spiral_72

My guy at the field bought a H9 Cub. It's huge and a very impressive plane. He's having problems with current drain from the ignition system.

I saw an ad for a prop shaft mounted generator that put out a DC voltage to run things or charge batteries on a plane. I can't find or remember where I saw it. I've been on Google and on the forums. It was $99 and come in a pack. I saw the think in a magazine best I remember. I think it fit .60 - 1.20 engines or something. I found one made by Sullivan but it's quite expensive, and one called the "Jewel" made for helicopters.

Any ideas?

ChuckW

I've only seen the Sullivan generators but I'm sure there are others out there. A cheaper option might be to get a larger capacity ignition battery or maybe run 2 or more in parallel.

Flying freak

If hes got the cash go all a123 batteries never a problem no regs and they can supply 60c burst (30c constant)

bbbair

If the fellow is having troubles with the current drain ā€“ Iā€™d suggest he finds out why.

It will be a servo that is humming, not correctly centered or too many servos etc. After that the solution is to get a higher capacity battery ā€“ much less expensive and less weight to tow around that an on board generator.

spiral_72

Nah, the ignition has it's own battery. Many people have complained about the ignition hogging so much current. I guess Horizon or Hanger 9 is looking into it. But for now, he's kinda stuck.

I believe he's running a 1600mA 4.8 battery for the ignition. It'll suck dry in about 10 minutes.... Ok, not completely dry, but low enough to worry about. That's not even a tank of gas! I mentioned running two on a y-cable, but that still 20minutes with 2hrs of charging.

The Sullivan is still the only one I've found, and I haven't even found anyone who sells it yet. I used all the "where to purchase" links on the Sullivan website.

Guess I'll keep looking. An extra battery is kind of a temporary fix really. Maybe two 2500mA batteries. I don't think the plane will care about the extra weight. It's huge!

I'll look up the a123 batteries too. I'm not familiar with those.

ChuckW

You might post this in the gasoline engine forum. I remember reading something there once about using a different ignition on the G20 that uses less battery power.

DMcQuinn

My Feedback: (13)

Spiral - it's almost impossible to drain a 1600 mAh battery in 10 minutes. That implies it is putting out 10 amps continously for 10 minutes. Has he checked the battery with a metered discharger?

broke_n_bummin

How old are these batteries? If they're NiCd batteries, it is very possible that they have created the dreaded "chemical memory" and will only allow the battery to drain so far. Invest in NiMH batteries. I would use a minimum 6V 2100 MaH. Also, cycling the batteries will add to their life (even NiMH).

spiral_72

Thanks, I'll do it. It really is a nice plane.


For all: Thanks for the posts. I really don't know how old the batteries are. I was under the impression they were new.

My buddy has flown the plane once. He's been working on this and planning for a month (or longer) now. That's a long time for an ARF! He didn't take any short cuts. After the first flight, there was an obvious problem with the ignition current draw. He found some reviews for the plane and confirmed that this was a problem. That's when another guy and I mentioned the on board generator thing.

I'll post this on the gasser forum and let him know about the Sullivan unit. I still haven't found a supplier for it yet. Dern!