Spektrum Rx & Static Discharge

[scallybert]

[Back from mni-holiday...]

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

I think there may be a number of different ways that static effects can occur.

The way I've been thinking about this, you have 2 (or more) metals parts of the heli, that are insulated from each other. For some reason, these two parts get a static charge between them (eg tail belt behaving like a Van der Graaf generator.) This static charge builds up until the voltage is high enough that it can discharge. I guess this discharge can cause interference, or it can maybe discharge through the electrics, disrupting them.

If you connect these various bits of the heli together, the static charge leaks away before it can build up enough to discharge - so no problem.

I think that's quite a big 'if', though. It's probably not feasible to connect all the metal bits together. So you have to do your best with the likely candidates.

There's also the question of whether to connect them all to the power -ve (or such). I can see why this might help. But it might also result in a static discharge routing through some delicate micro-electronics that might not appreciate it.

[xygax]

Now this is where ohms law has to take over.... If all the metal bits are connected togther ..... Frames Boom Bearing blocks, motor mount and battery -ve the whole system is by definition equipotential bonded adn therefore the build up of static is not posible. Assuming that there is a few Ohms in the frame the only time that static would be a problem is the chage that can build up on the heli with respect to the ground (field) this means taht the only time the heli is vunerable is at the instant of landing when the charge built up on the heli overall can dicharge to earth.
The only place i think is still vunerable is the voltage that could potentially build up between the head and the body due to grease is an insulator.... and hence the head is dificult to bond to the frame...

Steve

[funfreex]

unless it builds up so much static that within 5 feet of the ground the air gap between ground and heli ionises and you get one massive bolt of helilightning!!

Jamie

[brin]

read this it is very informative
http://www.runryder.com/helicopter/t...top=1203227315

[scallybert]

If all the metal bits are connected togther ..... Frames Boom Bearing blocks, motor mount and battery -ve the whole system is by definition equipotential bonded adn therefore the build up of static is not posible.

I'd agree - but that first 'if' is a big 'if'.

eg, you might have threadlock, paint, etc, etc between various of the conducting components.

I've also heard that silicon grease is a good insulator - so using this might mean there's no conduction through (some) bearings.

[scallybert]

Thanks - seems to work

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

Thanks for being persistent about this.

I've put (perhaps rather too much...) graphite lubricant 5101 on both sides of the belt, and motor pinion on the EP100 SE Pro.

I've just run 5 LiPos through it. One on the bench (typically enough to provoke a lock-out); three low-level hovering; and one more regular hovering.

No sign of a problem. No flashing Rx LEDs, etc

The last time it behaved this well was when I used aerosol contact cleaner on the battery connector. I suspect some stray spray ended up acting as anti-static. Whereas I thought it suggested a connector problem.

This seems like real progress, and suggests the problem has indeed been static.

[brin]

well done mate it might not have seemed the way to go but logic tells you that if you stop the static from building up then you are less likely to have an issue thats why i went this way and it was easier than grounding everything to the negitave i'm glad it was of help its nice to put a bit back into the forum

[scallybert]

I ran another 5 LiPos through it without problem, so I'm pretty pleased with that.

Bit bothered about the mess the graphite paste makes, and whether it will fling off, and stop working.

I guess I'll find out, but if nothing else, it seems to have put the finger on static being the problem.