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Thread: 11.1v lipo cutoff

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Old 04-17-2010, 09:11 AM   #1
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Default 11.1v lipo cutoff

whats the safe lipo cutoff for my thunderpower 11.1v 3s lipo?
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Old 04-17-2010, 09:17 AM   #2
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whats the safe lipo cutoff for my thunderpower 11.1v 3s lipo?

In a crawler, 3.0 volts per cell. 9.0 volts totall (3s).

In a high draw application ie. monster trucks, 3.1-3.3 volts per cell. 9.3-9.9 volts totall.
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Old 04-17-2010, 09:20 AM   #3
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ok cool, thanks bro
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Old 04-17-2010, 12:11 PM   #4
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In a crawler, 3.0 volts per cell. 9.0 volts totall (3s).

In a high draw application ie. monster trucks, 3.1-3.3 volts per cell. 9.3-9.9 volts totall.
I would think it was other way around. Voltage drops under load and goes back to resting voltage again when you remove the load. The more amps you pull the lower the voltage drops. Setting the alarm voltage too 3 volts in a low amp setup would trigger the alarm later than in a setup pulling higher amps - causing the battery to be more drained in the low amp setup. Or... did I miss something?

Last edited by Lorents; 04-17-2010 at 12:13 PM.
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Old 04-17-2010, 12:17 PM   #5
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I would think it was other way around. Voltage drops under load and goes back to resting voltage again when you remove the load. The more amps you pull the lower the voltage drops. Setting the alarm voltage too 3 volts in a low amp setup would trigger the alarm later than in a setup pulling higher amps - causing the battery to be more drained in the low amp setup. Or... did I miss something?

You have the right idea.

But, re-read my post again closely...

A crawler doesn't draw much at all so you can get away with a Lower voltage cutoff cause it won't spike below as much because it doesn't draw much to begin with. So to be safe in a high draw application you want a little higher voltage cutoff cause a high draw truck will spike way lower if you floor it when the pack is really low.

Last edited by Blood_Clod; 04-17-2010 at 12:22 PM.
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Old 04-17-2010, 12:25 PM   #6
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Read it closely again, and you suggest to set the lipo cutoff at a low voltage for a low draw setup and at a high voltage for a high draw setup - right? I am not 100% sure, but think its the other way around
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Old 04-17-2010, 12:37 PM   #7
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Read it closely again, and you suggest to set the lipo cutoff at a low voltage for a low draw setup and at a high voltage for a high draw setup - right? I am not 100% sure, but think its the other way around

Yes, your (i'm) right. But no, it's not the other way around.

Lipos are not suppose to go below 3.0 volts per cell.

For ex. I you have a E-Revo and your lipo is just about dead at say 3.3 volts per cell. And you floor the throttle that (high draw) truck will spike a large burst of power. And if you have the voltage cutoff set at 3.0 (per cell) it will spike below 3.0 (not always). Thats what we dont want to happen so to combat this we set the lipo cutoff higher at 3.2 volts so it give the battery a "voltage cushion" per say.

I don't know how much clearer i can make this. Hope this makes since... It should "Click" here soon... ha

Last edited by Blood_Clod; 04-17-2010 at 12:46 PM.
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Old 04-17-2010, 12:56 PM   #8
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I get it

My idea is that the resting voltage of a lipo should never go below 3.3 volts. Voltage under load can go below that as long as the resting voltage goes back to 3.3 or more. Setting the cutoff voltage to 3 volts in a low amp setup would drain the lipo closer to 3.3 than it would in a high amp setup.
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Old 04-17-2010, 01:01 PM   #9
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I get it

My idea is that the resting voltage of a lipo should never go below 3.3 volts. Voltage under load can go below that as long as the resting voltage goes back to 3.3 or more. Setting the cutoff voltage to 3 volts in a low amp setup would drain the lipo closer to 3.3 than it would in a high amp setup.

You got it
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Old 04-17-2010, 01:24 PM   #10
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Good info guys! I was never really sure about this so I'm glad it was brought up. Thanks!
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Old 04-17-2010, 01:38 PM   #11
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Personally I think 3V is a bit low If you want to do it the safe way you can start out with a conservative 3.2V and check the resting voltage after you are finished running it. If you want to be nice to your lipos you should aim for a resting voltage that is about 3.7 volts per cell
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Old 04-17-2010, 01:49 PM   #12
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Personally I think 3V is a bit low If you want to do it the safe way you can start out with a conservative 3.2V and check the resting voltage after you are finished running it. If you want to be nice to your lipos you should aim for a resting voltage that is about 3.7 volts per cell

Kinda... I run all my stuff (slash, crawlers) at 3.0 volts and I've never had a pack under 3.4 volts/cell when i plug it into my charger. But thats not to say it didnt' spike to 3.0v per cell. My average voltage (2s) when i plug them in is like 6.9-7.4. But, your right it doesn't hurt to be safe for how much we spend on this crap!

FYI, All castle speedos from the factory are set at 3.0v/cell.
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