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Venom pro charger problems, help please

Venom pro charger problems, help please

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Old 03-12-2010, 02:13 PM
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Default Venom pro charger problems, help please

I just bought a new venom pro charger and im having a couple of problems. Charges nimh no problem so i must be doing it right. Im having problems charging lipo.

Problems are

1. I have 3ser batteries and the charger reads 2ser
2. When i choose 2ser charges for 25 seconds and stops because it is full but obviously is not
3. Plug it some other lipos and say voltage too low or something

So can anyone help me please, i read that the dean plugs that come with it aren't good, but want to see if anything else could be the problem so.
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Old 03-12-2010, 02:19 PM
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You want to set the charger on lipo balance charge mode. Plug the balance plug into the charger, and the main "deans" plug in. Set your charge rate, and set it to 11.1V. When you hold the start button it should say something like 3s--3s confirming you have selected 3s and it is reading 3s. If it is not reading 3s then you battery voltage is too low. Maybe your packs have been sitting too long? Maybethey are damaged?
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Old 03-12-2010, 04:16 PM
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No if the deans plug that comes with it is bad, it won't connect. Thats not what your prob is.


If your 3S lipo doesn't have at least 9volts, the charger is going to think its a 2S. Can you check the voltage on the 3S with a voltmeter?
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Old 03-12-2010, 11:45 PM
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Originally Posted by Duster_360 View Post
No if the deans plug that comes with it is bad, it won't connect. Thats not what your prob is.


If your 3S lipo doesn't have at least 9volts, the charger is going to think its a 2S. Can you check the voltage on the 3S with a voltmeter?
Well i try charging it under 2s with my 3s and it doesn't charge at all and says it is 8. something v everytime. I dont think my lipos are broken, 1 i got recently and the other is i bought used but i dont think its broken.

What would happen if i just press start when the charger reads 2s but i say its 3s?
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Old 03-13-2010, 09:58 AM
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You won't get anywhere if the lipo voltage is not above the minimum of 3 volts per cell. The chargers builtin safety feature won't let it charge a lipo that has less than 3volts per cell. So if your 2S has less than 6v,it won't chanrge, if the 3S has less than 9volts, it won't charge.

It doesn't matter how new or how old lipo is, if its been overdischarged below 3v/cell, the charger is not going to charge it.
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Old 03-13-2010, 10:26 AM
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Originally Posted by Duster_360 View Post
You won't get anywhere if the lipo voltage is not above the minimum of 3 volts per cell. The chargers builtin safety feature won't let it charge a lipo that has less than 3volts per cell. So if your 2S has less than 6v,it won't chanrge, if the 3S has less than 9volts, it won't charge.

It doesn't matter how new or how old lipo is, if its been overdischarged below 3v/cell, the charger is not going to charge it.
So what do i do then. I didn't discharge it, i just used it until i didn't get a response out of it.
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Old 03-13-2010, 01:53 PM
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I'm a little concerned about going further cause reading your posts worries me you don't understand much about lipo and how they work.

Read this and follow instructions carefully. You're going to try charging the lipo as a NiMh, but only just long enough to get voltage back over 9v!! If you leave the lipo charging as a NiMh it will damage it and likely vent and potentially catch fire!! You'll need to tell charger its a 7 or 8 cell pac and that should allow it to charge - charge at 0.1 - 0.2amps and nothing higher. You want a low charge rate so the voltage doesn't go up too fast and damage the lipo. As soon as you see the voltage up over 9 volts STOP the charge! Don't not leave while any of this is going on, stay with it and carefully monitor the charger and voltage on the lipo.

Now switch to a lipo charge and it should charger normally. If you see the lipo begin to swell at any time, stop, disconnect everything and take it outside and leave it for at least a day. Its become potentially unsafe. If it doesn't get any bigger, you can try resuming and I would be doing this outside so if anything happens, it doesn't ruin anything.

This is the typical rescue for an undamaged lipo thats been slightly overdischarged. Its worked countless times for many people but you have to know what you're doing. If any of this makes you uncomfortable, please get some help someone with more experience.
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Old 03-13-2010, 02:11 PM
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Thanks it worked, but i had to do it like 5 times, i start charging it and it starts decreasing then i turn off then start again, is there a reason why it decreses after i start charging?
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Old 03-13-2010, 03:40 PM
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I'm sorry, but I have no clue what you're trying to say.

What starts decreasing?? Voltage? Are you talking about lipo mode charging or are you still trying to charge as a NiMh??
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Old 03-13-2010, 07:17 PM
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nvm i got it, thanks for the help
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Old 03-13-2010, 08:13 PM
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Originally Posted by TrooShot View Post
..... I didn't discharge it, i just used it until i didn't get a response out of it.
When you run your RC, you are discharging the battery. That is how you overdischarged it and unless you're using a low voltage cutoff like you should be, you'll overdischarge it again. You don't run lipo "until I didn't get a response out of it". You only do that with NiMh and NiCds and thats not really the best way to treat them.

Each time you overdischarge a lipo you are damaging it. Do it enough, the lipo will swell up and its done. Keep using it while its puffed and you chance burning your RC up when the lipo vents and lets go.

Good luck!
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Old 03-25-2010, 11:07 AM
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Dont want to threadjack or anything but im having problems with my venom charger as well, yesterday i bought 2 stickpack nimh 4500ma for my starter box and a stick pack reciever battery nimh thats 1600, when i threw them on the charger it only put about 200ma ino each battery. When i put them in my starter box it only took about 20 seconds to run them down dead and the same with my reciver battery, it only ran my buggy about 3 or 4 minutes before it prety much died, when i tried to charge them again the charger would only put about 1000 at a time into each big stick pack before it said fully charged, i had to keep starting it over, the reciver was the same, but it would only put about 200ma each time i hit charge, ive been having this charger for over 6 months now and this is the first time its done this, any ideas on what could be wrong, if its just the charger, wire connectors or batterys thats the problem?
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Old 03-25-2010, 11:24 AM
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Sounds like bad case of false peaking - NiMhs can do that - you just reset the charger and charge again. New batts seem to do this more than older ones so that might be why you haven't had the prob before.

What do you have the peak sensitivity set at? If iits real low, you minght try setting it a little higher. ALso if you're charging near the max charge rate for the charger, that also may make it worse.
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Old 03-25-2010, 12:19 PM
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Originally Posted by Duster_360 View Post
Sounds like bad case of false peaking - NiMhs can do that - you just reset the charger and charge again. New batts seem to do this more than older ones so that might be why you haven't had the prob before.

What do you have the peak sensitivity set at? If iits real low, you minght try setting it a little higher. ALso if you're charging near the max charge rate for the charger, that also may make it worse.
Well that makes sense, the 4500s i was charging at 5a which is the max of the charger, and i tried the recever pack again today and it took a full charge nonstop finally after the second discharge. And setting the peak sensitivity i really dont know how, havent tried and i dont know what its set at, i'll have to find out where that is and give it a try changing it alittle. What kept confusing me was that after i charged the batteries they were still showing just alittle over 7.4 volts so i figured they were charged, then again, im not super sharp when it comes to electronics, just thought at first it might have been the series connector i made, thought it might have been a bad connection or something. I know just enough to get by, lipos are like my worst enemy, i actually changed my mind on getting a lipo starter box battery because of not having a low voltage shut off and how much trouble i have with lipos (IE. had two losi 4s lipos and put a half charge on them and stored for 2 weeks and when i went to charge them to use them the voltage was too low to charge them properly, i had to boost them alittle with nimh charge)
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Old 03-25-2010, 12:26 PM
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Another question is would a 3s 2200 lipo be enough to run a starter box for a few cranks, i have two kinda cheap hongkong batteries that i havent done anything with, im wondering if i could just wire them up as two backup packs incase my current ones die off, and im prety sure i cant just wire them up in series, im sure a 6s battery would be too much.
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