Spektrum Rx & Static Discharge

[LaurenceGough]

Don't you just hate it when you spend a lot of time doing something and you really think it's got to work only to find out it doesn't work.....

Next idea is to ground the tailboom bearing, not quite sure how I'm going to do that yet.

I really thought just grounding the tailboom it's self would be enough...

Lights didn't flash today, well at least at the end of the flight. I spun it up on the ground to full speed and the lights didn't flash at all. Although thinking back now I suppose the heli was grounded? (Plastic skids and rear fin?)

[scallybert]

Don't you just hate it when you spend a lot of time doing something and you really think it's got to work only to find out it doesn't work.....

This has been the story of my EP100 SE Pro. Well that and self-delusion...

Next idea is to ground the tailboom bearing, not quite sure how I'm going to do that yet.

I really thought just grounding the tailboom it's self would be enough...

I'm fairly convinced it's static. I've explored power issuse to death, and the LED behaviour isn't consistent with a power issue. (It's different to QuickConnect indication - which I have seen.)

What I'm not so clear on is what to connect to what to safely discharge the static. (Graphite paste, etc, is a popular suggestion, but I don't like the idea of it getting in places in shouldn't, and frequent re-application seems necessary to prevent the problem coming back.)

I'm thinking tail boom, motor base and main shaft. Possibly Rx/ESC ground, but I'm not sure on that.

I'm not sure I understood the copper tape solution (was that Leebert ?), but I guess if you have a non-insulated conductor close to various parts, that will hopefully be an easier discharge path than via Rx.

One thing I've noticed is that many metal parts don't actually conduct to each other. (eg there's an alloy bearing assembly the main shaft runs in, but zero conductivity.) I suspect this is because many metal components have thread-lock separating them. I also believe silicon grease is an insulator.This will make getting a connection to the main shaft interesting...

It would be nice if Horizon/Specktrum had some helpful information.

[Pipistrelli]

I keep reading about static issues on the Rex 500 and now the 450. Thing is, I've owned about 4 different Rex 450's from the 450X all the way up to the SEV2 and I have never had a static issue, The heli and all electronics fly without failure, never had an ESC or Motor failure and never had Spektrum reset.

If static was an issue, would Align not give some kind of guidance of how to resolve it in the heli manuals? Have you considered that something else may be faulty causing this problem and you could be mislead chasing this fault?

[scallybert]

[...] If static was an issue, would Align not give some kind of guidance of how to resolve it in the heli manuals? Have you considered that something else may be faulty causing this problem and you could be mislead chasing this fault?

Mine's a GAUI, and it's interesting that I seem to be the only GAUI person here with problems like this. I haven't ruled out the possibility that I'm an idiot.., but my guess is that the other GAUI people aren't using Spektrum. I'm also exclusively indoors.

Possibly it's where a number of different factors come together.

In my case, I've swapped every single electrical component (at least once), put in different (and bigger) ESCs, reduced gearing, stuck a power meter on it, DVM across Rx power, Spektrum Power Protector, 4 different Rxs. There's not been much of a pattern to it, either - though possibly moving wiring makes it better or worse.

I have no better guess than static.

[LaurenceGough]

I've not had a problem before the last couple of weeks, during which time nothing has changed other than the weather, so I'm guessing static...


The strange thing is on mine only the motor seems to cut for the slightest of a second and nothing else other than a quick flick of the tail, which is most likely related.

Once and a while (very random) the remote RX light flickers every now and then, not a steady flash.



The belt is running in mine without any ground, two plastic pulleys. (think that's the cause?)

Also my main shaft is isolated from the frame.

[brin]

as i have said before use grafit grease on the plastic gears this will totally eliminate the static from this area i ran a tester on the boom ,tail drive ,belt and gears the only static left came from the tail rotors and it has remained this way for several weeks

[scallybert]

as i have said before use grafit grease on the plastic gears this will totally eliminate the static from this area[...]

Maybe I'm being too fussy, and I should be more receptive to this suggestion...

This is just the gear on the mainshaft ?

Does the grease need to be re-applied / how often ?

Do you have a reference/link for the grease you've used ?

[scallybert]

I tried a rough earthing strap - a croc clip on the tail to a croc clip on the alloy main shaft bearing housing.

Sticking a DVM between tail and housing saw ~60 ohms; between tail and mainshaft ~150 ohms (at odds with what I previously saw - no connection to shaft).

Rx still tripped out. Motor shut down, Rx LED flashed as QuickConnect, remote Rx LED solid.

The next step down this path would be to connect the same lead to motor mounting screw. A further step would be to also connect -ve on ESC or Rx - though I'm a little wary of this.

[brin]

if you're anyway near new southgate pop in and i'll give you some if not i'll find out where my mate ordered it from .now something strange we found out the upgraded gears ie the blue ones dont have the same problem mabe its the compound they are made from .we checked two of 450 v2s at the club and there was no static coming from there gears hope this helps
brian

[scallybert]

if you're anyway near new southgate pop in and i'll give you some if not i'll find out where my mate ordered it from .

Thanks for that offer. I think I've tracked some down and it's heading my way. We'll see...

now something strange we found out the upgraded gears ie the blue ones dont have the same problem mabe its the compound they are made from .

It does make you wonder.

we checked two of 450 v2s at the club and there was no static coming from there gears

How are you checking for static ?

One other thing (which is a bit off-topic), if you're based in Southgate, what club do you go to ? What's it like, etc ?

[Aidi]

I have explored this static issue on the 500 to death. Personally, i have grounded th -ve on the ESC to the motor mount bolt on the frame, and the bared some metal on the tail boom and grounded that to the frame too. I also squirt a small amount of Mr Sheen down the tail housing onto the belt, and squirt onto the main gears.

Since doing that, i have yet to experience a hit. Prior to the mods, i was getting kicks on the tail. Sometimes only 10-15 degrees, but sometimes about 40-50 degress. Both were pretty nasty to experience.

One post i did read (but cant now find) is the next thing i will do. It appears that the belt can rub very slightly against the box housing which connects the heli itself. The guy who found this to be a problem was having major problems and after a bit of "dremel" work to the inside of the tail mounting block pretty much eliminated the problem.

I think its one of the those subjects with so many factors causing the same effect. I just went with what was the most popular! Fingers crossed mine will now fly without a glitch which will cause it to crash (famous last words)

Rgds
Aidi

[LaurenceGough]

Perhaps that's where I'm going wrong. I didn't really want to mess around soldering again but do I really have to connect the frame to the battery negative, isn't the motor connected to the ESC/lipo?

[brin]

Thanks for that offer. I think I've tracked some down and it's heading my way. We'll see...



It does make you wonder.



How are you checking for static ?

One other thing (which is a bit off-topic), if you're based in Southgate, what club do you go to ? What's it like, etc ?

i use a hand held voltfinder which i got from maplins
i belong to the north london flyers club based in botnay bay between enfield and the m25 ,they are very friendly and offer lots of help they fly lots of planks and quite a few helis ,there's a good selection from 90s right down to 400s and also scale

[brin]

i know this might be getting into this a bit deep but can anyone explain to me if all the bits that cause static are grounded where is the static discharged to

[LaurenceGough]

I know where I've been going wrong, at least I think I do.

You're meant to attach the main frame to the lipos negative wire.

Am I correct?