gary jp4
Senior Heliman
Location: Nashville, TN, USA
| From the Blade 400 manual.
| Quote |
| Li-Po cells should not be discharged to below 3V each under load. In the case of the 3S 11.1V Li-Po battery used for the Blade 400 3D, you will not want the voltage of the battery to fall below 9V during flight.
The ESC installed on your model features a soft low voltage cutoff (LVC) that occurs when the battery reaches 9V under load. When the soft cutoff occurs, the ESC will automatically reduce power to the motor (regardless of the power level you have set with the throttle stick/curve) in order to prevent the voltage of the battery from dropping to below 9V. After the power is reduced and the voltage rebounds to above 9V, the ESC will automatically return power to the motor until the battery reaches 9V again. This process will continue to repeat, sometimes causing the motor/power to pulse rapidly, helping to provide a visual and/or audible indication of the low battery voltage. However, in some cases it may be difficult to detect pulsing of the motor/power, so we suggest that you be extremely aware of the power level of the Li-Po battery during flight. If at any time the helicopter begins to require more throttle than typical to maintain hover or flight, or has lost significant power, you must land the helicopter IMMEDIATELY to prevent a sudden loss in power that could result in a crash.
And although the soft LVC of the ESC will help to prevent deep (below 9V; 3V per cell) over-discharge of the battery, it is not recommended that you continue to run the motor for an extended length of time after landing and/or noticing a loss of power. Also, routinely discharging the battery to the soft LVC can still cause permanent damage to the battery, resulting in shortened flight times, loss of power output or failure of the battery entirely. It is recommended that you use the timer function of your transmitter to keep the duration of each flight consistent and to prevent reaching the soft LVC each time you fly.
We suggest an initial timer setting of 4 minutes and 30 seconds. And although it is possible to achieve longer flight durations safely depending on the performance of the battery, flying style of the pilot and other factors, we suggest using this timer setting for the first few flights. You can keep track of the flight duration on subsequent flights and adjust the setting of the timer, as you prefer.
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And that is with a 9.0v cut off. So there you go.
All the stuff about using a timer would be even more meaningful if you add the 80% rule and know how much you are putting back in with each charge.
T-Rex 450 SE V1, 430L 13t, Align 35A ESC, 325 Pro, K&B, JR 6102DX6, GY401, 9650, HS-65MG'S. |
