Wizard quad going crazy

[mitchb2]

Hello, I just found this forum.

I'm brand new to quads.
A few months ago I set up a Wizard x220 with FlySky FS-i6x transmitter.
At the time I tested the quad and it worked fine. But I realized how hard it was going to be to fly so I spent some time on the sims.

A couple days ago I figured it was time to fly it.
I took it outside, connected the battery, armed it...and it went nuts. The two front motors went full-throttle, the quad flipped over and broke two props. Fun times.

I brought it in, removed the props, flashed the latest Betaflight, and still no luck.

When I arm the quad the motors go on and off randomly. Some twitch, some spin up to high speed. They start and stop and beep.

I followed Joshua Bardwell's setup video on YouTube.

Here's what I know:
- Latest Betaflight
- Board alignment good...270 degrees
- Receiver bars respond to transmitter correctly
- Motors calibrated and work fine with the sliders in Betaflight, motors spin in correct direction
- Props installed correctly (when they were installed)
- 3D model in Betaflight follows movement of quad correctly.

What can I look at next?

Thanks!

 

[ElectriSean]

You've pretty much covered everything it can be, double and triple check everything...

 

[mitchb2]

EUREKA! Minimum throttle setting was supposed to be 1035, and I made a typo and had 135 in there.
Made that change and now when I arm all 4 motors idle as expected.

Time for props!

 

[mitchb2]

I have my low-voltage buzzer set to alarm at 3.5V.

I went out with a fully charged 3S 1300mAh and it only lasted about 10 seconds before alarming!
I landed and the buzzer showed that the lowest cell was still 3.8V.

Is that normal?

 

[PsyBorg]

You sure that pack was full charged at 4.2v per cell?

Yes it kind of is normal and no its kind of not. Quads are power hungry as they spin 4 motors. This can cause serious sag on lower C rated batteries. You should not be flying anything less then 65c for cruising 80C or higher for freestyle and even higher if seriously racing. The buzzers will trigger the second you go below the set level and will 1. annoy the bejeebus out of you. 2. It will seriously hinder normal flight times as you will be coming down way too early to get the most out of your packs.

If the quad has an osd I would track MAH used thru that as well as voltage. You will get a feel for how low you can take them without damaging them. I use on my radio the %timer and have figured out how much time I can use the batteries for much more accurately. It goes by throttle percentage and will vary by how much or how little throttle you are using. For example if I am cruising around with my normal timer for my 3s Gremlin set to two minutes and am easy on the throttle I can fly for 6 -9 minutes depending how much crashing and walking I am doing. If I hit it hard I can take that flight time down to below 3 minutes on a 450 mah 45c battery.

Your Wizard is much heavier then my 146 g Gremlin so you will have a more realistic timer around 1:20 ish on decently c rated packs. you just have to fly and adjust up or down depending on your batteries. Having the voltage in your OSD will help greatly dial this in and between the two you can account for sag and recovering times when you are not flying hard.

 

[mitchb2]

Thanks for the great info. The pack I ran today was a pack I had bought for my Parrot. The reason I used it was that I got some advice about starting out with 3 cell packs.

I also have some 4s 1500 45C packs that I haven't used yet. I'll see how those work tomorrow. But I'm still worried that I ruined them by storing at full charge.

 

[PsyBorg]

How long were they stored fully charged?

 

[mitchb2]

Many months! I would actually take them out of storage and top them off because a copter guy told me to.

 

[PsyBorg]

Fly them a bit to get the stored power levels down even if its just a hover in the kitchen or living room. Get the packs chemicals stimulated. Then they should always be stored at 3.8v per cell. I have had several packs that got lost in the shuffle sit for several weeks at full charge and they have no issues. I think it is more a safety thing then a truly "bad for the pack" thing. They only dropped .03 v per cell on average. Its temperatures that do the real damage to the cells.