lipo protection
- Thread starter animau
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BerndM
Member
I use a device which is unfortunately no longer available called a HRPOLY-X. It simply connects in series between my 2 Deans connectors on the quad and on the battery.
I have it set for 10.5V for my 3S batteries. There is a bright LED AND a loud AUDIO alarm that starts to beep at 10.9V and the beeping speeds up as it approaches 10.5V, at which point the tone and the LED are on solid. I use the HRPOLY-X as a backup for the VU sensor and two are synched up nicely.
Once the alarm starts to beep at 10.9V, I can fly about 2 more minutes before the alarm goes solid and even then I can continue to fly for another minute or so before the quad wants to land.
If I land right at the point the alarms go solid, my 3S-2200 lipos will take a 1700ma charge which is 77% of the pack's capacity. PERFECT!!
I have it set for 10.5V for my 3S batteries. There is a bright LED AND a loud AUDIO alarm that starts to beep at 10.9V and the beeping speeds up as it approaches 10.5V, at which point the tone and the LED are on solid. I use the HRPOLY-X as a backup for the VU sensor and two are synched up nicely.
Once the alarm starts to beep at 10.9V, I can fly about 2 more minutes before the alarm goes solid and even then I can continue to fly for another minute or so before the quad wants to land.
If I land right at the point the alarms go solid, my 3S-2200 lipos will take a 1700ma charge which is 77% of the pack's capacity. PERFECT!!
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KopterX
Member
1. A fully charged Lipo Battery is a 4.2V/cell, that is 12.6V for a 3S Lipo.
2. I suggest about 3.6V/cell per cell for first level protection, this is 10.8V for 3S LIPOs.
3. For second level i suggest to not go lower than 3.3V per cell because you might damage the Lipo pack, for a 3S this is 9.9.
4. Put around 0.3V Line Loss (0.1Vper cell for new batteries), and do a fly test. After you land, measure again, if the voltage is higher than you wanted, increment with more 0.1V until you find the correct line loss and get the end voltage you want. But if the Lipo is in good condition, your line loss must be around 0.3V for a 3S pack. Usually this is about 0.1 volt per cell with a new Lipo and it will increase in time when the battery will be older. You should check this again after 20-30 cycles.
5. If the time between first voltage protection and second is to short increase the value at first level protection until you get about 25-30 seconds time.
Line loss is the difference between voltage of your LIPO when you fly and the Lipo is LOADED (meaning there is a current load on the battery) and the voltage measured when the Lipo is disconnected from your copter, and there is NO LOAD on the LIPO pack.
There is an alternative way. You can measure the LOADED voltage by strapping the copter to your table and measure the voltage while motors running and stick is at 50%. Be very carefully if you do it this way, propellers can easy cut your fingers off!
2. I suggest about 3.6V/cell per cell for first level protection, this is 10.8V for 3S LIPOs.
3. For second level i suggest to not go lower than 3.3V per cell because you might damage the Lipo pack, for a 3S this is 9.9.
4. Put around 0.3V Line Loss (0.1Vper cell for new batteries), and do a fly test. After you land, measure again, if the voltage is higher than you wanted, increment with more 0.1V until you find the correct line loss and get the end voltage you want. But if the Lipo is in good condition, your line loss must be around 0.3V for a 3S pack. Usually this is about 0.1 volt per cell with a new Lipo and it will increase in time when the battery will be older. You should check this again after 20-30 cycles.
5. If the time between first voltage protection and second is to short increase the value at first level protection until you get about 25-30 seconds time.
Line loss is the difference between voltage of your LIPO when you fly and the Lipo is LOADED (meaning there is a current load on the battery) and the voltage measured when the Lipo is disconnected from your copter, and there is NO LOAD on the LIPO pack.
There is an alternative way. You can measure the LOADED voltage by strapping the copter to your table and measure the voltage while motors running and stick is at 50%. Be very carefully if you do it this way, propellers can easy cut your fingers off!
ChrisViperM
Active Member
I use this:
http://www.mttec.de/MTTEC-Lipo-Waechter-BS12-Einzelzellenueberwachung-Display-dual-Summer_1
...don't know if there is a version in English.
I never got this LineLoss thing straight in my head. Isn't the only thing important to set the one alarm at a certain voltage for the 1 level and one alarm at the 2nd level ? Why do we have to fiddel with this LineLoss thing ?
I did a lot of Flybarless Helicopters and saw all sorts of settings in the Controllers, but this LineLoss was new for me.
Maybee I am just blind....
http://www.mttec.de/MTTEC-Lipo-Waechter-BS12-Einzelzellenueberwachung-Display-dual-Summer_1
...don't know if there is a version in English.
I never got this LineLoss thing straight in my head. Isn't the only thing important to set the one alarm at a certain voltage for the 1 level and one alarm at the 2nd level ? Why do we have to fiddel with this LineLoss thing ?
I did a lot of Flybarless Helicopters and saw all sorts of settings in the Controllers, but this LineLoss was new for me.
Maybee I am just blind....
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