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Ian_Gsi16V

EZrun 2S Cut off voltage setting

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I just want to check this before I set it on mine as I am weary of ruining any of my batteries...

Should the cut off voltage on my EZrun be set at 3.2v for 2S batteries? I had it set to 3.4v but the voltage cut off was kicking in as soon as I gave it a burst of acceleration.

I have been using it with no lipo cut off recently but just using a 3rd party alarm to alert me but I would rather use the built in function if possible.

Thanks :)

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you shouldn't be getting voltage cutout at 3.4v from a full rip on the trigger, seeing that at full charge the voltage is 4.2 volts per cell, unless your battery wasn't fully charged to start with.

set your esc to the voltage you like, adjust the alarm to the same voltage, make sure the battery is fully balance charged and reading 4.2 volts (or there abouts) in all cells, then go play, if you get power loss without the alarm sounding off then you have a power delivery problem, meaning the esc is cutting out from something else, could be over volt, over temp, signal loss by brown out to the rx, or even a dodgy wire or solder joint somewhere in the whole line from battery through esc out to the motor, and also out to the rx and onto the servo.

as for the voltage level, 3 volts per cell is the absolute minimium for a lipo battery, so a cut out set above that will be fine.

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Cheers, it happened on 3 different batteries that where all fully charged. I balance charge my batteries each charge.

I'll alter the voltage and try it again.

With the cut off disabled it all works flawlessly, I have ran a few packs through it without issue.

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What is the cut off voltage of the alarm that you are using??

Why not set the ESC to 3V/cell (the recommended minimum voltage) and then continue to use the alarm..

Stop driving when the alarm sounds, or if the alarm happens to fail, then you have the cut off in the ESC as a backup..

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What is the spec of the batteries - if they are low C rating they may not be able to fully deliver the instantaneous demand from the motor/ESC ?

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What capacity?

All 3 are 4000mah.

1 is a Brainergy and the other 2 are Turnigy.

Hopefully i'll be trying it out again this weekend weather permitting.

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Update - This weekend I set my ESC to cut out at 3.2v, although it never fully cut out if I kept the power on for a long run ( I was on the beach) it was going in to low power mode.

Clearly an issue somewhere but it all works fine with my third party alarm so it is something I plan on trying to address but luckily not a show stopper.

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Maybe its just a case of the low voltage circuit in the ESC being out of spec/calibration, which is causing the LV cut off to be overly sensitive..

Have you tried another remote alarm to ensure that it is not the remote alarm that is faulty?

If you have a digital voltmeter and a high current discharger you could test it..

Personally I would just keep using the remote LV alarm.. What I like about these remote alarms is that they connect to the balance lead, and monitor the voltage of each cell in the pack..

The LV cut off in the ESC just monitors the total pack voltage, meaning that if the cells in your battery become unbalanced, one cell could go below the cut off voltage, and you probably wouldn't find out the cell was damaged until the next time you charged the battery.. (which if it was NOT balance charged, could result in a cell failure)..

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The LV cut off in the ESC just monitors the total pack voltage, meaning that if the cells in your battery become unbalanced, one cell could go below the cut off voltage, and you probably wouldn't find out the cell was damaged until the next time you charged the battery.. (which if it was NOT balance charged, could result in a cell failure)..

I'll second this, as I experienced it recently with my Blitzer beach running. Car went in to 'recovery', so I stopped, replaced the pack. I was explaining the kit to a mate, so I popped the alarm on to show him. Cue concerned looks as one cell was high, one read 2.8. Seems to have recovered on subsequent balance charges, but I have a 3s now that will not charge :(

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Maybe its just a case of the low voltage circuit in the ESC being out of spec/calibration, which is causing the LV cut off to be overly sensitive..

Have you tried another remote alarm to ensure that it is not the remote alarm that is faulty?

If you have a digital voltmeter and a high current discharger you could test it..

Personally I would just keep using the remote LV alarm.. What I like about these remote alarms is that they connect to the balance lead, and monitor the voltage of each cell in the pack..

The LV cut off in the ESC just monitors the total pack voltage, meaning that if the cells in your battery become unbalanced, one cell could go below the cut off voltage, and you probably wouldn't find out the cell was damaged until the next time you charged the battery.. (which if it was NOT balance charged, could result in a cell failure)..

Yes, I have tried a couple of alarms, they all appear to work fine. I get about 20 -25 minutes of running my Blitzer with a 9T EZrun off a 4000mah 2S before the alarm goes off which seems about right to me. Run time varies slightly depending on the terrain where am I running it which I would expect.

I'll second this, as I experienced it recently with my Blitzer beach running. Car went in to 'recovery', so I stopped, replaced the pack. I was explaining the kit to a mate, so I popped the alarm on to show him. Que concerned looks as one sell was high, one read 2.8. Seems to have recovered on subsequent balance charges, but I have a 3s now that will not charge :(

I have wondered this myself and concluded the voltage monitors that connect to the balance lead are probably more accurate than the ESC that just monitors the overall pack voltage.

I think I will just get myself a couple more (and slightly better) voltage alarms and leave it that that :)

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