Lipo Low voltage alarm for spectrum receiver?

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Lipo Low voltage alarm for spectrum receiver?

11-03-2012, 05:36 PM Junior Member Thread Starter Join Date: Nov 2012 Location: Harker heights, TX Received 0 Likes on 0 Posts Lipo Low voltage alarm for spectrum receiver?

So, I just lost a hangar 9 P51 on its maiden flight due to what I believe to have been a low voltage cut out on my spectrum receiver due to a failed life batt. My flaps deployed and retracted on their own, I believe three times, before impact and the plane also began a right turn on its own while I was struggling to turn base to final and get it back to the ground. When i finally got it to final and was roughly 10 feet above the ground the flaps deployed the third time causing the plane to nose straight up and stall nose first into the ground. When I got the battery back I tested it on a hangar 9 tester and found that both cells failed with a 2 amp load. As a result I will never use life again and am solely using lipo flight packs with voltage regulators and low voltage alarms.

I know that critical low voltage for a lipo batteries is 3.0 per cell or 6.0 on my two cell lipo flight pack. My question is at what voltage should I set my low voltage alarm to sound to ensure that my receiver never locks out again. I am only using this battery to push the servos and receiver on nitro planes.

Thanks in advance for the help

Kprice52001 11-03-2012, 08:18 PM

My Feedback: (2) Join Date: Jan 2002 Location: Rochester, NY Posts: 4,760 Received 2 Likes on 2 Posts RE: Lipo Low voltage alarm for spectrum receiver?

So, I just lost a hangar 9 P51 on its maiden flight due to what I believe to have been a low voltage cut out on my spectrum receiver due to a failed life batt. My flaps deployed and retracted on their own, I believe three times, before impact and the plane also began a right turn on its own while I was struggling to turn base to final and get it back to the ground. When i finally got it to final and was roughly 10 feet above the ground the flaps deployed the third time causing the plane to nose straight up and stall nose first into the ground. When I got the battery back I tested it on a hangar 9 tester and found that both cells failed with a 2 amp load. As a result I will never use life again and am solely using lipo flight packs with voltage regulators and low voltage alarms.

I know that critical low voltage for a lipo batteries is 3.0 per cell or 6.0 on my two cell lipo flight pack. My question is at what voltage should I set my low voltage alarm to sound to ensure that my receiver never locks out again. I am only using this battery to push the servos and receiver on nitro planes.

Thanks in advance for the help

I have been using LiFe batteries for some time. 2cell LiFe batteries drop to 6.6v per cell throughout the Discharge Cycle. When they reach Critical, they drop down immediately. I have my warning set to 6.5v. I would not give up on LiFe batteries. They work fine. Keep them charged regularly. They are not as predictable as LiPo cells when it comes to measuring the voltage as they Discharge. Keeping track of the Time used is more important.

BuschBarber 11-04-2012, 07:37 AM Senior Member Join Date: Dec 2001 Location: , UT Posts: 12,630 Received 4 Likes on 4 Posts RE: Lipo Low voltage alarm for spectrum receiver?

So, I just lost a hangar 9 P51 on its maiden flight due to what I believe to have been a low voltage cut out on my spectrum receiver due to a failed life batt. My flaps deployed and retracted on their own, I believe three times, before impact and the plane also began a right turn on its own while I was struggling to turn base to final and get it back to the ground. When i finally got it to final and was roughly 10 feet above the ground the flaps deployed the third time causing the plane to nose straight up and stall nose first into the ground. When I got the battery back I tested it on a hangar 9 tester and found that both cells failed with a 2 amp load. As a result I will never use life again and am solely using lipo flight packs with voltage regulators and low voltage alarms.

I know that critical low voltage for a lipo batteries is 3.0 per cell or 6.0 on my two cell lipo flight pack. My question is at what voltage should I set my low voltage alarm to sound to ensure that my receiver never locks out again. I am only using this battery to push the servos and receiver on nitro planes.

Thanks in advance for the help

There are different LIFE batteries for rc users ,on the market - some are intended for low power consumption! these will have a lowC rating on the cover.
Trying to predict the low cutoff on LIFE is tricky at best .
My own tests show that somewhere around 3 volts- per cell -they quit.
remaining power available starts to show up at about 3.1 per cell. A bulb attached as a load test, starts dimming - a little.
I use #1157 small tail light bulbs as loads to see what is happening
very easy to use and very reliable test. Unless one is blind.
In use, 3.2 is BOTTOM of use for our purposes as the remaining time before power goes from 3.1 to 3.0 has to be a known time at a known load .
So
Use high C type FEO4 (LIFE) and time use in your own application and stay within the time found to leave a 3.3 reading on the pack.
Using LIPos and low v cutoffs works as long as you have really good cutoff /measuring devices . also running a LiPo to 3 volts is NOT good practice
On an electric powered model the cutoff should be higher - - properly adjusted the LiPo after the flight should read aprox 3.7 volts -for good LiPo life.
Pushing LiPos down to 3.5 or lower, kills em quick!