Newbie to FE with battery .

[klloyd67]

I'm building a 1/10 scale FE and want to be NAMBA compliant if I decide to race. My question pertains to this battery limit description

E. POWER AND DRIVE TRAIN
E.1 Power and Drive Train rules for the vintage class are:
E.1.1 The only power source shall be up to 12 sub‐c battery cells of NiCd or NiMH chemistry, or up to 4S configured Lithium Polymer (LiPo) battery(s). The total capacity of batteries in the allowed chemistries and configurations shall not exceed a total capacity rating of 6,000 mAH and a total fully charged voltage of 16.8 volts DC.
E.1.1.a Only LiPo batteries with a manufacturer’s maximum discharge rate of 20C or greater shall be allowed for manufacturer’s rated capacities less than 4,000 mAH and a manufacturer’s maximum discharge rate of 15C or greater shall be allowed for manufacturer’s rated capacities of 4,000 mAH and up.

Does this mean I could run 2ea 2S 3000mah batteries?

Thanks, Kevin

[srislash]

How I read that is a total of 4s and 6000mah. If it were 4s2p 3000mah (2-4s packs) that adds up to 6000mah on board. One could wire 2-2s packs in series to make 4s and if they were 3000mah or less you could double them up. Or if you had 2-2s 5000mah packs in series that would work to tho. It is just just a 6000mah maximum.

[Speed3]

It appear in my opinion that if your capacity is 6000 mah you have to use 20c cells. That could be that you use 2, 2s 6000mah 20c packs and wire them in series.

I think the idea is to keep racers with cells that works out to 120 amps constant for the lipos. That is c rate multiplied by capacity in amp hours. (Example 20c* 6amp hours is 120amps constant)

And 6 amp hours is the same as 6000mah.

Then the other part is, if you want a higher c rating total capacity has to be less than 4000mah.

Those rules will keep things interesting.

[klloyd67]

[QUOTE=Speed3;730719]It appear in my opinion that if your capacity is 6000 mah you have to use 20c cells. That could be that you use 2, 2s 6000mah 20c packs and wire them in series.

I think the idea is to keep racers with cells that works out to 120 amps constant for the lipos. That is c rate multiplied by capacity in amp hours. (Example 20c* 6amp hours is 120amps constant)

And 6 amp hours is the same as 6000mah.

Then the other part is, if you want a higher c rating total capacity has to be less than 4000mah.

Those rules will keep things interesting.[/QUOTE

With a 1600kv motor and 150A ESC will I get good amount of run time?

[Speed3]

A 1600 kV with a 45mm 2 blade prop should get you over 3 minutes at full throttle in a circuit race on 6000 mah cells. With a 42mm 2 blade prop over 4 minutes in the same type of race. That's an excellent choice in kV for that class. I think the 45mm prop would be the better choice.

[Terrynewtorcboats]

I’m new to rc boats and unfortunately don’t have a clue what you’re saying. Is there anyway to maybe post a picture of what you are saying? I’ve purchased a Zelos to use after I’m comfortable with the first boat I’ve purchased and would really want to Learn all that I can. Any help appreciated. Thank you

[T.S.Davis]

Not sure where that excerpt is from but it's not part of the NAMBA rules.

Rules that rely on labels are difficult to enforce. We/us/FE have made this mistake repeatedly. Anything that can't be tech'd shouldn't be a rule.

6000 mah is almost impossible to verify at the pond on race day. I'm not sure where you would find a 15c pack these days.

[T.S.Davis]

The NAMBA rule book allows 4s up to 10000mah. How you get there is up to you. You could series 2s packs or parallel 4s packs or just buy one big 4s pack. In my kids boat we ran a pair of 2s6500's in series to make 4s6500mah. Always had fuel left but the boat liked the weight as it was super light light. We've seen scales run on as little 4400mah. Depends on the boat.

Again, nobody is checking the 10,000 mah limit as they don't have the ability. Totally on the honor system. It's not an issue in scale as nobody needs 10k for a race.

[longballlumber]

Those rules are from E-RCU. They look to be a morphed version of NAMBA or what NAMBA had at one point in time...

https://docs.wixstatic.com/ugd/485efb_7af91dd0245f419aa3e535c64609fb7b.pdf