I am a newbie(just one year in helicopters and r/c equipment), and power options seems to be a hot always talked about subject. I have not seen a definitive route that people go by, I think causing HUGE confusion, and I believe crashes are happening due to this topic. I would like to see some professional answers with hard documented statistics.
I am confused by the setups people are using with flight packs, separate power for electronics, and back up guards. On my 550x it is a 6s system where I am running a 6s 5200mah flight battery, with a cc BEC pro hooked up to a 2s 1350mah to power the Rx and servos. The servos I run on the 550 are savox cyclic and tail. They are not HV servos so I have the BEC regulating @6.0V. That is way below the nominal output of the 2s lipo @7.4V, so the step down gives me at least 2 to 3 flights before I need to charge the Rx pack. In that setup I know I always have steady power to the servos. Both birds are using a AR7210 BeastX.
Now into my new Synergy E7SE. Its a 12s system. It uses 2 flight batteries 2x(6s 5200mah), and has all true HV cyclics and tail rated at 8.2V for tail and 8.4V for cyclics. Now if I run the same mannor where the Rx is direct to the 2s battery, it is physically impossible to utilize the true potential of torque and speed with that setup due to the nominal discharge of a 2s lipo. With the 550 not an issue from the BEC step down, but with this E7, I want to use the servos or why even waste the money on HV's? If I have to charge the Rx pack EVERY flight just to have HV for 1 minute or less, sorry but I see that as a complete waste of money. People will say if you run the servos at their HV potential, they won't last long? That seems again not smart. Why would a servo company make a product that you can't use to full potential? It makes good sense to me(but I was shot down with this idea) on a heli that has HV servos to run a 3s 11.1V battery to power electronics through a BEC to step it down to maintain 8.2V so I always have constant even power to servos, and can utilize their full potential. I think that people are crashing helis from direct hooking to a 2s lipo, then getting brown out due to inadequate voltages where then one or more servos brown out causing a crash, and how are you going to tell what caused it when you have a pile of carbon fiber in front of you? I don't like the idea of hooking BEC up to one of the flight packs due to....what happens if you burn up the esc, which shorts out flight batteries? I thought that's why we put in separate power for electronics, to eliminate the possibility of not being able to auto in with no flight power. I understand also about the scorpion back up, and I have one and plan to install for the third method of a backup power supply in case the Rx power craps out. I am not a sponsored pilot, so I can't afford to be digging holes with my E7. Maybe if Synergy would sponsor me, this would not be a subject for discussion...lol. Please will someone chime in and help get to the bottom of this always forgotten and never resolved power issue. We are so focused on servo stats, that we overlook the servos are not running at HV numbers where unless you have telemetry, you would never know what voltages your RX and servos are running on, and flying 3D, I don't have time to take my eyes off the bird to check voltage numbers.
