Lockout/Brownout Problems - Static is a #1 issue

[alwallash]

Kevin,
I have been following this thread with great interest.
I work in the field of ESD and am impressed with your work.

I have the ESD measuring equipment, but have not purchased a Trex 500 yet.
I have a rule that I wait at least 6 months before buying a new heli, to wait for the bugs to be worked out...! But I can see I am missing all of the fun too.
Besides, I am too busy flying my Trex 600E.

I have attached pictures of these instruments.
The best measurement tool for electostatic voltage is a non contact voltmeter, like a Trek 520.
To detect the presence of sparks, you can make your own dipole antenna and connect it to the scope inputs, or use a Credence Technologies EM Aware.

I took some measurements with these instruments on my Trex600E when it was new. I found that the belt, gears, and main gear charged easily and induced >2000V on various parts of the heli. I recall measuring even up to 8kV! When I lubed the belt, the voltage dropped almost to zero. This is because lube will reduce friction and add conductivity to the insulating plastic parts. Connecting ALL conductors together to keep them at the same potential is also a great idea.

This large STATIC voltage did not affect the gyro or other electronics. The problem is when there is a spark between two conductors at different voltage. Sparks contain frequencies > 10 GHz, so 2.4 GHz rcvrs are not immune to interference from sparks. (They are immune to the <100 MHz noise from ESCs, though.)

If there was someone in the San Jose area with a Trex500, we could pair up and take some measurements with these instruments.

I teach turorials on ESD measurements, some of which are at www.wallash.com. I could also send a pdf file that discusses the measurement of charge, voltage and electromagnetic fields if you send an email to al@wallash.com.

Again, great job.
Al

[fireup]

Originally Posted by alwallash

Kevin,
I have been following this thread with great interest.
I work in the field of ESD and am impressed with your work.

I have the ESD measuring equipment, but have not purchased a Trex 500 yet.
I have a rule that I wait at least 6 months before buying a new heli, to wait for the bugs to be worked out...! But I can see I am missing all of the fun too.
Besides, I am too busy flying my Trex 600E.

I have attached pictures of these instruments.
The best measurement tool for electostatic voltage is a non contact voltmeter, like a Trek 520.
To detect the presence of sparks, you can make your own dipole antenna and connect it to the scope inputs, or use a Credence Technologies EM Aware.

I took some measurements with these instruments on my Trex600E when it was new. I found that the belt, gears, and main gear charged easily and induced >2000V on various parts of the heli. I recall measuring even up to 8kV! When I lubed the belt, the voltage dropped almost to zero. This is because lube will reduce friction and add conductivity to the insulating plastic parts. Connecting ALL conductors together to keep them at the same potential is also a great idea.

This large STATIC voltage did not affect the gyro or other electronics. The problem is when there is a spark between two conductors at different voltage. Sparks contain frequencies > 10 GHz, so 2.4 GHz rcvrs are not immune to interference from sparks. (They are immune to the <100 MHz noise from ESCs, though.)

If there was someone in the San Jose area with a Trex500, we could pair up and take some measurements with these instruments.

I teach turorials on ESD measurements, some of which are at www.wallash.com. I could also send a pdf file that discusses the measurement of charge, voltage and electromagnetic fields if you send an email to al@wallash.com.

Again, great job.
Al

Thanks for your input.

Yes, that's my thought also, the sparks is the problem.

The meter I'll be getting will work similar to the Trek 520, so I'll do similar tests using that type of measuring tool.

[mk1spitfire]

Lubricatting the main shaft with oil is no more of a band aid than using conductive spray between the belt and the pullies to help bleed off static build up at the very source of electro generation.

Both are areas of maintanace but accept they are not permanent but that is why planned maintance works.

Silicone is non conductive. This will help reduce friction and should help but Graphite spray surley is the way to go, unless as some post's have mentioned a better conductive belt material is made.

Come on Align. We can see this can't you.

Excellent reasearch by everyone.

Very interesting that it's not neccesary the actual arc that is causing the possible shut down but the frequency of the spark in ghz range???

Also the belt must be inducing voltage through the gears as some other videos have posted.

Mk1

[mk1spitfire]

When will the first model Heli be developed that disregards the tail rotor for a pumped air system through the boom?

That should finnish the static issue.


Mk1

[hrosee]

Shawn,

I did basically the same test but I still had static readings at the tail blades even after lubing the belt with silicone.

I then did the ground mod at the front and rear bearings and all is quiet.

Like finless said if you wait for Align to come up with a fix you will never fly. The grounding of the boom to the front and rear bearings and then to the frame appears to be the only sure fire method that always works.

It seems to me that depending on the weather at your location different tests show different results at different times but the grounding always works.

It's just too bad we can't get all metal parts, front and rear, like my 450SE. That would be the permenant fix.

[chichiuno]

Originally Posted by alwallash

Kevin,
(They are immune to the <100 MHz noise from ESCs, though.)

Al

Maybe on the reciveing side, but not on the back side.

[bmlasater]

fwiw...

Why is the 500 the ONLY heli of this design having this big an issue with static...There are quite a few static generators on all model helis...Seems there should be more issues with more brands..I don't doubt that static can be an issue, but why does it seem to affect the 500 so much more adversely than others?? Has to be a reason we're collectively not seeing... No pun intended...

John.

[Finless]

That has been answered many times already... The design has everthing radio related packed in the back and servo wire routing right by the pulley. An arc thus has a higher chance of effecting the radio system.

Bob

[armsmaster]

I'll tell you why the 500 has such an issue... The tail belt material.... The first production run of the 500's are not having this issue. Reason is that Align changed the tail belt.

You may ask how I came to this conclusion? Answer: Easy, if you take out all other possible factors in the equation what is left. "The tail belt material"

[Finless]

Nope not true.... I got a first run and so did Jason Chow. SAME SHIPMENT same helis and belts. He had lockouts I do not ( I lubed my belt day one and I bet he did not and he lives north in a dryer climate. I live near the ocean)...

So this is unfounded....

Bob

[ozace]

I have just started assembling my 500 and after reading all this static stuff it dawned on me as i opened the belt bag. The shiney belt in my kit (i assume all are the same) is something that concerns me. I hope someone finds a replacment belt to try. If i were a betting man, thats where my money would be.

[psindrup]

Originally Posted by Finless

Nope not true.... I got a first run and so did Jason Chow. SAME SHIPMENT same helis and belts. He had lockouts I do not ( I lubed my belt day one and I bet he did not and he lives north in a dryer climate. I live near the ocean)...

Bob

If it was that simple, then only lubing the belt would be the solution to the whole issue ...

And when lubing the belt does make a difference, then belt material could be an issue too.

Just my two cents ...

Peter

[ChasHeliCop]

FWIW.... (the flamesuit smiley is gone)

Ok, I wasn't going to post this cause I am going to get ripped apart for it, but when I was looking for ideas to "debug" a Van de Graaff generator, I found this on "How Stuff Works" I know everyone has said not to use WD-40 because it degrades the plastics and rubber, and I never have, until now. I put it on there last night, we will see how it flys today. To be fair, it is moist here from recent rains, so it's not really a fair test. But WTH, I am willing to try anything at this point, and if I have to replace my belt a little sooner, so be it. I did NOT spray it on thick, I just rubbed it on with a Q-tip on the cogged side of the belt.

http://www.howstuffworks.com/framed....motor/vdg.html

OIL

Oil and VDG machines don't mix. If the tiniest bit of oil gets on the rollers and belt, their surfaces will no longer touch. (Oil touching oil does not generate contact-electrification.) If you must lube your motor bearings, use great care and definitely DON'T use a WD-40 spray can under any circumstances.............


CHOICE OF MATERIALS

What did you use for a belt? Beware, some types of black rubber are conductive and will not work. They're full of carbon, and will fail when installed in a VDG. They short everything out.

[mk1spitfire]

Originally Posted by ChasHeliCop

FWIW

CHOICE OF MATERIALS

What did you use for a belt? Beware, some types of black rubber are conductive and will not work. They're full of carbon, and will fail when installed in a VDG. They short everything out.

what do you mean by this?

[ChasHeliCop]

I found this on the web site listed above for reasons your home made VDG generator may not be working. So, the things they the list to check and NOT use, are the exact things we should be using. The belt material I thought was interesting because if the stock belt is non-conductive, then it would be the ideal VDG belt to use. This would indicate that the use of a conductive belt MAY solve the issue.

[mk1spitfire]

Originally Posted by ChasHeliCop

I found this on the web site listed above for reasons your home made VDG generator may not be working. So, the things they the list to check and NOT use, are the exact things we should be using. The belt material I thought was interesting because if the stock belt is non-conductive, then it would be the ideal VDG belt to use. This would indicate that the use of a conductive belt MAY solve the issue.

Exactly.

Please ask Align why they don't do this.

Someone may get injured by a falling heli ,static belt induced. Safety for one thing. Prize possesion another.

I have always advocated the use of grapite spray which is electrically conductive as an alternative to silicone spray which is not when aplied to the belt.
This carbon spray will bleed off static at the very source of electro generation. Namely between the roller pullies and belt.

The silicone spray will reduce friction which lessens the static build up.
The carbon spray will eleminate all static build up on the belt.

How long either will last when aplied, I don't know.
I believe the graphite spray dries so don't think charged particles fly off as if it were wet.

Roll on conductive belts.


Mk1

[motomanmel]

Originally Posted by hrosee

Shawn,

I did basically the same test but I still had static readings at the tail blades even after lubing the belt with silicone.

I then did the ground mod at the front and rear bearings and all is quiet.

Like finless said if you wait for Align to come up with a fix you will never fly. The grounding of the boom to the front and rear bearings and then to the frame appears to be the only sure fire method that always works.

It seems to me that depending on the weather at your location different tests show different results at different times but the grounding always works.

It's just too bad we can't get all metal parts, front and rear, like my 450SE. That would be the permenant fix.

I would have to agree we all need to ground our heli to go out and fly. I dont feel a 100% when I fly my 500 because of the crash I had due to black out. We all purcased the 500 to fly so let all ground it for now. Lets all bug BOB to do a quick video to help some of the people that are haveing problems and dont understand whats going on.

Once we all have the real fix like New belt, Metal block, so on and so on. Rest assured Align will come out with it.

But until then we can all fly with the ground mod and fly with out having to think is my heli going down today????

[Finless]

Yes a conductive type belt would solve this pretty sure. But Align does not MAKE belts and based on people looking for a replacement "off the shelf" it doesn't look like one exists. Thus would be a custom order for Align. We can hope but I have a feeling we wont see that too soon.

Bob

[warpspeed]

Ergo, torque tube.

C'mon Bob, lean on 'em

[Finless]

It's NOT that they don't want to do a TT it's that they are having issues making it reliable!

Leaning on them wont do much if they cant get it working without stripping gears.

Bob