Is this enough battery for the load?

[Blip]

I want to use 2 NimH battery packs each rated at 6 volt x 2700 mah for a new build.
There will be 6 x 8511 servos and 1 x 8711 rudder servo along with a small digital throttle servo.

Do you think the 2700 mah battery packs will be sufficient for the number and type of servos above?
I know there are larger size packs out there but want to keep the weight down without adding over sized packs that are not needed.

In case anyone needs to know, I usually fly 3 x 15 minutes on a flying day.

Thanks

[3ddd]

yes they will work just fine,i have used that size packs alot in 30% planes

[Blip]

Hey thanks 3ddd. I messed up on my post it should have read 6 x 8511 and not 4 as I originally typed.
Hope this still means the battery packs are ok?
The planes a 35%

[cliff600]

I think it would be o.k. too, but the end of the last flight would concern me a little. 15 min. is a long time to be pulling alot of juice from the batteries. What kind of radio do you use? If you use Spektrum, the last thing you want is to let the battery get too low and have a brown out. Abuddy of mine has almost the same setup in a 102 QQ Yak, but he usually flies 6-7 min flights. He has never had an issue. The more I think about it, you should have no problem.

[3ddd]

ok no problem,just keep a load tester handy as different types of batteries unload juice at a different rate,check them after three flights and devide to see how many mils you pull then you will have a better idea

[Andrew Gilchrist]

If you want reliable seervo packs go lipo - the weight is 1/3 the performance of even small packs eats nickel alive
and the relaibility of the battery is near perfect until its days are at an end. This will be several times the life of Nimh and the while nickel packs will work poorly for most of their lifespan, the Lipo will offer power within a few percent of the new specs

ALso forget the so called reciever packs use power packs 20C and up and the servos power will be creamy smooth.

[classclown]

Blip, may I ask, what kind of 2700 NIMH cells are you thinking of using? Sub C's right? Just want to make sure, there are 2700 AA cells out there too, and you do not want to use those. You said 6 8511's? Not 8411 or 8611??? Make sure you cycle the packs 2 or 3 times, jot down how many milliamps go in and come out and go in again. If the numbers are not consistent, throw 'em away. Throw a load test on each pack before every flight, until you know the packs.

[Ralphbf]

I'm using 2-2300ma battery packs and 2 HD charging switches.
http://www.all-battery.com/6v2000mah...ctor11106.aspx

I was assured it was the best way to go by club members who are flying simaluar craft.

Are you saying this isn't a good setup.

5 - Hitec 427bb
2 - 1/4 scale servos on elevator and rudder. I'd have to go look to see what they are.
1 - HS422
1 - Futaba FP-R129DP Receiver

110" Mr Mulligan bashed into a DGA-15 Navy air ambulance

[Ralphbf]

I just contacted customer support to find what the max. current draw is for these packs.
They should get back to me tomorrow by email.
The wire is 22awg.

I know the receiver will handle 12 amps.

Don't know the current draw of the plane.

[Glacier Girl]

Ralphbf,
Looking below the ad you posted was the separate cells that make up the pack I believe. Spec sheet on the packs is here. http://www.all-battery.com/datasheet/2300mah.pdf

Not sure if it's a typo, but it says a rapid charge is going to take nearly 2.5 hours and a normal charge is 15 hours.

I'd go with a lipo and regulator myself. More capacity at same weight or less, no real drop off like a regular cell,no topping off before a flight. Lipos can go days/weeks/months with very little loss of charge.

I fly all electric birds, we can get away with built in battery eliminators in the motor controllers, or stand alone units if the amp draws are high to run the electronics. I only have one bird with an rx pack, and only use it as I needed the nose weight.

That's too nice of a bird to take a chance on. Best of luck to you.