Stock Motor Amps

[hrtpaul]

Hi Guys. I've had a look through the site but I can't find what I'm after. Does anyone know how many amps the stock SC LP motor can take? Just not keen on burning it out just yet. Thanks guys. Stay right side up

[Dillzio]

Hey mate,

I recall looking for similar specs a while ago, the closest reference I could find was this:
supercubclub.proboards.com/index.cgi?board=batt&action=display&thread=1831&page=1#11684

Unfortunately, it doesn't take any measurements with the super cub LP stock prop, but the closest size suggests that a 10x6 (master airscrew) prop will use 12.5amps at full throttle. Further down, it says that the stock 10x8 prop uses 18.37amps.

The stock 10x8 prop from the original super cub (which is also recommended for using floats) is notorious for burning out the stock ESCs and motors if it's left at WOT for long. This suggests about 18a as an upper limit, but if you don't want to be replacing your motor every few months you should probably keep it below 15a. Even with running a 10x6 prop, using about 12-13a, I wouldn't expect a stock 480 to last more than a couple of years with regular flying.

Thanks again for your old ESC/receiver by the way, unfortunately though there hasn't been a big enough break in the wind to go flying

[flydiver]

That question is brought up all the time. Unless you have a wattmeter to measure it yourself AND know the specs of the motor the information if of little value.
It's like having a car without a speedometer and speculating on how fast it'll go.

There are no specs for the motor, HZ will NOT give any for ANY of the Cub electronics, and very few new fliers have a wattmeter or even know what one is.

What we do have is some workbench + field experience knowledge that is somewhat useful. The link Dillzio gives you is about as good as it gets. If I were to guess, I'd call it a 13A motor.

Without that wattmeter (or similar tool) you don't have any way to measure it. All you can do is throw props at it and with the WIDE and NON-standard variation in types and style of prop this is somewhat haphazard also. That's why a few props get selected, they have worked.

You might read the 3 posts in this site about props for the SC:
www.ampaviators.com/

Hmmm, says [Under Construction]. Hopefully he's redoing it. He had some good info and was a good resource. Check it once in awhile.

[Dillzio]

This is a pretty good reference:
www.youtube.com/watch?v=ZBVJQ3ZsD1M

Indicates that a 3s lipo even with a 10x8 prop only runs at 11amps. This differs widely from the 18A quoted in the link I posted above.

[flydiver]

An associated link from that video:
Super Cub with GWS Hyper 10X6 and 3-cells Li-POLYs
www.youtube.com/watch?v=yUdBTSlTWAM&feature=related

Pulled ~7.5A @ 10.14v on 3S.

Sure are a lot of variable results testing this thing.

The one concern I have with the link Dillzio posts is the guy says it's an old lipo and it is only 10C indicating it may not have the ability to feed the system up to demand. You can easily see this in the performance gain of a new battery vs identical old tired battery.

Edit- relevant posting on old vs new lipo-double the output:
www.wattflyer.com/forums/showthread.php?t=51921

The results are still a far cry from the 18A seen in the first post.

Old motor? Tired lipo? Both? Lousy original connectors? They have high resistance and the voltage drop goes up as power throughput increases.

Ultimately it looks like the upgrading Cub owners are left in a quandary, which prop to use? Go for power, go for safety/longevity. I know what Duck would do. ;D

Does anyone have a stock LP prop and wattmeter for that reference? HZ would not put a prop on that would subject the system to repeated failure and the grief that they would then get.

[Dillzio]

Yeah, his battery did seem pretty crap. He said it's old, and you could see on the wattmeter that it got down to 10.2 volts at full throttle.

What do you think of this as a cheap and cheerful "wattmeter"?
www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=8319

[flydiver]

Cheap, sloppy (Unit is accurate to .5A). Better than nothing, which is what most folks have. It's like a dim light in a dark room, better than complete darkness.

HeadsUp was selling them for awhile. High failure rate, lots of problems with accuracy. He's not carrying them anymore which I count as telling.

(Real) Wattmeter is the best and most used tool in my box after my charger.