ESC Intermittent “Glitchesâ€

[Marc]

Hey guys!

I’ve been having a ball with my Mini Titan 325v2 since I repaired it and upgraded the tail servo to a larger unit. I’ve actually had the same main rotor blades on for more than 2 weeks now! That’s a BIG improvement

Today was a nice day and I got some flying time in and I started to notice about half way through my flights that I’m getting either an intermittent, burst of power and the heli shoots up or a loss of power and the heli falls. Now this happens over a split second and only once or twice during the flight, but always after about half way through.

My initial thought was I was having radio interference, but it only seems to be affecting the throttle/pitch as the heli always goes straight up or straight down. So my next thought is ESC. Since it happens half way through the flight I thought it might be the controller heating up excessively. I have the stock 40A control that came with the kit. Does this sound right to anyone? I don’t have another that I can swap it with to test and wanted to ask before I went and bought one.

Thanks!

Marc

 

[Tony]

Next time it does it, land the heli and check the voltage on the battery. If it's lower than 3.7 volts per cell, or 11.1vDC total, you may need a charge. But, that shouldn't cause it to do this. If you are running an FM system, you could be picking up interference. If it's a 2.4ghz system, make sure you are not pointing the antenna directly at the aircraft. If all of that is fine, and you know it's not a radio glitch, your bec in the esc may be trying to go out. And there is only one way to test that lol.

Good luck and let us know what you find out.

 

[Marc]

Next time it does it, land the heli and check the voltage on the battery. If it's lower than 3.7 volts per cell, or 11.1vDC total, you may need a charge. But, that shouldn't cause it to do this. If you are running an FM system, you could be picking up interference. If it's a 2.4ghz system, make sure you are not pointing the antenna directly at the aircraft. If all of that is fine, and you know it's not a radio glitch, your bec in the esc may be trying to go out. And there is only one way to test that lol.

Good luck and let us know what you find out.

So this morning I got some calm weather again to fly a bit, the first flight/battery I didn't see the issue the whole flight. The second and third battery I did see it, both times it seem to be about 4 minutes into the flight. I do have an FM system and that's why I first thought of interferance, but it just seems to only happen once things have warmed up. I sat outside with the transmitter and heli setting on the ground but powered up for 15 minutes and watched it for twitching, but there wasn't any. I went ahead and flew and sure enough I got the quick loss of power. I didn't test the battery voltage (didn't check the forums until afterwords), but I did continue to fly it without another issue until the esc lowered rpm and I knew it was time to land. These are new 2250mAh 45C batteries and seem to be taking about 1800-2000mAh with each charge so I don't think they are to blame.

My Dad has a 60amp E-flight esc he said I could use that should be in good working order. So I'm going to hook that up and see what happens tonight... I'll let you know.

Oh I also picked up a thermal heat gun (need for another project) and I'll get a read on that esc when it happens.

 

[Tony]

Temp the motor as well when you check the ESC. You are correct in it doesn't sound like the battery. a 45c is more than enough for that heli. I would take your dad up on the ESC. It's a little heavy, but will let you know if it's the issue. I don't think you are getting an ESC glitch, it sounds like a cyclic glitch causing all of the servos to move and lower or raise the pitch. I'm thinking internal bec or Rx. But, we will have more to go on the next flight when you put the 60a ESC on there. Let us know.

 

[RandyDSok]

Cold solder joint on the bullet connectors between the ESC and motor are actually pretty common... even on high end name brand components it's been reported.

Because of that, many pilots will direct solder their ESC/motor together... while that is a sure cure fix... I still like to keep the bullet connectors myself.

You can easily fix these by getting some heat shrink tubing ( to replace what you'll need to remove ) and reheating up the solder joints. If you don't already have one... you'll need at least a 40w - 60w soldering iron and some rosin core solder. Just heat each bullet connector solder joint up until it starts to flow ( it gets real shiny ) and that is it... heat shrink it back when done.

BTW... don't simply cut off the connectors and put on new ones... the wire itself is usually coated with a varnish and is a bugger to clean off well enough to get a decent solder joint. If you had already cut off the pre-tinned ends... then this is even a more likely cause.

 

[Tony]

The only thing that I could add to Randy's post is get 60/40 rosin core solder.

And I have never had an issue cutting off the ends and retinning the wires. Usually the wire that is used on these batteries and ESC's is pretty clean, and I have never had a bad joint from them. With that said however, due to the lack of quality control, there can be crap on them that would cause the solder to not stick to the wires. if I ever have to replace the wire, I always use Ultra wire, at least I think that is what it's called. You can get it from any LHS.

 

[Marc]

I only just got time to test out the 60a esc and I have had nothing but problems with it. It has different timing settings and I might not have the right one for this type motor. When I give it just a bit of throttle, the heli sits and spins as if the tail rotor isn't doing anything. So I decided to switch back and temp out the motor and esc when the problem happens. Same sort of thing happened again. Flew the first battery without any issue, right about the 4 minute mark it showed up. I shutdown and temped the motor at 115F. That doesn't sound too bad I thought so I powered back up and flew around until it did it again and this time I temped the esc... it was around 200F. Now I don't know if that's too high or not for sure, but it sounds like it.

So I did some web searching and found somewhere that if you have lessened your pitch curve to tame the heli down for learning purposes that you could actually overload your esc and or battery (I would have thought it would have lessened the load). Since I've gotten a fair amount better at tail in and left and right side hovering I've been flying it around and not just hovering ( I think I've been doing this after the first battery). So I think that's what happened, I believe my pitch curve before was 55,60,65,70,75 and I'm not sure what my throttle curve was, but it didn't go over 85.

I've changed my pitch curve to 40-75-100, which is giving me a pitch angle of -2-+5-+10, and the throttle curve to 0-45-65-85-100. This is what the manual for this bird says is novice settings. I have had two flights since I made those changes and I've not seen the problem. The esc temping around 120F both flights.

Batteries just finished charging... time to finish up the testing

Oh, I forgot to mention I did cut the heatshrink tubing off both sides of the bullett connector, motor and esc, resoldered and put more tubing on, it looked ok, but it didn't take too long to be sure. That was before I flew today so that wasn't the problem.

 

[Tony]

Yeah, that ESC temp was way too hot and is causing your issues. Let us know about the next flight.

 

[RandyDSok]

The "varnish" I was talking about is usually only seen on the motor wiring that comes straight from the windings... It actually has a name and you can buy it from Radio Shack even... I just can't remember what it is called anymore.

Old age claims yet one more memory...

 

[Tony]

OH, yeah now I know what you are talking about. It's an insulator to keep them from shorting out against each other. PITA to strip away when I used to wind my own modified motors way back in the day lol. But yeah, you just don't even think about trying to solder through that stuff. I'm sure if you could wear it, it would stop a bullet lmao

 

[Marc]

So I've had several flights in now since I've moved the throttle and pitch curves to the novice settings in the factory manual and intermittent loss/gain of power is gone. Also now that I'm venturing higher in the air its nice to have some negative pitch.

Thanks for the help and suggustions, I think we can mark this one as solved

 

[Tony]

Great deal Marc. I'm glad that not only we could help with your issue, but that you are getting more and more confidence in your flying. Hope to see a video of your progress soon.

 

[Marc]

Great deal Marc. I'm glad that not only we could help with your issue, but that you are getting more and more confidence in your flying. Hope to see a video of your progress soon.

I need to get some kind of hat cam or enlist my son

Sent from my SPH-D700 using Tapatalk

 

[Tony]

I like my HD Keychain cam. When it's not overheating that is lol.