Problem with plane motor

[shoyn]

Hi Bros would like to consult you all on a motor problem. When I was flying my cessna, the motor suddenly stopped working in mid air, but I still controls of the aileron, rudder and elevator. My set up is a 40a hobbywing esc and a 1350 kv motor. I got a feeling the esc is too much. My other set up is a 20a esc and a 1350 kv motor. Tried it on the same plane. I don't think the receiver is faulty cos I tried it with my other plane but such an incident did not occur. Would be thankful if anyone can help mr resolve this
problem.

[joe yap]

Basically, an ESC with higher rating is safer then lower. Your ESC is doing exactly what it is design to do. In event of excessive current draw or ESC overheating, it'll cut off the power supply to your motor but yet continue to supply power to your radio equipment. It should be one of these conditions that you are experiencing with your setup.

However, it is best for you to provide us your setup in order to zoom in to the answer, instead of us giving you a big 'blanket' of solutions for you to filter out.

Let us know your battery voltage and capacity, motor and ESC size and ratings. The best information will be the actual current draw measured. If not, at least the prop size for rough estimation.

[shoyn]

Batt voltage: 11.1v 20c and 1300mah. Not too sure Of the prop size, but I meaured the diameter is 10 inches. And the blades are angled downwards. Btw when I throttle up, the motor keeps jerking then suddenly I see smoke and smelt burnt electronics.

[joe yap]

10" !!!! Way over propped! Look carefully at the root of the prop, it should have some figures to tell you the actual prop diameter and pitch. I would estimate that your motor is only capable of drive up to an 8" prop on 3S. Do you have the brand and model number of your motor? If you can provide these details, I may be able to recommend the range of prop sizes.

Your battery can safely pump up to 22.2amps maximum.

Judging from what you mentioned, you have already overworked your ESC, motor and battery pack. There may be some permanent damages already, but may still be good for your Cessna.

BTW, selecting the wrong props is one of the most common causes of burnt motor/ESC or battery pack.

[joe yap]

By the way, if your motor is still jerky even with a much smaller prop, you may have a burnt coil,wire in your motor.

[Shayne]

I tried it without prop, it still jerks, most probably the motor is burnt out. Btw how do you know what size prop is suitable for a motor?

[joe yap]

Just some estimations from your report. You mentioned a Cessna, and ther are a lot trainers marketted under 'Cessna' are realatively small. You also mentioned about the 1300mah 11.1V (3S) lipo battery. Most ARFs models have rather limited choice of battery pack sizes and I assume you can't go very wrong with the choice of the battery.

At this size, the motor you use are most likely to be a outrunner with about 28mm diameter and most outrunners at this size with 1350Kv can only manage an 8" diameter prop size at the most on 3S setup. For a 10" prop with this motor, you can only use 2S (7.4V).

Before you spend any more cash, swap your motor or ESC with a spare unit to try out first. I can be just a bad connection between the ESC and the motor. BTW, you are still not giving enough informations for people to help you further.

[shoyn]

Ok. Will now try to list out the electronics i am using.

TX: Spektrum DX6i
RX: AR 6100e
esc: 25A ESC
Motor: turnigy aerodrive c2826-1350
Prop: No prop

Tried it without prop and it still jerks.

[f22]

hi

Ok. Will now try to list out the electronics i am using.

TX: Spektrum DX6i
RX: AR 6100e
esc: 25A ESC
Motor: turnigy aerodrive c2826-1350
Prop: No prop (8x6 / 9x6)

Tried it without prop and it still jerks.

Bro, try to re-soldier all your wires from esc & motor, suspect broken wires, if not your motor is gone..

[shoyn]

I got a feeling my motor gone. Got chao ta smell....

[joe yap]

See this; http://unitedhobbies.com/UNITEDHOBBI...idProduct=4908

This motor can only take 7x4" on 3S, 10" prop has just killed it probably.

[shoyn]

What kv motor can use 10" prop?

[viper1990]

If you're using 3s, and a 10inch prop. Normally i'll go for 900kv-1100kv motors.

[joe yap]

Why do you want to stick to a 10" prop? This little plane has very little ground clearance for such a big prop, and it can mean that you'll need to stock up plenty of spare props.

[Jack_Chen]

very interesting, I happen to be doing some spring cleaning and got the my Thunder Tiger Sparky 400 off the wall.

It has a Hacker brushless motor - A20-20L. 1022 kv, spins a nice 10x4.7 on 3S.

maybe you should opt for a 9x5 prop type motor or go for a 3 blade GWS 8x4. Then you can have some ground clearance.