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Old Mar 03, 2004, 11:59 PM
won
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Massachusetts
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Just wanted to clarify hoppy's post. hoppy is correct when you're dealing with duration at a given power output. Just remember that if you switch from a 2 cell pack to a 3 cell WITHOUT changing gear ratios (to have the same power output at max throttle), the 3 cell pack will run down faster at the same throttle stick position. Of course you'll also have a lot more power.

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Old Mar 04, 2004, 12:34 AM
Nimble with Gimbals
San Diego, CA
Joined Apr 2003
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I'm sorry for your loss and I'm glad you and yours are OK. That being said, this event is more proof that autodetection chargers are safer than user-selectable ones.
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Old Mar 04, 2004, 03:16 PM
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Except for the condition where the charger mistakenly detects the wrong sized pack.
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Old Mar 04, 2004, 05:44 PM
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Walled Lake, MI, USA
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My impression from reading a whole bunch of Li-poly charging accident reports is that there really haven't been that many autodetect mistakes compared with human manual setting errors. The newer autodetect chargers in particular have some pretty sophisticated autodetect circuits. They may not be perfect, but they're darn good. Plus you can always doublecheck the autodetect to see if it made the correct choice.

Having said all that, manual chargers are still good for those who are extremely organized and focused. I think you really have to be realistic about knowing yourself before deciding which type of charger best suits your personality.
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Old Mar 04, 2004, 06:14 PM
CLUB GITMO
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Little Rock National Airport
Joined Nov 2003
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fireproof safe

Harbor freight sells a small safe...(heavy but easy to carry unless bolted down) It is fireproof and costs about $35 bucks. (about 12"X12")
Could one rig a computer power supply fan and vent the safe to charge the batts??? Drill a few holes for connections...dremel out some vents....
This may be over cautious, but just a thought.........I am sure if I thought of it, it has already been considered....
These new batts are starting to really concern me.....I think I could go by the safety rules, but how many pilots are "plug and play"????
spot
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Old Mar 04, 2004, 06:48 PM
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My problem was a tendency towards plug and play and being absent minded. I could have sworn I was using a three cell pack!!! It was really a stupid mistake made in haste, confusion and fatigue (I recovering from a headcold).

It certainly will not happen again to me!

In case anybody (else) feels like chastising me for my actions, don't bother. I got the message fully when I posted my acceptance of responsibility. Any 'piling on' of accusation, chastisement or ranting is really a reflection on the poster. This last bit is not directed at any of the last few posts, just a carry over from elsewhere on RCGroups.
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Old Mar 04, 2004, 07:05 PM
CLUB GITMO
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Little Rock National Airport
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Martimer

I in no way was chastising you.......(SIC) (I cannot type or spell)
I am glad you posted this and let people know how very important the lipolys are when charging.........I commend you for tellling your situation......This could have saved a life.
When I get a new toy...the last thing I do is read ALL the instruction.....With lipolys....I WILL know what I can...DO
Good luck...
Regards
Sunspot
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Old Mar 04, 2004, 07:20 PM
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Sunspot - you did not chastise me. As I typed, that last bit was NOT directed at the last few posters.

Sometimes reading the directions is not enough to prevent disaster - I read them and still managed to mess things up. Sometimes following the directions is not enough - I was following the directions and just had a mental breakdown. I thought I was charging a three cell pack, it was a 2 cell pack. The mistake was mine. An absence of follow through. A failure to follow procedures that I needed.

I will be writing the cell pack and jumper settings on all my packs when I resume 'playing'. I have a 'plug and play' attitude towards this hobby - not a bad thing as long as I stay within my limits (I will not fly over or in crowds for instance). If I label the packs properly for my use in my charger, there will not be another accident like this (I reserve the right to plow my helpless aircraft into whatever surface I or my twitchy fingers deem fit to plow them into!). It was that simple.

Many people make mistakes. It was a mistake that led to the problem - if people learn from my mistake then some good will have come from this. I know I sure learned some things!

I especially appreciate all the knowledge gained from this venue. Nobody thought of the pack marking idea, so obviously there is knowledge to share.

There were two people who were less than polite (and you probably do not even know who you are) and I learned once again that it is possible to be a jerk while being helpful.
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Old Mar 04, 2004, 07:35 PM
CLUB GITMO
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Little Rock National Airport
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I have met some jerks too on this site.....They have not all been fellow pilots responding to my posts. (it is normally someone that worries about something in the wrong place).....these people I don't really worry about...They have never had any authority, and I would bet they got their lunch taken away in school.
The pilot that thinks he does not need help in some form is only fooling him/herself..........I need help everyday.........Eflight is very new to me.............If glow is the issue I can scrap......:-)
spot
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Old Mar 04, 2004, 08:00 PM
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We are all glad when this kind of stuff happens without injury to a person.

Is important now to not give up. While it was an expensive lesson, no doubt, is is one that you will never forget -- or repeat.

The benefits of this new technology are immeasurable. Simply put, they make electric airplanes interesting. Try to get someone who has been flying LiPolys to go back to NiMh of NiCD.

I'll betch they won't go.

Drop back now, take deep breath and then start figuring out how to rebuild everything better than is was the first time.

You have a great story for your grandkids.

We're glad you and yours are OK.
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Old Mar 04, 2004, 10:54 PM
Space Coast USA
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martimer,
you are not alone -
http://www.rcgroups.com/forums/showt...06#post1400206
hoppy
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Old Mar 05, 2004, 02:14 PM
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Syracuse Hancock, New York, United States
Joined Oct 2002
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I have a question.
do these cells give off any fumes or anything when charging?
the reason I ask is, if not woulndt it be better to charge them in a sealed enviorment?
I like the fire safe idea, I have been using a dish with the lid on.
I just dont understand why you would need to vent the firesafe. If you are charging at a proper or lower rate, there should be no heat, and therefor no reason to vent. correct?
My thought is this. close are less O2. most fires need O2 to burn, I know a lipoly would be a chemical fire. But shouldnt this thought hold true?
thanks for any thought.
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Old Mar 05, 2004, 03:29 PM
Does anyone hear a cat?
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Tallahassee, FL
Joined Sep 2003
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Martimer -- you've got the right idea now. I actually use different plugs for my various packs and they all have color coded tape on them. Red = 3cell, Blue = 2cell. My charger leads have tape on them for the types of plugs i use on each pack. I use a triton charger and have yet to choose the wrong memory profile -- it's all about getting a routine down and following it precisely every time. I'm very glad that your home wasn't badly damaged and that you and your family are unhurt. Posting here is a good thing to do. Reports like yours can help other people in the same situation as you are keep from making the same mistakes.
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Old Mar 05, 2004, 03:40 PM
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My next fear to overcome is the fear of an out of balance or 'hard landing' damaged pack. Any 'hot tips' for how to handle that eventuality?
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Old Mar 05, 2004, 03:43 PM
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North East
Joined Nov 2001
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Gameboy

My 9 year old has one of those gameboy advances and it too has a lithium battery I noticed. He just puts in in the dock when he feels like charging it. I know these games draw very little amperage so are these things immune to fires?
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