Please help...electric setup..
 

Hi,
I am trying to get into electrics but need advice on my initial setup:

I have a Cermark New Timer (parkfly/Floater) I have put a mega brushless in (ACn 16/15/3) = 480 speed, had a spare Castle Creations PHOENIX 35 amp programmable brushless sensorless speed control.
I have a li-po 2cell 2,000mah which just fits, the 3 cell is too big to fit.I have fitted a 6" x 3" Graupner Cam folding prop.Would the above be a good set up?

Plane Dimentions: Wing..56inch....Wing area..33sq inch....Length..34 inches....weight..21 ounces.

I TRIED A 7 CELL 1000MAH NIMH SUB "C" PACK AND IT GOT SO HOT IT MELTED THE SHRINK WRAP AND THE BATTERIES GAVE OFF A SWEET SMELL.

I have good quality lipo charges and a Whatt meter (Astro Flight) as well as the PHX-LINK USB interface by Castle Creations.

I would be gratefully appreciate any help. I need to get in the Air.

RE: Please help...electric setup..
 

No doubt. I know many people in the area with Projetis running Mega 16/15/3 motors. They're using CP1300 NiCd packs, which are VERY robust, and those come out HOT HOT HOT! I'd imagine those relatively tiny NiMH cells would go thermonuclear :(

The long and short of it is, you're drawing way more Amps than the battery can handle. You've got several alternatives to get things tamed down:

1. Gearbox and a larger prop.
2. Smaller direct drive prop.
3. Fewer cells.
4. 16/15/4 or 16/15/5 motor.

The 2-cell LiPoly will have the effect of #3, being closer to 7 NiMH cells in practical applications. However, you don't specify the brand and model of the pack(s) you have. That's VERY important. One manufacturer's "2000mAh LiPoly" might be able to hold up to the abuse, while another will overheat and turn into a lithium sausage inside your airplane, possibly catching fire in the process. Yours need to hold up to 30 Amps. Look at the "C" rating on the pack. Multiply the C rating by the capacity of the pack to get the maximum Amps it can handle. You're looking for a pack that's rated for at least 15C.

RE: Please help...electric setup..
 

Hi Matt,

Thanks for your reply.

Battery pack 2,000..2 cell kokan

Regards
Chris

RE: Please help...electric setup..
 

Hi again Matt,

Sorry to bother you.

The 2cell...2,000mah is rated at 15c

Kindest Reagrds
Chris

RE: Please help...electric setup..
 

I'd second Matt's suggestion ... New Timer isn't exactly a pylon racer; you need to either gear it or switch to a 5 or 6 turn Mega (imo I'd imagine 7 or even 8 turn would be better). You can get sample prop/amps/cell count applications over at megamotorusa's website.