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Old 08-16-2011, 12:37 AM   #5881
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Originally Posted by SpeedFreakNL View Post
On the FW518 I used before I did not have the problem and the cut-off kicked in right.

I removed the battery form the car, pluged it in the charger (Graupner Ultramat 16) and before charging I did measure the voltage of the cells.
Than charged it quickly and within a few seconds it was above the 3.2Volt/Cell

So luckily the battery survived
*The following description is for your own risk*

If your charger does not want to charge your lipo anymore, because of low voltage, there is a very easy way to get it above 3V/cell again.
Put your charger in NiMh mode, and charge the battery, with the lowest current setting possible, 0.1A if possible. Charge your Lipo on this setting, for a brief moment, and watch the voltage of your pack during charging. When it gets above 3V (per cell), stop charging, switch the charger to Lipo mode and start your normal Lipo charge program.

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I set mine at 3.2Volt/Cell. So when the 2 cell pack drops below 6.4 Volt for more than 2 seconds the Cut-off should kick in right?
Yes, but only if you set it at the preprogrammed settings. If you choose the "custom" setting, and want a cutoff of 3.2V/cell, you need to set it at 6.4V
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Old 08-16-2011, 01:20 AM   #5882
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Originally Posted by M7H View Post
*The following description is for your own risk*
If your charger does not want to charge your lipo anymore, because of low voltage, there is a very easy way to get it above 3V/cell again.
Put your charger in NiMh mode, and charge the battery, with the lowest current setting possible, 0.1A if possible. Charge your Lipo on this setting, for a brief moment, and watch the voltage of your pack during charging. When it gets above 3V (per cell), stop charging, switch the charger to Lipo mode and start your normal Lipo charge program.
I've done this myself as well, it does work to bring a pack back if the charger doesn't want to accept it. However, just need to remember to switch back to lipo mode as soon as the voltage is right!
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Old 08-16-2011, 02:19 AM   #5883
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The safest way to bring back lipos to above the cut off voltage is to do the following

2s lipo charge with 1s setting with no balance lead for a max 10 minutes

3s lipo charge with 2s setting with no balance lead for max 10 minutes.

4s lipo charge with 3s setting with no balance lead for max 10 minutes

and so on

then use the proper function to full charge the packs .

I dont recommend nimh setting .
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Old 08-16-2011, 03:39 AM   #5884
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A 2S lipo, of 2.5V/cell, will give an over voltage error on a 1S charge setting.....

A completely dead Lipo, will have a huge internal resistance, and will even on a low current of 0.1A quickly rise above 4.2V/cell, I've even seen 6V!...
But because it was dead already, it will not explode, or what so ever, because there is no juice left in it anymore to give such a reaction!....
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Old 08-16-2011, 03:52 AM   #5885
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i had a customer who discharged his 7.4V pack waaaay too low (4.48V), under 1S it registered as too high voltage and at 2S, it registered as too low voltage.

Yup, go into any other non-lithium battry profile, bring up the voltage back to 6V and you're good to go. No myths. Just do it, no ill effects assured.
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Old 08-16-2011, 04:17 AM   #5886
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Quote:
Originally Posted by M7H View Post
A 2S lipo, of 2.5V/cell, will give an over voltage error on a 1S charge setting.....

A completely dead Lipo, will have a huge internal resistance, and will even on a low current of 0.1A quickly rise above 4.2V/cell, I've even seen 6V!...
But because it was dead already, it will not explode, or what so ever, because there is no juice left in it anymore to give such a reaction!....
i am just giving you information from my long testing a good charger will work that way as i mentioned .
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Old 08-16-2011, 06:14 AM   #5887
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Yes, but only if you set it at the preprogrammed settings. If you choose the "custom" setting, and want a cutoff of 3.2V/cell, you need to set it at 6.4V
Yes, is wat al sugestud setting and not a custom setting.
Thanks.
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Old 08-16-2011, 06:21 AM   #5888
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Made a stupid mistake before where I forgot to plug off the battery connector from the battery. I am one of the guys who like to connect my cooling fan directly to the wire that leads to the battery. It was left on for 2 days before I realised it. Battery went bloated and could not be charged using normal function. Again what I did, I charged it using NiMH function for a few minutes before charged it again using Lipo function. Battery was ok until now. The real stupid thing was the battery was only a couple of weeks new.

Nowadays, I checked the car twice to make sure I really did plug the battery connector off the battery.
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Old 08-16-2011, 07:18 AM   #5889
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Hi,
I am trying to change my esc from stock to mod.....but nothing happens?...green esc lights up in the box on the screen to say its connected?

also what mod firmware should i go for?.....its for a electric motorbike,using a speed passion 6.5T motor,want smooth power delivery.....

thanks simon
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Old 08-16-2011, 11:48 PM   #5890
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Hi,
managed to get firmware changed,but went for V1 508 no timing...is this any good?..like i say just want very soft/smooth power delivery.....
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Old 08-17-2011, 12:54 AM   #5891
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Quote:
Originally Posted by rai View Post
Made a stupid mistake before where I forgot to plug off the battery connector from the battery. I am one of the guys who like to connect my cooling fan directly to the wire that leads to the battery. It was left on for 2 days before I realised it. Battery went bloated and could not be charged using normal function. Again what I did, I charged it using NiMH function for a few minutes before charged it again using Lipo function. Battery was ok until now. The real stupid thing was the battery was only a couple of weeks new.

Nowadays, I checked the car twice to make sure I really did plug the battery connector off the battery.
The best thing to do is never leave a battery in your car, I always stock my battery packs in a proper paddded suitcase
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Old 08-17-2011, 01:28 AM   #5892
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Awhile ago now I reverse plugged a battery to my XERUN 120A v2 and tried to send it in for repair just to have have it return to sender. I now have a second 120A v2.1 speedy that keeps losing calibration. I would like to try and send both of these in for service/repair, what is my best option?

Thanks,
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Old 08-17-2011, 04:46 AM   #5893
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whats the difference between the v2.0 and v2.1
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Old 08-17-2011, 06:22 AM   #5894
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Quote:
Originally Posted by olly986 View Post
The best thing to do is never leave a battery in your car, I always stock my battery packs in a proper paddded suitcase
Yeah it was a lesson well learnt. Guess at that time I was in a rush and was tired after setting the car up in the middle of the night..Dont want to repeat mistake twice...hehehe
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Old 08-17-2011, 08:30 AM   #5895
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Right,gone to the 528 mod software for my bike..........can anybody give me a clue as to the softest settings???...

simon
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