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Old 04-18-2013, 02:23 PM   #226
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Zero pm's when posting the results here for everybody to see ! I guess it was not really a big difference from charging at 40amps , since you competed charging at 40amps..... Anyway, it's good to know someone is out there pushing the envelope, and doing what we don't dare to do...... Thanks for sharing, and NO I am not pulling your chain : that's just me..... Very persistant when it comes down to knowledge, that's all !!! Hope to race you someday. See you.....

Heck I posted exactly how I was doing it at 40 amps and still got a ton of PM's wanting the exact info I posted... I'll just say there was not as much of a gain when going from 40-70 as there was when going from 20-40. The biggest reason I think is the 70 doesnt actually put as much heat into the packs as it only takes about 5 minutes to fully charge a dead (6.2V) 2S 7200mah pack. Where as at 40 it takes about 12-14 minutes depending on the end voltage drop back % on the Duo 4010. SO my opinion from my testing is there is a limit of charge rate versus time versus gains at the higher amps.

And the difference you gain at 40 amps you loose in 2-3 wrecks on the track. So unless someone can drive perfect for 5 minutes its probably not worth them spending the money and doing it.

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Old 04-18-2013, 02:58 PM   #227
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I see .... Very interesting that time became a factor, and that I presume 12 to 14 minute charging range produces the best heat/Performance in your pack... I'll definitely play with the charge rate of my TP1430C so I can get in that time range , although my packs are only 3200mah to 5300mah..... Thanks for the info !!!
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Old 04-18-2013, 03:35 PM   #228
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And the difference you gain at 40 amps you loose in 2-3 wrecks on the track. So unless someone can drive perfect for 5 minutes its probably not worth them spending the money and doing it.

EA

Define "wreck". To me, a wreck is flipping off a dot or launching off a pipe and losing 2-3 seconds. Times 3, that's 6-9 seconds, which is half a lap. Considering that anyone doing 2-3 wrecks in 5 minutes is going to have them with or without a 40 amp charge, it still sounds worth it! Or worth ruling against.

Or do you mean brushing a flapper or running wide and losing .3-.5 seconds?

-Mike
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Old 04-18-2013, 04:26 PM   #229
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Heck I posted exactly how I was doing it at 40 amps and still got a ton of PM's wanting the exact info I posted... I'll just say there was not as much of a gain when going from 40-70 as there was when going from 20-40. The biggest reason I think is the 70 doesnt actually put as much heat into the packs as it only takes about 5 minutes to fully charge a dead (6.2V) 2S 7200mah pack. Where as at 40 it takes about 12-14 minutes depending on the end voltage drop back % on the Duo 4010. SO my opinion from my testing is there is a limit of charge rate versus time versus gains at the higher amps.

And the difference you gain at 40 amps you loose in 2-3 wrecks on the track. So unless someone can drive perfect for 5 minutes its probably not worth them spending the money and doing it.

EA
I hear that alot of tracks are going to band charging over 20 amps?
Is this true??
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Old 04-18-2013, 04:27 PM   #230
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Most top racers only make One or two mistakes in a six minute run: that's where the optimal charging rate will make a difference... Flipping or losing two to three seconds are total wrecks to me. Hitting the boards alot is really what hurts my laptimes now...
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Old 04-18-2013, 08:15 PM   #231
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I hear that alot of tracks are going to band charging over 20 amps?
Is this true??
First I have heard anywhere. I now ROAR dropped their rule BUT did add that you MUST balance charge now. Should be in the updated forthcoming rule book.

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Define "wreck". To me, a wreck is flipping off a dot or launching off a pipe and losing 2-3 seconds. Times 3, that's 6-9 seconds, which is half a lap. Considering that anyone doing 2-3 wrecks in 5 minutes is going to have them with or without a 40 amp charge, it still sounds worth it! Or worth ruling against.

Or do you mean brushing a flapper or running wide and losing .3-.5 seconds?

-Mike
Brushing 2-3 flappers costing you .3-.5 a lap is what I was inferring. LOL

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Old 04-20-2013, 07:57 AM   #232
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Slightly on topic, slightly off topic...

http://www.lithipedia.org/#

Maybe they'll test some our racing type batteries.
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Old 04-20-2013, 03:13 PM   #233
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Nice read, but how many of them actually race ???
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Old 04-20-2013, 04:09 PM   #234
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Originally Posted by bertrandsv87 View Post
Nice read, but how many of them actually race ???
If they race or not does it matter...we are ones using lipos and I would like to have as much knowledge of lipo safety as possible . An aquaintance at work lost his house to a lipo fire. It was a battery he used for flying helicopters.

I guess you didn't read....The reason....or... the mission. Seems to be "safety" related more than racing. This whole thread has been very interesting and thought provoking. I am very careful with my lipo handling and charging. Now I have a new respect for lipos since viewing the lipo fires. My quality lipo sack is now retired. I purchased 2 "steel" cash boxes from Staples $15.99 ea. Question is how do you handle the charge and balance leads out of the closed metal box???????
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Old 04-20-2013, 04:12 PM   #235
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Nice read, but how many of them actually race ???
NONE!

There is NO threat at charging quality lipo cells at 5C, just benefits!
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Old 04-20-2013, 04:34 PM   #236
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Originally Posted by THEBIGBULL View Post
If they race or not does it matter...we are ones using lipos and I would like to have as much knowledge of lipo safety as possible . An aquaintance at work lost his house to a lipo fire. It was a battery he used for flying helicopters. I guess you didn't read....The reason....or... the mission. Seems to be "safety" related more than racing. This whole thread has been very interesting and thought provoking. I am very careful with my lipo handling and charging. Now I have a new respect for lipos since viewing the lipo fires. My quality lipo sack is now retired. I purchased 2 "steel" cash boxes from Staples $15.99 ea. Question is how do you handle the charge and balance leads out of the closed metal box???????
Use a file or grinder and make a U opening on the box just under the lid. Glue a piece of grommet to it to prevent the box from cutting the wires. The opening should be just enough to pass through a pair of 10AWG and 6S leads. You want to choke the Lipo if it does decides go up in flames.
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Old 04-20-2013, 08:30 PM   #237
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Thanks Team Grid. Exactly what I had in mind, just looking for confirmation. THANKS!!
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Old 04-21-2013, 07:06 AM   #238
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Sorry... not for the lipo... for the Power Supply... the HP power supply... I found a reasonable price, the question is will it fit... If it all works out, I will post the place here..
I recieved the Heat Wrap and it worked great, for a good price.

If you are interested in Heat Wrap for the HP power supply, you can find it here: The size that works is 132mm.

http://www.onlybatterypacks.com/show...emID=12753.116
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Old 04-21-2013, 04:41 PM   #239
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Great way to sell more packs....
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Old 04-22-2013, 09:45 AM   #240
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Is 20amp + charging limited only to full size packs? Or can the Shorty Lipo's be charged at the higher rates? And since shorty lipo's come in odd number mah amounts (e.g. 3800 or 4300) can you just simply "round up" when charging at 3c+? I.E. 4300 = 4.3 (1c), so 3c = 12.9amp (round up to 13amp charge rate?).
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