[F3A-Discussion] Rule proposals

Thu Sep 1 10:44:37 AKDT 2016

So to chime in here…

Yes, Amps kill… but the body has natural impedance that requires sufficient voltage to push through it.  Right now if you accidentally short a 10S pack, (and I’m guessing many of us have) we don’t feel the jolt even though over 200amps have likely passed, but rather we typically just get burned on the skin (and melt a connector).  This is because the resistance in your skin prevents the amperage from traveling through you.  50V won’t meaningfully impact that.  Yes, it’s an increase, but not a dangerous one.   It’s pretty universally accepted that 50v DC is safe at any amperage (from it being lethal) up to and including putting electrodes under the skin.  Not something I’d advise trying.

There are a number of strong upsides to this. We currently run our equipment very hard, and very hot.  Up-ing the voltage by 20% would significantly reduce both and significantly increase the efficiency and tolerance of the systems in play.   Weight would not be impacted as you would run lower capacity, higher voltage cells that would weigh roughly the same, but run cooler, last longer, and provide equal or longer flight times.

The clear downside as mentioned would be a bit of retooling for those that want to change.   Motor’s have to be wound differently, so a 12S Pletty is different from a 10S Pletty, though it’s the same motor casing and such, so it would be plug n play in the airframes.

Batteries we buy pretty steadily just like we did fuel… so I would imagine most would simply replace motors when they put together new airplanes and phase in new batteries as a result.  Charges would indeed be a brand new expense if you don’t currently have a charger that can handle 12S (many do as F3C and many others already run 12S.)

Overall I would be interested in this simply due to the current excessive wear on our equipment from the high amperage loads and heat.  Running 55amps vs 70amps reduces the strain on everything all the way down to the gauge of wire we run.

MARK ATWOOD
o.  (440) 229-2502
c.  (216) 316-2489
e.  atwoodm at paragon-inc.com<mailto:atwoodm at paragon-inc.com>

Paragon Consulting, Inc.
5900 Landerbrook Drive, Suite 205, Cleveland Ohio, 44124
www.paragon-inc.com<http://www.paragon-inc.com/>

<http://www.paragon-inc.com/>
Powering The Digital Experience

On Sep 1, 2016, at 1:47 PM, DaveL322 via F3A-Discussion <f3a-discussion at lists.f3a.us<mailto:f3a-discussion at lists.f3a.us>> wrote:

Yes.  Volts don't kill.  Amps do.

The potential for high amperage rates increases as voltage increases.  I don't recall the specifics, but the amount of amps generally transmittable at 42v is significantly less likely to cause (human) harm than 50v....and that is where the 42v limit originally came from.

I understand the technical benefits of using higher voltage power systems.  That said, if we are going to obsolete 10s lipos, motors, and chargers.....and accept the increased health risk of 50v.....why stop at 12s?  All the benefits of 12s (vs10s) would be further realized by going to 14s or 16s.

1, 3, 4, 5......all good.

Regards,

Dave

Sent from my Sprint Samsung Galaxy Note5.

-------- Original message --------
From: Derek Koopowitz via F3A-Discussion <f3a-discussion at lists.f3a.us<mailto:f3a-discussion at lists.f3a.us>>
Date: 9/1/16 1:19 PM (GMT-05:00)
To: Don Ramsey <donramsey at gmail.com<mailto:donramsey at gmail.com>>
Cc: f3a-discussion at lists.f3a.us<mailto:f3a-discussion at lists.f3a.us>
Subject: Re: [F3A-Discussion] Rule proposals

Thanks Don!

BTW, if anyone has some additional thoughts on why going to 12 cells isn't going to harm someone (voltage wise), please let me know.  I had heard (old wives tale perhaps) that moving above 50v of direct current increases the risk of death - actually I believe it is more the number of milliamps (current) that is lethal versus the voltage.

On Thu, Sep 1, 2016 at 10:08 AM, Don Ramsey <donramsey at gmail.com<mailto:donramsey at gmail.com>> wrote:
Nice job Derek.  I would hope all are approved.

Don

From: F3A-Discussion [mailto:f3a-discussion-bounces at lists.f3a.us<mailto:f3a-discussion-bounces at lists.f3a.us>] On Behalf Of Derek Koopowitz via F3A-Discussion
Sent: Thursday, September 1, 2016 11:17 AM
To: f3a-discussion at lists.f3a.us<mailto:f3a-discussion at lists.f3a.us>
Subject: [F3A-Discussion] Rule proposals

Hi everyone,

I've created 5 rule proposals that I will be submitting to CIAM to be considered for our next rules cycle.

1.  Rule clarification on rolls in the same direction
2.  Modify electric to use 12 cells instead of 10
3.  Change the number of judges from 20 to 16
4.  Allow a junior WC to fly in the next WC as a defending WC provided they are still a junior
5.  Clarify the definition of a pilot/caller as a team

See the attached.

Let me know your thoughts ASAP so that I can get these submitted.  BTW, if you'd like to see other rule changes, let me know and I can work on getting it submitted, if it makes sense.

-Derek

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