battery question... running 2 packs in parallel?

[eckloss]

ok, maybe a dumb question, but just want to make sure before i burn something out inadvertently...

the setup is: merriman wtc 3.0, thor apc and failsafe, caswell viper 10 sub esc with 1.5a bec

batteries i want to use: piranha 1900 6-cell, 7.2v pack

question 1: is that 1900mah on the batteries going to be too much for the bec/esc to handle?

question 2: there is enough space to run 2 of these packs in parallel to extend run time and give me the little extra weight i need. any issues with doing that?

[petn7]

Re: battery question... running 2 packs in parallel?

[quote]ok, maybe a dumb question, but just want to make sure before i burn something out inadvertently...

the setup is]

I can only answer your first question, but you should be fine. Running in parallel will just double your mah capacity and allow for longer run times.

[eckloss]

i didnt even occur to

i didnt even occur to me until i was writing that post that the esc/bec is rated for 1.5a, but the batteries are 1.9a....

do i dare risk it?

[petn7]

i didnt even occur to

i didnt even occur to me until i was writing that post that the esc/bec is rated for 1.5a, but the batteries are 1.9a....

do i dare risk it?

I don't think the BEC will draw whatever current the battery is physically able to deliver. BEC amp draw is only an issue if you have a bunch of high draw servos or something.

[JWLaRue]

No, no, no....! http://www.subcommittee.com/forum/icon_smile.gif

You are

No, no, no....!

You are mixing two different terms. Amps is not the same as amp-hours.

Amperes is the measure of the amount of current.

Amp-hours tells you the amount of power that can be drawn from the battery over a specified period of time. The higher the amp-hour rating of the battery, the longer you can run under similar circumstances than with a battery with a lower amp-hour rating. Conversely, the higher your amperage (current draw), the less time to drain the battery.

Unless you are doing something to create an abnormally high amperage draw, using those standard r/c car battery packs is perfectly fine with that type of dive module...or just about any dive module.

-Jeff

p.s. running two packs in parallel, e.g. doubling your amp-hours while maintaining the same operating voltage is also good.

[petn7]

Right, a 1.5 amp rating

Right, a 1.5 amp rating is not synonymous with 1.9ah capacity battery pack.

However, a 1900mah battery pack could deliver 1.9 amps for one hour, give or take for loss.

[JWLaRue]

Yup...and even for those inexpensive

Yup...and even for those inexpensive and power hungry Graupner motors that are in a lot of dive modules, that's still a lot of run time.

-Jeff

[eckloss]

thanks guys. much appreciated!

sorry i

thanks guys. much appreciated!

sorry i missed u at the regatta this year jeff. hell, i dont think ive seen you since 1999 or so. hope all is well. ill be at at least one or two sce runs this fall.

[JWLaRue]

Hi Erich,

...yea, I missed me

Hi Erich,

...yea, I missed me at the regatta too!

It's become a fact of life for me since my customer (US Federal govt) insists on doing a lot of year-end spending this time of year. ...does keep us employed though!

We'll be starting our indoor running season in October and once again we'll be in southern PA, just a bit south of York. Definitely hope to see you there!

-Jeff

[eckloss]

ill be there in oct.

ill be there in oct. im heading to merrimans house the sat before to pick up the vanguard. also bringing my copeland la boat i snagged at the regatta for (gasp) only $230 bucks. couple more days and itll be done. just waiting on my esc to arrive b4 i trim it out and get her in the water.