Sig Somethin' Extra Electrified

[poowensiii]

Darell,

I'll share a few points to get this discussion going and assume you want to achieve similar performance to what you currently have with glow power.

1. What is the current overall weight dry?
2. What is the weight of the glow motor and tank size?
3. Will you use a battery elimination circuit (BEC)? A good UBEC is about $20 and then you can ditch the recv battery. Recommended.
4. Good sport plane performance is achieved at around 150watts per pound. So if your plane will weigh 6pds then 900w is a good target.
5. Most 900w applications that I've seen use a 5cell pack (18.5 volts).
6. So the watt (900) and volt (18.5) selections drive the amp and KV requirements. For example, 900w / 18.5v = 48.65amps. I'll assume your glow motor is turning the prop at around 10,000rpm. So 10,000rpm/18.5volts = 540.5KV. So a motor with a similar KV, able to handle 50amps continuous, 5 cel lipo, and turn the desired prop size at 10,000rpm will work.
7. I'd also recommend a 60amp esc or larger.

[poowensiii]

Darrel,
Probably. Not sure what servos you're using, but 6amp is probably enough. You could check your servo specs just to be sure.
FYI - Be sure to perform your initial check with a watt meter just to be safe. It's hard to know just how many watts a certain prop will pull.

[poowensiii]

Darell,
Yes you can put a meter in series and measurw the amp draw.
it would be interesting to know the results.I would guess around
1amp stalled.

[Wingnut]

Been doing some reading on this and it appears that current draw depends on stall torque but rule of thumb is as follows.
(Standard servos approx 40-49 oz-in or 2.9-3.5 kg-cm)

For 4.8v....Running current=0.2A, Stall current=0.8A
For 6.0v....Running current=0.25A, Stall current=1.0A


Hope this helps.
Steve