dennisB

My Feedback: (4)

I need some help with the electrical setup on my GP Extra. The setup is: 2 Futaba digital hi torque servos on the elevators, two on the rudder, one Futaba std on the throttle, one on the choke, with a 1500 ma battery AND 4 Jr digital servos on the ailerons connected to Futaba MSA 10 (like a JR matchbox) with a 900 ma battery and switch harness. The problem is the batteries run flat in about 15min. during controls testing. Linkages do not appear to be binding although there is some buzzing while at rest. Are these batteries way too small for this setup, or is there maybe another problem I haven't thought of? Any ideas or input would be appreciated.
Thanks to all,
Dennis

FHHuber

The batteries SHOULD handle it... Might have them cycle tested to be sure they aren't bad.

More likely, there's a matching problem somewhere, causing a pair (or a couple of pair..) of servos to fight each other. If you can, put an amp meter in line with servos looking for which are drawing excess current. (amp meters are cheap... model railroad type works well.)

daveopam

My Feedback: (9)

If you remove the linkage and leave the control horns you can see if the servos are fighting. Digital servos kind of sing is the best way to describe it and thats normal. They kind of sound like an old gyro. Analog servos will chatter if under a slight load. The 1500mah battery might be a little small since the digital servos take more juice. Even so 15min seems a little short. Puting them through a cycle like Hubber suggested would be a good idea either way and a good place to start. later daveo

FHHuber

GHe sent me an e-mail... seems he charged the high capacity batteries overnight using a standard Futaba charger

appx 30% charge for the 1500 mah pack... (if he did that one without Y'ing to the 900...) Which with a NEW pack... the first 20% gives essentially no charge... he had nearly flat batteries to start.