UBEC challenge

[TonyS]

I took some good advice lately and invested in a UBEC to cut out the extra weight of an RX battery.

The set-up comprises:

4S 3700 mAh battery

125A Castle Creations ESC which demands a sep UBEC or Rx Battery for any power over 3S

An 8S, 5A UBEC

Spektrum AR6200 Rx

 

I've detached the red wire on the  output lead from the ESC as required. This is connected to the Throttle port of the Rx.

I've soldered the power connections for the UBEC to the battery input cables of the ESC and connected the output to the battery port of the Rx.

What happens is the LED's on the Rx blink rapidly and continuously.

If I disengage the UBEC from the Rx and substitute a sep Rx battery it works!

 I thought that my power connection between the ESC and UBEC might be at fault but if that was the case the Rx LEDs wouldn't blink.

I know that the Rx and ESC work so that leaves the UBEC...

Do you think it's knackered......? 

 

 

[Tim Mackey]

have you checked to see if there is a voltage present at the UBEC output leads - use a multimeter and check - it should show around 5V or so. If it doesnt, then its duff.

[TonyS]

Wish I had a multimeter........

[Tim Mackey]

Tut tut

No self respecting modeller should be without at least one MM.

 

 

Edited By Timbo - Administrator on 15/11/2009 19:26:07

[Tim Mackey]

Hmm, linking seems to be out of order at present... I will let the tech guys know.

 

http://www.maplin.co.uk/module.aspx?moduleno=37279&C=Brilliant1&U=Xmas%2009%20-%20Tools&T=multimeter&gclid=CLPfu5XdjZ4CFUYA4wodJjsMog

 

[TonyS]

Now Timbo,

When did I ever say I had any respect for my modelling..?  

OK. Something else to add to the letter to Santa.... 

[Former Member]

[This posting has been removed]

[TonyS]

Only a tenner !!! You're clearly not from Yorkshire.....

[Peter 'Ivanna Crashalot' Savage]

I got a multimeter for my birthday shows my devotion to electronics!

[TonyS]

OK chaps,

Multimeter acquired and apparently all is well in terms of voltage off the outlet wire of the UBEC. Where do I go next? Any ideas? 

[TonyS]

Actually, and this isn't off-thread as it relates, does anyone know where I can review the AR6200 Rx manual online please? I'm sure that the LED should be solid when bound not blinking rapidly. What does blinking rapidly mean?

Thanks 

[Pete B]

Here!

 

Pete

[Pete B]

The Rx light will only flash if it is either not bound to the Tx on switch-on or encounters a momentary loss of power (brown out) after having bound.

Is the Tx too close to the Rx?  - it may not bind if it is too close.

When you used the separate Rx battery was the Tx moved away? A slight difference in placement might have made all the difference.

Is the UBEC to Rx connector dodgy? Is there a dry joint where you soldered the UBEC lead to the battery input cables.

Have you another Rx you can connect it to?

Have you another UBEC you can try?

All you can do is test and eliminate all the above possibilities, Tony. If it still isn't resolved, then I can't think of anything but an internal fault in the UBEC, unless Timbo can come up with something else.

 

Pete

 

 

[Tim Mackey]

Nope...youve covered everything there Pete

Incidentally, my wifes slope soarer "refused to work" the other day up the Orme and upon checking it over back home, I found the small 3A regulator I used (  to drop the Lipo voltage ) for Rx power was faulty. The same symptoms... off load it showed 5V output, but when plugged into the rx  - the Rx was dead. I replaced the regulator, and all is well again.

[Myron Beaumont]

Timbo

Did she buy you some sticky buns for fixing it ? Or maybe some more foul weather gear for your slope soaring ? Sado- masochism comes to mind . Yesterday I was flying my tiny helicopter in the garden (of 'ers) -No wind at all !

[TonyS]

Thanks chaps.

Will start working my way through the list........

Too close is a possibility - Tx was only 6 to 8 inches away from the RX...

Tomorrow evening's project... 

[Ed Kershaw]

There is one other possibility.  Sometimes rxs don't like what they see from (poorly filtered) switching becs.  This one cost me a model.

 

Ever since then I have used the UBec from Gordon Tarling, which, although a bit pricey, seems steady as a rock.

 

 

[Allan Bowker]

Deja Vu

 

Fortunately my problem was as simple as a dead UBEC

 

Good luck!

 

May the solution be a cheap one.

[TonyS]

Ah, still no joy from my UBEC and a Google search on Gordon Tarling seems to suggest he shut up shop some time ago.....

I got mine from Giant Cod.  

[Tim Mackey]

If you got it from Rob @Giant Cod, and its a duffer, he will gladly excahnge it ...just call him or email - tell him I sent you I get all my UBECs from him these days, just as cheap as using HK with current exchange rates being what they are.

 

[TonyS]

Now this is getting more and more curious....

I read somewhere that the power out connector from the UBEC doesn't plug into the battery socket on the Rx but any other spare socket. Can't for the life of me think why but I thought I'd try it and.....it works. Well, kind of.... 

Now, everything is working  - elevator and aileron servos and throttle - however the Rx blinks slowly and continuously.

 

Couple of observations...

 

Why are UBECs supplied without instructions? if indeed it is correct that the output goes to a spare non-battery socket then it would be useful to be told.

Secondly, why isn't the Rx LED constant?

 

Odd! 

[Tim Mackey]

The positive supply and ground "rails" are all linked across any and every socket on the Rx Tony - so theoretically it should not matter one little bit which socket is used for the supply ( except of course the ESC BEC as this also carries the required throttle signals )

I have many UBECS powering all sorts of models, some plug into the batt socket, some plug into other spare sockets...all work fine.

I cant answer the question about poor / missing instructions - I do agree with you though.

I have forgotten which rx you are using.... I cant speak with authority on any other than the spektrum and hers the answer to that .

There are two different "blinking LED" situations.

1) Rapid blinking - Rx awaiting a proper bind operation

2) Slower blinking - Rx has suffered a brown out. This needs abit more explaning.

A brown out is also created whenever the Rx suffers any loss of power whilst the Tx is transmitting. So for instance, if during normal bench hook ups etc, the power to the Rx is momentarily disconnnected, and the Tx is not switched off before power is reconnected...it will flash. Always ensure that the Tx is ON before connecting the Rx power, and all should be OK. To re-boot correctly after "playing around" on the bench, switch everything off, and then back on in the correct sequence. HTH

[Pete B]

I can't think of any reason other than it is not binding, Tony. Whilst the UBEC can be plugged into any spare socket, commonsense (and natural tidiness!) dictates that if there is a socket for incoming power, ie 'Batt', that is the one that would normally be used.

 

I think the reason few are supplied with instructions is that there's only one way to connect them normally and you don't have much option.

 

Try re-binding the Rx (using a spare socket for the UBEC) and make sure the Tx is a good yard from the RX. What's your binding procedure? It should be- put bind plug in 'Batt/bind' skt, connect power to Rx (any skt). Should get fast flashing light. For Dx6i, hold trainer switch over, switch on Tx. Wait until Rx light locks solid which may take a few seconds. When it does, remove bind plug from Rx, switch off Rx.

 

Switch off Tx. Switch on Tx, switch on Rx, Rx should lock in a few seconds.

 

Sorry if that's a bit basic but then we'll all know where your system is at!

 

Pete

[TonyS]

Thanks Timbo / Pete,

All advice taken and the set up is now working properly -  I must have switched on in the wrong sequence or something even though I am usually pretty disciplined with this having started with the little Blade CX3. If you connected the battery on this before switching on it powered up and went crazy . After chasing it around the house a couple of times I got pretty good at checking the Tx was on first.......

Never mind. All better now....

Next job is to install the electrickery (It's not going to be fun as the wires from the Wild Beast motor are as thick as a wire coathanger but not quite so flexible).

Thanks again.

T 

[Myron Beaumont]

Is the minimum distance thing important when binding ? If so I wonder if some of the probs I've had in the past are to do with being too close &/or indoors ?(reflections - waves). Another thing I would like to know is -If you're not "bound" satisfactorily ie "peace of mind Knowing it's OK " .-If you re-bind, do all the interactions between the Tx & Rx  set themselves up in a completely different configuration?

One for Timbo I reckon