strange power glitch

[cambs flyer]

I installed a new Aileron servo this morning as I'd broken the teeth trying to adjust trims in the wind on Tuesday, blade had a slight off power hit teeth broken, no other damage.

So I installed it, sat her on a stall adjusted the trims so the Swash was level, moved the throttle stick half up and down, went to the field adjusted the trims a little after a few small hovers then perfection, she was hovering and moving as sweat as a cherry.

As she moved a little away from me the motor for a split second lost power, like a burp, so I pushed the DX6 Ariel to the up position, but I still had these split second power glitches.

Until I had her a bit further away and was banking slightly and all power was lost, luckily she landed on a very soft grassy area, I've bust a small plastic arm in the head but no other visible damage, all the servos work fine

But the banana leads that go from the ESC to the motor were out of each other a little with the black lead almost out over half way, I usually have them tapped together but didn't today, could this have cause it? or could they have been nudged when she landed hard, my gut feeling thinks it was the loose leads, as I've had her much further away from me before and shes been fine.

I'm really pee'd off I was doing snake like turns forward, I even Had her hovering side ways to me, fairly close and she was as good as gold, but about twenty feet away the link was lost and luckily she wasn't high and it was on soft grass as I say, but any ideas chaps?

It's a bastard being brought down when it wasn't pilot error, at least if it was I could be kicking myself right now.

Thanks.

[jimheli]

well you said you normally tape the connection but did not on this time so id say that's the problem so as they loosened the small miss in power

[cambs flyer]

Thanks Jim thats my line of thinking, plus the grass was fairly high, so they may well have become loos during take off and landings, the take offs being quite rapid so the grass didn't have chance to snag the landing gear and pull her to one side.

[jimheli]

Thanks Jim thats my line of thinking, plus the grass was fairly high, so they may well have become loos during take off and landings, the take offs being quite rapid so the grass didn't have chance to snag the landing gear and pull her to one side.

well hopefully mate id say so tape them & stay low hover & see what happens ,lol

[moyesboy]

Several things can make the motor shut down.

If the servos pull too much current from the BEC on the ESC then it shuts down, the rx stops so the ESC stops. The servos stop drawing, the BEC recovers and the Rx comes back on and the power comes back. This can happen repeatedly and quite quickly. check for binding linkages and stiff servos that might draw too much current.
A spectrum with quick connect will behave the same, if it doesn't have quickconnect and it does this then it'll be in the deck by the time it recovers.

A battery that is not up to the power draw will cause this. The ESC will shut down due to low voltage and might come back if the lipo recovers.

If you have any power fluctuations such as motors suddenly slowing then land and try to identify why before you carry on or its likely to end in disaster.

I prefer deans connectors rather than two separate connectors.

[cambs flyer]

The battery was charged and each cell had over 4.20V so there was plenty of power.

But until today's five minute flight I hadn't experienced any motor probs' apart from the other evening when she was far away from me and the Dx6's Aeriel wasn't in the "up" position, that solved it there and then.

This did happen the other evening just the once and when I put the RX Aeriel up it solved it, and she was a long way from me at the time.

All I done this morning was replace a HS55 Servo as I'd knacked the last one, before this mornings flight all had been well.

But as I say the motor to the ESC are banana plugs and the black lead was half out if not a tad more when I picked her up and the others were all out a little.

Couldn't this be a case of where the black lead was in by a hope and a prair that the connection was weak and it just bombed out.

As I do usually have the connector's taped together so they don't move, I replaced the landing legs screws last night and I had to remove the tape so I could get to one of the screws, but I never re-tapped it back.

Servo wise it's only powering what it had before even if one is a new 55.

Apart from that this is going to become complicated to solve and I daren't fly her high just in case it happens again.

I'm seeing Pip later so after the broken bit on the head is hopefully sorted, the only thing I can do is walk about 30 feet from her, lift her up 12" and mover her about until it (hopefully Doesn't) happen again

[cambs flyer]

I take it the ESC naturally gets quite warm, as I've just done a simple servo check with the throttle hold on, and it got a little warm just sitting there, while I twiddled with the sticks for five minutes?

[funfreex]

Thanks Jim thats my line of thinking, plus the grass was fairly high, so they may well have become loos during take off and landings, the take offs being quite rapid so the grass didn't have chance to snag the landing gear and pull her to one side.

If the bannana plugs are loose enough to have to tape them together there is a potential problem as it will still be a dodgy connection!

[scallybert]

If the servos pull too much current from the BEC on the ESC then it shuts down, the rx stops so the ESC stops. The servos stop drawing, the BEC recovers and the Rx comes back on and the power comes back. This can happen repeatedly and quite quickly. check for binding linkages and stiff servos that might draw too much current.
A spectrum with quick connect will behave the same, if it doesn't have quickconnect and it does this then it'll be in the deck by the time it recovers.

Another reason that it's a really good idea to have QuickConnect is that the orange light on the Rx flashes slowly after one of these brown-outs. This is a very useful daignostic aid/warning.

ie if the light is flashing after a flight, you need to address a problem.

QC comes with v1.6 of the Spektrum receiver microcode (or from an update), and there's a simple check for if you have it. There's a description here (I can dig it up) of howe to obtain it.

[cambs flyer]

Another reason that it's a really good idea to have QuickConnect is that the orange light on the Rx flashes slowly after one of these brown-outs. This is a very useful daignostic aid/warning.

ie if the light is flashing after a flight, you need to address a problem.

QC comes with v1.6 of the Spektrum receiver microcode (or from an update), and there's a simple check for if you have it. There's a description here (I can dig it up) of howe to obtain it.

Please if you would that would be great.

Cheers mate.

[scallybert]

Apart from that this is going to become complicated to solve and I daren't fly her high just in case it happens again.

I'm afraid this sounds really familiar.

I'm in the middle of an epic saga trying to fix something similar with an EP100.

In my case it seems to have been more than one problem, but it's been quite bizzarre.

One thing that does seem to be the case is that it's got worse with warmer temperatures. I think this means motors have to work harder to keep the heli in the air. This means higher currents, plus worse cooling - both of which make things get hotter - which increases winding resistance - which makes it all worse.

Decent connectors are your friends (I've been advised to solder motor to ESC - which I have). Things which previously appeared 'ok' may now be marginal as the higher running temps make them work harder.

I fixed a similar problem on another EP100 by lowering the gearing (increases motor revs, reduces current, for given head speed & pitch.) This isn't necessarilly your problem, though.

I think you're being smart to fly very cautiously until you've got the problem sorted.

[moyesboy]

battery was charged and each cell had over 4.20V

Lipoi cells should not be charged over 4.2v per cell. That is where my cellpro stops and my other charger with balancer stops a bit lower.

True everything works a bit harder when its hot, but the battery should be delivering better (unless it gets too warm). The motor efficiancy goes down with heat - the magnets get less magnetic and the electrical resistance goes up. However in cold weather you notice the drop in lipo performance much more than any gain in electrical performance.

The motor to ESC connectors shoudl be so tight they are difficult to part or connect with your fingers. Give them a squeeze with pliers.

The Esc will normall yget worm when the motor is running. The BEC part ofit will get warm just running the servos etc. Give them a good execising for 10 minutes and try and apply a bit of load on the servos with your hands to see if you can cause a BEC problem.

The other thing is static, which will be worse with low humidity. Lube the belt with silicone spray/mrsheen/pledge.

What ESC is it?

[cambs flyer]

Align RCE-BL25G

Thank you mate the banana connectors are very loose between the ESC and the motor, so you say pinch them a bit so they bite and are tight.

My charger usually chargers between 4.19 - 4.24V per cell.

My new 12bit charger charges each batt at 4.19-20V spot on everytime

OK so the motors struggle a bit more in the Summer, but do you think this looks like loose connectors from the ESC to motor could be the villain here.

You see flyer's in Florida 3D there Trex's under tropical heat, I'm talking about split second blips and one total power failure, but my line of thought keeps going back the the loose connectors and the fact they were half hanging on to each other..

Thank you for you support as with everyone here, many thanks.

[scallybert]

Please if you would that would be great.

http://www.rcheliaddict.co.uk/showth...=harlow&page=2

Posts #17 & #20 .

NB, the postcode is wrong - see my (probably) correction.

It's easy to check if your Rx came with QC. If it's an AR6200 that came with a DX6i it probably did, otherwise probably not.

[cambs flyer]

Cheers bud'.