[NSRCA-discussion] LiPO Receiver packs

[Bob Richards]

Fred,
   
  All true. The good thing about Lipos is that the discharge curve is much more linear, where the Nicad is relatively flat before it dumps. Using a good voltmeter, with an appropriate load, will tell you pretty quickly how much is left in a Lipo.
   
  Bob R.
  

Fred Huber <fhhuber at clearwire.net> wrote:
          There's a "trap" in using a LiPo and regulator in that they work so well... right up until the LiPo voltage drops below the regulator cut-out. (where it just passes the full LiPo voltage to the RX)  At that point you might have 1 min left... The LiPo will be below safe minimum voltage (damaging the LiPo) and when the throttle falesafe indicates the RX is getting less than 3.8 volts... you are about 10 seconds from total loss of control.
   
  Use of 3S LiPo in a TX that has a low voltage alarm can be a similar trap...  The alarm won't sound until the LiPo is ready to drop to 0 volts. (except the Futaba MZ's which are designed to use LiPo and should have an appropriate alarm setting)
   
  I have read of a few incidents of people thinking they were OK for another flight or two, and the LiPos dumping.  You have to check the LIPO voltage before each flight, and you have to know what those voltages mean in relation to remaining capacity.
   
  The incidents I have read about were ALL due to lack of charging and lack of checking remaining capacity (or failure to understand that 9.6 V on the TX voltage indicator is NOT GOOD when using 3S LiPo)  I have not heard reports of the regulators failing.  Just operator errors. (failure to recharge)
   
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