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Old 02-18-2008, 08:48 AM   #76
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Originally Posted by hobbipro View Post
10-12c is easy to do, take that silly little electronic monitoring device out of the equation, and plug directly into 12v source! j.k. please dont try this PPl.
I've done it with 4s A123 cells (plug them right into a 12V car battery) with a length of wire that does act as a current limiter of sorts. Still... it's not 10c but it can be close when first plugged in. As hobbipro said don't try this at home kids, esp with lipos.
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Old 02-18-2008, 10:45 AM   #77
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Originally Posted by JimmyMac View Post
Hey Danny, can any discharge device be used to discharge at 35amps with 6v cutoff? Or only the GFX lipo version? I ask this because a friend tried to discharge one of the Orion lipos a few months back. I think it was either 30-35amps on a GFX. But the leads got hot very quickly! So he cut it off real quick. Just curious.


The GFX is the best discharger/charger. I will measure the temp of the leads when a pack is on discharge to see what they are at. It's normal for the leads to get warm at 30/35 amps.

I'm sure if you were to use another device at 30/35 amps you would get the same temp in the leads.
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Old 02-18-2008, 12:34 PM   #78
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I just measured wire temperatures after a 35 amp cycle and I'm getting 105-110 farenheit. If your wires got hotter than this then I suspect a bad connection which would increase resistance and create more heat.
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Old 02-18-2008, 01:37 PM   #79
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okay i have a xray 007. the biggest lipo i can use is max amps 6000. i used this all year with a 3.5 brushless. i want a hard pack and it sounds like your 4000 pack will fit. will the 3.5 have to much amp draw for the 4000. i only run one pack all year with just re-peaking it all year. will i get the same performance from your pack as the max amp 6000. is the c rating derived from the capacity. if so won't the 6000 have a higher c rating. or be able to handle a bigger amp draw.
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Old 02-18-2008, 01:44 PM   #80
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The maximum continous amp draw of our 4000 is 112 amps so your 3.5 will never come close. Your 6000 pack is 120 amps continous. I'm sure you will be happy with the performance of our pack as it has very low IR and high average voltage.
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Old 02-18-2008, 02:05 PM   #81
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i have a check point charger and a ice both the same. it will only charge at 1c. so if i buy your 4000 pack and tell the charger that it is a 10,000 pack i think it will charge at 10 amps and that is its max. do you see a problem with this.
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Old 02-18-2008, 02:10 PM   #82
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Do these packs use the PolyQuest/Thunderpower balancing plugs? If not which plugs do you need for a balancer?
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Old 02-18-2008, 02:25 PM   #83
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Originally Posted by xraysteve View Post
i have a check point charger and a ice both the same. it will only charge at 1c. so if i buy your 4000 pack and tell the charger that it is a 10,000 pack i think it will charge at 10 amps and that is its max. do you see a problem with this.
Since your running mod I don't think speed is all that important to you as you should have more than enough speed with a 3.5 so charging at higher amp rate shouldn't be required. If you do want to try it then putting your charger at 10 000 should work.

If you want even more power try discharging your pack down to 6 volts with 35 amps or possibly more to get it hot then immediately charge as this will drop the IR and increase the voltage.
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Old 02-18-2008, 02:30 PM   #84
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Originally Posted by or8ital View Post
Do these packs use the PolyQuest/Thunderpower balancing plugs? If not which plugs do you need for a balancer?
Our balance connector is the same as the E-Flite packs and the Great Planes ElectriFly packs.

If you already own a balancer with TP connectors you can get an adapter from Common Sense RC

http://www.commonsenserc.com/advance...2tp+v2&x=0&y=0
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Old 02-18-2008, 03:06 PM   #85
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Originally Posted by Danny/SMC View Post
Since your running mod I don't think speed is all that important to you as you should have more than enough speed with a 3.5 so charging at higher amp rate shouldn't be required. If you do want to try it then putting your charger at 10 000 should work.

If you want even more power try discharging your pack down to 6 volts with 35 amps or possibly more to get it hot then immediately charge as this will drop the IR and increase the voltage.
If you do tell the ice.cp charger its a 10,000 ma pack, be sure to set the max charge capacity to 40%. That way you can charge at 10 amps, but it wont ever put more than 4000 mah into the pack. I charge my orions at 2C using this method and it has worked for the last year or so with no issues.
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Old 02-18-2008, 03:27 PM   #86
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If the ICE is CC/CV charger for Lipos then there should be no need to set the maximum mAh as the charger should stop charging at 10 amps when it reaches 8.40 volts and then switch into constant voltage mode to top off the pack.

I don't want this to be taken the wrong way but some of you guys are buying expensive batteries and when it comes to chargers your buying chargers that cost less than your packs. If your serious about racing and maintaining your packs I would consider getting a CE Lipo GFX. This way you can charge/discharge and cycle your packs.
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Old 02-18-2008, 04:26 PM   #87
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The ICE is fine.

Just because it's good value for money and maybe cheaper than a lipo that could be over priced does not tell you if a charger is good or not .

The charger is limited to 1c charge rate if you set the correct mah setting. This is for saftey as many lipo's can not handle more than 1c safely and it also limits over charging total capacity. You can fool the charger by setting it higher but it is then a good idea to change the max charge % as Andrew said.

So to charge a 4000mah pack set the charge to 8000mah but limit max charge to 50%.

Danny you seem new to lipo's.

The IR is relative to the temperature of the cell. Charging at higher C rate will be of very little help if the pack is warmed externaly. There are battery pack warming devices available. My Advice is charge as slow as possible and warm packs 5 min before you race.

Do not use a lipo in cold weather without pre warming them, it creates high resistance and extra stress.

I have read that around 40 degree celcius can be optimum temps for some types of cells but you would have trouble maintaining these temps during a run as the pack will cool down. It's best to start a race around 30 degree celcius so that pack performance is level throughout the run. Depends what amp draw you use and internal resistance of the cells.

Although the ICE is a fine charge it does not balance charge or monitor each cell, you should recommend that an external balancing/cell protection device in conjuction with it.

There are now plenty of chargers on the market with balancing/tap monitoring built in, I would recommend one of those if I were you. The CE Turbo 35 GFX does not have this functionality.

Hope that help
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Last edited by JevUK; 02-18-2008 at 04:40 PM.
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Old 02-18-2008, 04:58 PM   #88
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True, while I don't have or use the ice. The ICE is a 10 Amps Max charger with 1C Max capability when it comes to charging Lipo's. So in order to charge say a 5000 Mah Lipo pack at 2C rate, you would set it to 10,000 Mah 1C Charge rate, at 50% Mah setting. The charger would eventually see the cc/cv rate safely with no issues, as it approaches the 50% Mah limit anyways.

Also what was said about temperature of the Lipo pack relative to IR and capabilities in terms of performance is also true, and plays a much larger role to achieve maximum performance, rather than putting a Lipo pack through higher charge rate or discharge rate.

I would say though the temp part aside, in addition to get best performance of the Lipo pack, the chemicals inside the Lipo's do need to be re-activated when you get to the track. This is either done by running the cars during few practice session, or putting it through a high rate of discharge (not necessarily a full blown out one) as a partial one would do a job to re-activate the chemicals inside. Then you can manipulate the pack temp as you said through other methods suggested, i.e. warmer.
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Old 02-18-2008, 05:16 PM   #89
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Quote:
Originally Posted by 4wd Racer View Post
True, while I don't have or use the ice. The ICE is a 10 Amps Max.
Ice is 8 amp max , Checkpoint is almost exactly the same charger with 10 max.

Also checkpoint has 20amp discharge whereas ice has 10amp

Oh yes and both chargers can display a discharge graph on their internal display.

yeah.. what a heap of junk they are

I have noticed that the first use of the day the lipo does need a bit of "waking
up". Like 4wd says it's best to practice with it or give it a bit of extra heat.
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Last edited by JevUK; 02-19-2008 at 11:01 AM.
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Old 02-18-2008, 07:52 PM   #90
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had me cracking up, LOL,
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