Solved What mAh should I use?

OliverW

Legendary member

OliverW

Legendary member
Looks good! Where were you able to find the full picture for the ESC? It didn't show on the web page.
That was an adapter so you can use the battery you want with the esc you want. It makes it so you don't have to do soldering for the battery or esc
 

FDS

Elite member
Just change the plug. Pick a battery plug you like and then put that on everything. I use XT60 for all my planes and bigger quads, then XT30 for sub 250’s. It’s far easier than using adaptors. Plugs can easily be had off eBay or similar.
When changing a battery plug, only cut one wire at a time and fully solder and insulate it before going onto the next one. If you cut both battery leads you make a short and that’s not good.
 

quorneng

Master member
RC Soarer
Just to help for the future mAh (milli amp hours) defines the capacity of a battery which indicates how long you can fly for before it will be exhausted. More mAh for longer duration but there is of course a down side. Batteries are heavy so the plane will use more power to fly so negating some of the duration benefit and the extra weight will make it a bit harder to fly.
The plan does suggest 800 to 1500 mAh 2s battery so 1300 is within the recommendation although towards the heavier end.
Selecting the best battery, motor and prop combination is not that simple as there are many interrelated variable and to a degree depends on your preference on how you want the plane to fly. It is therefore always best, at least initially, to keep within the recommendations.
 

FDS

Elite member
It’s also a good idea to know how much battery weight you will need to balance the plane without making it too heavy. I pick my battery based on keeping the overall weight to an absolute minimum as you will gain duration in efficiency instead of putting a bigger battery in and flying faster to maintain lift. Once I have built the plane I see where the balance is and how much weight I need using a common battery from my store. If it’s pretty close you can usually tweak the balance using the location of the battery and electronics.
If you are starting completely from scratch with no similar batteries in your stores I usually take the FT store recommended battery spec as my starting point, since that must work for the majority of builds otherwise they wouldn’t sell any!
 

FDS

Elite member
@RC Soarer
C rating is the max discharge rate of the pack at 1000mah. So if you have a bigger or smaller pack it will vary. As a rule of thumb-
C rating x Ah = actual max discharge.
So for your 1000mah 25c that would be 25 x 1 = 25. If you had the same rating on a 2200mah pack then it would be 25 x 2.2= 55A
To convert MAhto Ah, divide the MAh by 1000.
Generally lower discharge packs have higher internal resistance which limits their performance. Going less than 25c for most RC is not practical, since motors with props run all the time and can pull fairly high loads.
In practice real performance above 55C is rare, unless the pack is a top end racing one. Most packs that quote above that can’t really achieve it.