Power Pack B power supply?

[C130CrewChief]

Greetings all,

Probably an easy question, I'm looking to build up the 3 pack swappable and purchased the Power Pack B. After some time of back and forth I and thoroughly confused and frustrated. I am unsure of what battery size to go with that will give me ample flight time/experience and not burn up everything I just purchased. I'm pretty sure that I gave the FT "Batteries and Safety" as well as the "Power System" video's about 100 more views in the process. I was looking at 3Cell Lithium Polymer in the 1300kah, I looked up the EMAX CF 2822 motor and some sites recommended this as well as 1000kah. What is a better choice and what are you guys running? Thanks for the help.

 

[Craftydan]

1300kAh?!? man I'd love those batteries in the sizes we're using. We'd be able to fly for DAYS!!!!

CewChief, Welcome to the forum (and I hope you don't mind the ribbing -- the unit is mAh: three decimal place shifts in the other direction)

I'd say it depends on what you're flying, but a 1300mAh battery isn't that much heavier than a 1000mAh. While I've got both, I will say I've got/use the 1300's far more. There are a handful of planes the 1300 runs heavy on, but more often than not, I'd rather have the longer runtime than the lighter weight . . . and even then, I tend to fly gliders, which hate extra weight.

Unless you're going with something small, I'd lean toward a 3s 1300.

 

[TEAJR66]

Welcome to the forums.

If you are looking just to fly the three pack swappable's, stay between 500mAh and 1000mAh batteries. 2S or 3S will work. You could start with a 2S 500-800mAh battery on the flyer. By the time you get to the delta, a 3S 1000mAh will be a riot. The 500mAh won't give you real long flight times, but it will keep your All Up Weight (AUW) lower which is better when starting out on those planes. 2S is plenty of power for the three pack.

Another thing to do is check the forums and your local area for any other flyers near you. It is always a better experience when someone more knowledgeable helps you get things worked out right.

 

[dgrigor02]

IMO, it really doesn't matter much for the 3 pack 1000mah will still give plenty of runtime. I like that battery in ft22 and all bloody wonder varations so it won't go to waste. Mighty minis 500-800mah ( since skinnier fuse your pretty limited ), 1300mah is my favorite for 800mm sized warbird planes, 40+" wingspans 2200s pretty common.

Eventually you will probably end up with some 500,800,1000,1300,2200s anyways so whatever you start out with you will probably be buying other sizes as well. I like to just go with whatever size balances out the plane the best without having to use weights. So I collect quite a few and like to have at least 2 of each.

 

[C130CrewChief]

Awesome, this was the info I was looking for! I appreciate the jabs at my mistake, would have done the same, being military and in aviation acronyms sometimes get scrambled in my head lol. Thanks!

Just a side question is there ever a the chance to have to much battery or power (not looking at weight)? Say I use the power pack B and everything is set up correctly but instead I use an insanity large battery. Watching the FT videos I get that mAh is like the the gas tank and the cells are like individual bladders of fuel, but I think my question is about the C rating?

 

[Craftydan]

I figured you wouldn't mind. You'll fit in here just fine

Think of C rating like a fuel line -- the higher the number, the wider the pipe, the easier it is to get fuel to the engine . . . but the engine is still going to draw at the rate it needs and no faster. Unlike fuel tubing, however, the wider pipe comes with significant weight and modest cost penalties. The penalties can be worth it, if you need the current on at least one airframe that you use that pack with, but if not, it's just a waste.

On the flip side, if the engine demands too much, the engine starves a bit and ultimately it can damage the fuel pipe, in this case that's the internals of the pack . . . and you end up with a puffy hot weakened pack at the end of the flight.

From what I've seen in this scale of airframe, the typical slowflyer and sport plane will be happy with a 25-ish C pack. EDFs prefer in the 30-40 range, multirotors prefer in the 40+ range.


. . . but . . .

Keep in mind, while batteries are rechargeable, they're expendable items. They do wear out, so no need obsessing too much about getting exactly the right pack. As long as it's close enough to use, you'll eventually replace it with a better suited pack when it's time has come.

 

[TEAJR66]

I figured you wouldn't mind. You'll fit in here just fine

Think of C rating like a fuel line -- the higher the number, the wider the pipe, the easier it is to get fuel to the engine . . . but the engine is still going to draw at the rate it needs and no faster. Unlike fuel tubing, however, the wider pipe comes with significant weight and modest cost penalties. The penalties can be worth it, if you need the current on at least one airframe that you use that pack with, but if not, it's just a waste.

On the flip side, if the engine demands too much, the engine starves a bit and ultimately it can damage the fuel pipe, in this case that's the internals of the pack . . . and you end up with a puffy hot weakened pack at the end of the flight.

From what I've seen in this scale of airframe, the typical slowflyer and sport plane will be happy with a 25-ish C pack. EDFs prefer in the 30-40 range, multirotors prefer in the 40+ range.


. . . but . . .

Keep in mind, while batteries are rechargeable, they're expendable items. They do wear out, so no need obsessing too much about getting exactly the right pack. As long as it's close enough to use, you'll eventually replace it with a better suited pack when it's time has come.

He always articulates these things so well.

Another thing to keep in mind is that the C rating and the mAh are kind of tied together. A 20C 1000mAh battery can dump 20amps continuous. A 20C 500mAh battery can only dump 10amps continuous. Your motor uses up to 18amps at its highest end. So, a 20C 500mAh will sag and not have a long happy life. You would really want a 40C 500mAh.

Again, if you are starting off with the three pack, my opinion is that the 500-800mAh batteries help keep the weight down. By the time you get to the Delta (it likes more speed), the 1000mAh battery works very well. The 1000mAh on the flyer and nuttball make them feel sluggish (to me). You won't go wrong with a 1000mAh battery and it will take you through the whole three pack. I just prefer lighter setups in the flyer and nuttball.

 

[B.C. FoamWerx]

I have found that 1300 is kind of over kill on the battery life. For a flyer or a delta wing, 1000 is plenty. Also, depending on where you are getting them from, 1300 can be a good bit more expensive. Considering that batteries don't last forever, I would suggest spending the money on other more permanent things.

 

[C130CrewChief]

Defiantly a great response from you guys and it helps a lot. I'll start with the 1000mAh LiPo's in 2-3cell and upgrade later, like B.C. says I need the money for more permanent utilities, like a decent trainer/hand-me-down controller for my 9 year old, and pinching pennies is somewhat entertaining lol.

 

[quorneng]

C130Crewcheif
To answer your question. the battery capacity itself has no impact on the ESC and motor other than how long it will run for.
Battery capacity is exactly the same as the volume of fuel in the tank.

Just a point but with LiPo the rate at which it is discharged, measured in 'Cs' (1 C is the current to discharge in 1 hour) does have an impact on its overall recharge life - the point where it no longer provides sufficient power or capacity.
A smaller capacity battery worked harder will not last as long as a bigger capacity one that is discharged at a relatively lower rate.

The down side is that bigger capacity batteries weigh more so the motor has to work that bit harder to fly (and take a little more amps) so the battery has to work that bit harder too tending to counter some of the benefit of having the bigger capacity in the first place!

It is a very complex problem with a great many variables (that includes how you like to fly your plane!) so it is best to start from a well proven point and take it from there.

 

[C130CrewChief]

Just got my Power Pack in and ordered 2 ZIPPY Compact 1000mAh 3S 35C, for the size and price I figure it's a good starting point, and I won't have to swap leads. I picked them up from HobbyKing (let's see how this goes) and than to support FT, and because HK didn't have any in stock a 2-3 cell basic charger and the voltage alarm. Thanks for the help, I'll keep the thread going with updates, I hope to test them ASAP.

 

[Forster]

Just got my Power Pack in and ordered 2 ZIPPY Compact 1000mAh 3S 35C, for the size and price I figure it's a good starting point, and I won't have to swap leads. I picked them up from HobbyKing (let's see how this goes) and than to support FT, and because HK didn't have any in stock a 2-3 cell basic charger and the voltage alarm. Thanks for the help, I'll keep the thread going with updates, I hope to test them ASAP.

Hey, don't know if you're still on the forum but I ran across your post and wanted to thank you for your service. Like the poster says "Crew Chiefs, because Pilots need heroes too."