ORIGINAL: Silver182
ron...
I have a twin vectored D/F SU-34 Full Back from Hobby Lobby...it flies great. The problem I'm having is Battery failures. It comes with a 4cell 3000ma 20c Lipo pack. Today I measured the Watts..close to 1000 actually 960. The amp meter said I was drawing about 63 amps.
OK I tried a Rhino 4cell 20c 3700ma pack today..and it provided almost full power for a full 4 minutes..something that I can not get out of the batteries that come with the SU-34. Both have 20c displayed on the pack but one is a much stronger and actually works.
What kind of battery pack should I be using for long lasting performance.
Lee
Hey Lee, it's Rob. I'm the one who loaned you the 3700ma Rhino. I got home and finished charging that pack, it ended up taking 3112ma total, after the 4 min flight. That explains why your packs are dead already, it damages the LiPo cells if over-discharged. Your 4 min flight took the batteries all the way down, being only 3000ma capacity.
So, either one of two things: Either the designers of the plane never intended the plane to be flown at or very near full throttle the entire time, or their study on the proper capacity packs for the power system are flawed.
In either case, once you receive your 3700 packs, you should be ok as long as you don't go past your 4 min flight time, as there should be somewhere close to 588ma left in the pack, not over-discharged.
I also strongly recommend increasing the wire size from the ESC splices to the battery connector, as the increased resistance from the wires geting so hot will also stress your power system. In my opinion, 14ga wire isn't sufficient to sustain a constant 65 amp draw at over 15 volts, 12ga would be much better. You might even notice a slight performance increase also.
Rob.