New warning insert in MMM box: "DO THE MATH!"

[Pdelcast]

Believe me, there are a lot of people trying to run 15C 3200mah packs... /sigh

[BrianG]

Originally Posted by JThiessen

I havent been into the calculators in a while, so is there a way to have it also calculate maximum amp draw based on motor and gearing? It might already be there....just havent looked.

No such thing yet. Even with specifying gearing and such, there are simply too many variables to consider to be anywhere near accurate. The best you can do is estimate average current draw by your runtime and battery capacity figures, and then estimate burst current by multiplying the average current by 6-8.

Originally Posted by Pdelcast

Believe me, there are a lot of people trying to run 15C 3200mah packs... /sigh

On the next version of your ESCs, incorporate a mechanical fist that comes out and punches the user if they try to use such packs.

[pinkpanda3310]

Originally Posted by BrianG

No such thing yet. Even with specifying gearing and such, there are simply too many variables to consider to be anywhere near accurate. The best you can do is estimate average current draw by your runtime and battery capacity figures, and then estimate burst current by multiplying the average current by 6-8.



On the next version of your ESCs, incorporate a mechanical fist that comes out and punches the user if they try to use such packs.

Is that why you haven't included this on your calc sheets?http://www.rc-monster.com/forum/show...motor+amp+draw

[JThiessen]

Originally Posted by BrianG

No such thing yet. Even with specifying gearing and such, there are simply too many variables to consider to be anywhere near accurate. The best you can do is estimate average current draw by your runtime and battery capacity figures, and then estimate burst current by multiplying the average current by 6-8.



On the next version of your ESCs, incorporate a mechanical fist that comes out and punches the user if they try to use such packs.

Just figures.....sometimes looking at all these electrical numbers gives that feeling of doom I had 20 years ago in my EE and EEET classes in college. If it weren't for HP calculators, I would never had made it through those classes.

[BrianG]

Originally Posted by pinkpanda3310

Is that why you haven't included this on your calc sheets?http://www.rc-monster.com/forum/show...motor+amp+draw

Well, there are a couple reasons I didn't add that (yet):

- I forgot about it
- No feedback.

Originally Posted by JThiessen

Just figures.....sometimes looking at all these electrical numbers gives that feeling of doom I had 20 years ago in my EE and EEET classes in college. If it weren't for HP calculators, I would never had made it through those classes.

I still have my trusty old HP48gx, with a whopping 512k RAM card. lol.

[whitrzac]

Originally Posted by What's_nitro?

It's like Briggs & Stratton using "gross torque" on their engines instead of HP because THEY think it is a better way to rate the engine...... No other company uses that method... So it makes it much harder for consumers to compare different brands.

no, they do it to hide the fact that they can't make power...

[RBMike]

People need to start thinking about the power systems as just that "SYSTEMS". The ESC, Motor ,Battery & gearing are the system. The components of the SYSTEM are individual peices that need to be suitable for use with each other.

You would not go down to tire rack & get a set of subcompact car tires and expect them to work on a Boeing 747-400. Yes I know the 747 uses tires, but not ones ment for a corrola.

So yes, we all need to do the math.

Originally Posted by BrianG

I still have my trusty old HP48gx, with a whopping 512k RAM card. lol.

LOL, I still have my HP38G calc. I recently took a chem class after 10 years of graduating college (now applying to med school). It was great, when I took a test, the calc checkers had no idea to look for stored notes in my HP. They were like whatever and gave it back to me. That calc had a great solver function. Sorry OT

[BL_RV0]

Originally Posted by BrianG

On the next version of your ESCs, incorporate a mechanical fist that comes out and punches the user if they try to use such packs.

Naaahhh. Just make a version with HUGE caps so that you get a giant spark...

Originally Posted by BrianG

On the next version of your ESCs, incorporate a mechanical fist that comes out and punches the user if they try to use such packs.

while maintaining the current dimensions

[jhautz]

Seems if you want to spec a minimum capable battery for an esc, there should be some standard to defining a batteries performance. Anyone can write anything they want on the side of a lipo and have people buy it these days. Sure makes it hard for the consumers to wade thru the muck when the ESC manufacturers are saying minimum rating of a battery needs to be one thing, except for some brands that arent good no matter how they are rated, and the leading lipo pack builder has stopped using those rating standards all together.


Wait a minute.... What did I just say?


I don't get it anymore. I liked the days of figure it out yourself, burn a few things up and eventually you learn what actually works.

[hemiblas]

Theres still too many problems with the way manufactures rate lipos. 3200mah 15C batteries should be good for 48 amps continuous. To me, That means you should be able to pull 48 amps continuously during the run, sometimes more, sometimes less but an average of 48 amps. Thats a lot of amps and I can guarantee that most runs wont even come close. Even though I agree that they wont work, the math says it does and I think its the lipo manufactures are the ones at fault for improperly rating their lipos. I have learned , not thru math but trial and error, to always buy more battery than I need, but I still dont understand why we have to. It wasnt until I bought a wattmeter that I finally understood that 15C really means 5C to most manufactures.