AR7000 almost cost me my fingers

[emilware]

I need some input on the issue i have with AR7000. On sunday i was about to fly my Trex 450 but in hover i noticed that elevator servo flicker a littel. It wasnt doing that on the ground but when i spool up at about 35% TH it starts flickering. So i was thinking that i have a bad servo. I called HH on monday and today got new servo. I nstalled the servo just to find out that the new one does the same thing. So i tried moving the noise cancelator ring on ESC cable closer to RX thinking that is my problem , then i spooled it up slowly. It seemed ok for few seconds and then all 3 servos started flickering, so i quickly pulled back to cut the motor but when i did that servos started extending to the max and back. The head was still spining at about 700 to 900 rpm and my heli started tipping over so i tried puting my hand head top plate to stop it stupid idea i know, but after a second srevos stripped and the blades got hold of my finger. I was able to hold on to it and stop the head but even that the stick was all the way down every few seconds motor would start again while i was trying to disconect the battery.
Thank God that i only brused my fingers. No blood or cuts.
I was wondering if anybody had a problem like that with AR7000 RX.

[MXRACERX43]

Sorry to hear about the injury. Did you bind you RX with the throttle all the way down?

[CeeveeSiN]

AR7000 is a tad large for 450s.. I usually use those on 600 and up birds.
but no never had an issue at all with any of them.
I use 6100s 6200s and 7000s and not had any issues.

why were you working on a hot bird without an engine wire pulled for safety though?
that's pretty dangerous, and dont ever try to stop a crashed bird with your hands wait till it stops itself then approach you are very lucky.

[emilware]

I had this RX for about 8 months now and never had a problem. I used it on venture 30 , in january i got 450 and since i'm not flying venture i used RX on 450.
The reason i worked on hot bird was that there was no problems when the motor was off or disconected. This problem would only start when the motor got about 1000 rpm thats about 35% TH and up. I palced my rx in the back just like Finless in his video and ESC and Battery on the front.
I have no idea what is going on. I'm afraid to use this RX agin. Could this be caused by ESC?

[CeeveeSiN]

gotcha.. glad you are ok man.. that some scary stuff.
i have a friend that lost 2 fingers to a 450.
now I'm a tad paranoid about all helis in general.

if you are uncertain of the RX send it up to Horizon they will test and upgrade its firmware for free.

[emilware]

the only reson why i tried to stop it was that i was in a garage and didnt want main baldes flying and hitting me once the heli hit the floor.

[FireSlash]

Sounds like a bad RX.

There's an easy test to confirm though. Disconnect the motor, and all other servos. Then repeat the process you did previously. If the RX is really bad, it will have the same behavior regardless of if the motor is plugged in or not. Same with the other servos.

If the problem goes away, it could be some bizarre issue with the ESC and the AR7000 being touchy, or possibly the motor feeding back interference through the ESC into the RX... though both of these cases seem bizarre.

You might try hooking a multimeter up and monitoring the voltage going to the AR7000 while it's spooling up. You'll want to have resistance on the motor while you do this, so secure the bird to the ground.

[cbflys]

You may be experiencing electrical interference from the switching circuits in the ESC or the from the motor.

[emilware]

I just tested RX without the motor and it seems ok just like before. This problem would only show up when in hover or spool up with load on the motor. I also tried taking the pinion of the motor and running the heli with out blades spining and it seems ok too. could this be that the ESC or motor is drwaing too much power. My battery packs are good fully charged KING POWER 2000mah 11.1V 3S1P 25C, motor is SCORPION -8, and stock align ESC.
I dont know what is wrong
What should i replace?
I'm running analog SM22 Jr servos and my ESC never gets hot. I afrid to hook it all up and have the same thing happen all over again.
Please help
thanks

[cbflys]

Perhaps if you have a picture of or describe your electronics and motor installation, we could make some suggestions.

Ferrite donuts on the long signal leads going to the RX, keeping the RX and Gyro as far away from the motor and ESC as possible are just a few of the things you can do to help combat electical interference.

[emilware]

i Just took it all apart so taking a picture now would not help. But i placed all electronics just like finless suggested in his video. ESC is placed in front with cables to the motor coming out of the front, the battery sits abve it on the tray with the lids hanging down, AR7000 is as far as back as posible with the satalite recever mounted on side of the tail boom block.
Maybe the pics tha i took few days ago will be enough so take a loook at them. Heres the link http://www.helifreak.com/showthread.php?t=14037&page=63
post number #630.

[emilware]

Any other sugestions guys?

[FireSlash]

http://www.helifreak.com/showpost.ph...&postcount=630

Pictures don't load.

[emilware]

sorry
here are the pics

[Coop]

Some time back my 450 did pretty much what you describe. I changed servos etc. It didn't stop the twitching. On a hunch I sprayed a small amount of silcon spray into the boom. Problem fixed instantly. It came back when I crashed and installed a new belt. More spray and it once again went away.

Trex 500's have had a big problem with static electricity buildup.

Give it a try it can't hurt.

I fly with AR6000 and Castle Creation ESC. I have taken NO steps to separate anything, or sort the wiring. Both of my 450's have flown over 3.5 years and that one instance is the only glitching I have seen.

[emilware]

thanks man.
I will give it a shot.
Will see tomorrow because today i put new HS65 servos and new AR6100. i hpoe the problem will go away.

[raginredneck93]

Had a similar problem last year with my 450. I replaced my main gears with the newer style dark blue ones with the nifty bolt in one way hub, and on my next flight (luckily I was just hovering) I started noticing an occasional "blip" of my servos. It was subtle, all I could see was like a ripple going through my rotor blades in a hover, and only every so often. It was enough to make me nervous, so luckily I kept it in a hover and close to the ground until I worked out the bug. After about 5 minutes of hovering, my heli went brain dead . . . total loss of everything. Once again I was lucky, the motor slowly spooled down, the heli settled on one skid, then slowly settled to the ground. After about 15 seconds it came back to life and I was able to spool it up again, and had full control, but it did it again after about a minute sitting there on the ground with the rotor spinning at about half stick. I decided it must be a bad rx (AR6100), so I threw in a different one. Next flight - same thing. An occasional ripple in the rotor, then a total shutdown. Granted, mine didn't go ape like yours, but it was exhibiting some mighty strange behavior. I moved wires, tried this, tried that, some things seemed to help, but it would still do it after about 4 or 5 minutes of running. Basically it cheated me out of a good bit of flying last summer because I couldn't figure it out and at the time it was the only heli I had.

The problem? Turned out to be the fact that the nifty new dark blue gears are just a whisker larger than the old style white or light blue ones, and it was just enough of a load to overheat my ESC and cause it to shut down. Thanks to my good friends at Heliproz for pointing that out to me. I have no idea why the BEC shut down and cut power to my rx instead of just shutting down the motor, but it did, and it scared the hell out of me. Luckily I'm a chicken and always spend the first few flights just hovering whenever I change anything because if I'd been in forward flight when it lost its mind, things could've gotten ugly.

The fix? Why, I got an SE V2 frame of course. I wasn't going to go back to those lame old light blue gears after all. Oh, and I got two more helis to fly this summer, so if one gets recalcitrant I can just fly another one. Seemed like good logic to me. Tossed a Scorpion motor and ESC in the 450 too just for good measure, and now it flies oh SOOOOOO sweet compared to my old setup, and so far, no more radio glitches. I can't believe how SMOOOOOOOOOOOTH this bird sounds now either. What a difference!

In other words, check your gears, tail belt, bearings, ect. and make sure everything is spinning free, cuz Spektrum stuff gets wacky with low/intermittent power, and that can happen with just a little bit of additional drag on the spinny bits.

[emilware]

So today i finished putting my heli together. I installed new HS65 servo, new AR6100, sprayed oil into the tail boom, moved all the wireing and guess what. The same thing happend, but this time i was able to set it back on the ground. I was so mad. But this time the new RX AR6100 had the new firmware v1.6 with quickconect and showed me the problem. The rx startem blinkig meanig there was a short drop in power to RX. So i knew it had to be the ESC (i'm using stock 35a align) or the motor (scorpion -8). I didnt have spare ESC but i had the original Align motor so i decided to put it in. Next flight was great. The problem went away. It was the motor all this time causing voltage drop for BEC to RX.
I'm done with scorpion motor.
I hope i will be able to send it in to get it tested. I also noticed that the scorpion motor was making lot more noice than align. I only have about 6 flights on it and it was load like that from the beginig.
NOW I CAN FLY AGAIN

[raginredneck93]

Does your Scorpion motor have a bad bearing? I wouldn't think so after so few flights, but it could've had one goofy from the factory. My heli was exactly the opposite. It always sounded a little squeaky with the Align motor, but now it hums like a well balanced . . . . um . . . . . spinning thing. I've read all over the place on here that the Align ESC can be a little iffy with a Scorpion, can't see why with the 8 turn since it's about the same kv, but that's what people that know a whole lot more than me are saying. I went with the 55 amp Scorpion ESC on mine. I know, 55 amp is a bit overkill for a 450, but A - it was available, and B - according to the specs it's only 3mm longer than the 45 amp, and just a smidge heavier. Was still a bit of a shoehorn fit in the 450 frame, but I was able to get the CG right, the wiring mostly concealed and out of the way, and the wireless remote control programming is the bomb. Waiting for warmer weather so I can try it out a little more thoroughly, but so far I'm pretty impressed. Sorry to hear that you don't share my enthusiasm. Hopefully if it is a dud, Scorpion backs up their product and makes it right. I for one would be interested in hearing how they deal with it.

[VerticalDave]

What Scorpion motor are you using??

You never want to use a motor with a higher amp rating than your ESC. This will cause your ESC to send all available current to the power hungy motor and starve everything else like your servos, gryos and RX.

Dave