, there times, as you say, when you know you need to use quality equipment, EG: I would not trust a 1/4 scale model with cheap LiPo batteries for the radio. 

[Jonathan Lewzey]

Although Dad is reluctant that I spend so much money on an ESC, I think i'll try a Jeti unit with the AXi and Jeti Rx as hopefully it'll be more compatible. One thing I forgot to mention was an electronic whine from the model in the motor start-up stage. Could this be similar to the multi engine electric problem in this months RCM&E where the ESC doesn't "understand" the motor and fails to start the motor - because the ESC is inferior it blew?

I think i'll still use the cheaper stuff in future, but only with the cheaper motors on small models. e.g. use cheaper stuff on my Tony Nijhuis Zero, but better quality stuff in a higher performance model such as a Multiplex Funjet - which I plan to buy in the near future. A sensible approach?

Jonathan

[Tim Mackey]

Well that all depends on where you place your values I guess.

A foamie fun jet at 40 odd quid, or a hand built TJ designed "proper aeroplane" Hmmm I think I know which would get the cheapie stuff it they were mine.......

[Jonathan Lewzey]

I suppose so, but I don't really want my zero to be motoring along at 100mph+ do I?! I thought that as the model is more of a danger at the sort of speeds I require, I should install better quality gear.

I also use cheap lipos for all my models. They're the Himodel ones and they're quite good. For instance, a 540mAh 3s 20C shocky pack costs me just £10. I've never had any problems and decide when it is approapriate to start ballancing. Do you think this is a good idea?

[Julian Beckett]

The only problem with buying from China, is that you have to understand the cultural differences. Equally, It's no good expecting 3-5 day turnaround if you've ordered stuff that's clearly marked out of stock! Dealing with customer service departments can be a pain, and ordering at certain times of the year (Jan-Feb), can be a real headache. A bit like trying to get anything done in Italy during August! - they're all on holiday!!!

If you do buy cheap from the Orient and it goes pop, don't throw a tantrum when your emails go unanswered for days on end. Chuck it in the bin and buy something else. After all, you saved a fortune in the first place didn't you! I've found some very cheap and reliable product lines overseas.

Some items are best left well alone. Chargers for instance. I learn't that lesson the hard way, buying a RC-Power 601BC charger at a huge saving from the LHS. However, when the magic smoke came out of it some days later, and it stopped working I quickly realised that return postage etc was going to add up to almost what I'd paid.

If I'd bought it from a UK supplier at least i could have battered their door down!

Cheers

J 

[Julian Beckett]

I don't think you'll have any issues with an Axi motor and Jeti ESC. Almost a match made in heaven!  But pricey...

I was thinking about your ESC problem. Was the ESC configurable in any way. Sometimes they have to be programmed either with a bespoke device or from the transmitter via the throttle stick, to suit the number of poles in the motor, timing, configure braking etc. I'm no electronics guru however. Just a thought... 

cheers

J 

[Tim Mackey]

I doubt that even if the timings and braking settings etc were incorrect that this would release the smoke. Sounds like either reverse polarity ( which now sounds equally unlikely ) or the motor effectively shorted out the load and cooked it. Any half decent ESC should have overload protection anyway. The whining noise is not familiar, ( most escs send short bursts of power to the motor in order to generate a "beeping" noise indicating settings ) but hese are distinctive tones, not a consistent whining. Other motor failures -brushless anyway - are ususally just broken or loose windings, or damaged / loose magnets, and these usually result in noises other than a "whining"

Likewise, bearing failure would be screeching, and noticeable when turning by hand. 

Send it back and await the report. let us know the post mortem results though please.

Julian's summation of the buying abroad experience is very accurate.

[Flash1]

Just buoght a 3S 2300 20c Lipo from Hong Kong £13 +£4 postage. Took 6 days.

Same battery Locally £45.

When I look at the labels they are both MADE IN CHINA.

Who is getting ripped off?

[Tim Mackey]

Just because they are both made in China does not mean they are the same products! 

[Danny Fenton]

Just to throw my twopenneth in here, I have been using the gear from United Hobbies (HobbyCity) and have had no failures, (12 orderes to date) even their lipos have out performed the "branded" ones I have. though I only use those on park flyers. My bigger models on 6 and 12 cells A123 are happy on UH motors and ESC, 3kw motor £20, 110A ESC £30 - easy decision for me. I have also bought a cracking Charger (BC8) from them and have had no trouble. But you are right in what you say you have to swallow a failure as the return postage is so high.

One thing that has not been considered is the legnth of the battery leads, Castle Creations (pretty darn good ESC's) recomend 12" max combined length. Anything longer and the inductance in the wire will send a massive surge down the line and zap the MOSFETS on the ESC. Also watch extending the batt leads with a wattmeter or Eagle tree that can also push the lead length to far. The recomended way for long runs is to use short cell leads and longer motor leads, the high inductance of the motor reduces the effect of the long cables.

PS Timbo, we must stop telling people to use UH, no wonder they never have any stock

Danny

[Jonathan Lewzey]

Whoa - hang on a minute

-I don't tend to buy direct from china (apart from my ESky honeybee RTF for £90). I get most of my stuff from RCM direct. most of their stuff is HiModel so it's made in china. They mostly have good stock levels - I've never had to wait for something thats out of stock.

-What do you mean by sending it back? i've never sent anything back, prefering to buy new with radio stuff. do you want we to send the ESC or motor back? I was thinking of emailing RCM to explain my problem, but i don't think the controller has a warranty and the motor is definitely not recommended (although well within the mathematical ratings.)

-No, I don't get any whining from the motor when I turn it over. It's good as new - although I haven't tested it yet. I've tested the rx and it's fine - although it seems more glitchy than usual (when I first got it it didn't glitch at all: 10 flights - 1 noticable glitch.)

-My leads are quite long - with my replacement I will make sure I shorten them.

Jonathan

[Tim Mackey]

Jonathan. My suggestion to "send it back" was aimed at the ESC which you seem to have cooked through no fault of your own, or other equipment. Despite its price, it should work as stated, and if it does not, then it should be retuurned to the supplier ( the retailer from where you purchased it )

The reciver is not likely to be the cause of your problem, and can be ruled out of the equation.

[Jonathan Lewzey]

Cool -  I'll email RCM and describe the problem. If they want me to send it back I will.

[Jonathan Lewzey]

i don't know if any one will read this as it's currently on page 2, but I spoke to Sanjeel who runs RCM at a recent indoor meet and he seemed of the opinion that AXi motors are useless as "the magnets often fall off" and "they are poor quality." This contradicts all else that has been said above. He also suggested that if I continued to run ESCs with that motor they would all burn out.

Personally, I think this is just sales talk to get me to buy his stuff so I'm still going to go down the Jeti route. however, I think i will still buy mostly cheap stuff like himodel and Torque motors because they seem to work well when paired correctly.

jonathan

[Tim Mackey]

Not sure that everyone will agree with that statement, but just in case it's true, who volunteers to tell John Emms at Puffin that he ...."sells useless, poor quality Axi motors" ?? any takers?? 

Don't all rush at once now

[Jonathan Lewzey]

Yeah, that's what I thought - sales talk. 

[Julian Beckett]

Mmm, Axi motors fall to bits? What a plonker. What did he do? - run a 2208/34 on a 40 amp controller hooked up to a 6s pack with a 16x8 prop?!!!!!!!!

I'm running a range of Axi's from 2204/54 and above. Some are getting on for 4-5 years old now, and look & run like new.

Unlike some of the other cheap garbage that's cluttering up my workshop...

I reckon anyone buying Axi, Hacker, Jeti, or latterly MVVS, won't go far wrong. 

[nasa_steve]

hi guy's

   axi's used to shed magnets when they were overheated years ago but i've not heard of any recently. the hi pitched whine sounds like the motor was stalled either that or the esc could not start it. have you run the motor on another esc to try it?? i have heard of faulty motors so its worth a try. and so far as Hi-Model is concerned every li-po pack i've had from them has gone and puffed read in to that as you will. i've never had any problems with any pack with engerland cells in though

nasa

[Tim Mackey]

Or even Enerland cells eh Steve ?