awesomerc

If anyone can help my buddy, chime in...Here's what he wrote:

I am finally getting time to set up the Electric Agusta heli (Graupner 60-sized with 30 3300NimH cells!). Don't call me an idiot, but this is what happened:

a. I was spooling up the motor (no main blades on) and I was flipping the Throttle hold switch to shut it down. The T-Hold was set to -.05% so the motor would just shut down. (JR 8103 SPCM)

b. I decided to see where the throttle trim was kicking in so I advanced it. There was an audible tone as I increased the trim and I wasn't sure if that was the ESC kicking in or what. Well, I saw smoke and shut the system down.

c. I would say it toned for 3-5 seconds before I shut down. I tried to determine where the smoke was coming from and I must say I think it was the motor but I'm not sure.

d. I let it cool down and spooled up with no trouble. My question here is whether there is a way to test the integrity of the system. (I haven't even flown the damn thing!) I don't think it was the ESC because it wasn't smoking directly. I have it up front and in mounted on the side of the servo tray. The smoke was coming from deep within the fuse (I had the lid and windscreen off). If it was the motor, could it have been from a conflict between T-Hold and the advancing trim lever? That doesn't make sense to me because on T-Hold I would normally have pitch control with the same channel.


Am I up the creek before I have flown it? Did I ruin the motor? Help!

staggerwing10

My Feedback: (1)

did you break in the motors throughly before running them in your heli?

awesomerc

It turns out that the motor was NOT broken in and did not have the connecting diode. The builder forgot this and I didn't know about it.

The batteries fried a bit, but are OK and the motor is fine on close inspection.

Still don't know what happened to put a huge load on the batteries.

staggerwing10

My Feedback: (1)

it must have started the motor the wrong way and used a huge current. glad i wasnt there. to break in your motor (this is the best way ive read) run it at half speed in a glass of water for a few battery discharges, the water will turn cloudy with some of the stuff thats been gound off the brushes so that they turn smotthly. ive broken in all my motors this way and have had not problems at all.
cheers