Power completely went offline! ???

[JasonRP_7743]

Well, today was first trim flight of rebuild Blade 400 (I call it a 425, as it has g210, ds76 and ds76t, and 35A ESC from a blade 450, but frame and head of a blade 400)...

All was going well, but as I had realized I had forgotten to set the timer, I got ready to land to put in a fresh battery after a few minutes of hover in idle-up mode.

About maybe 4 inches from the ground, the heli just throttled off and landed with a thud.. Pretty hard landing, but flat on the skids, and as near as I can tell, no damage/no boom strike, blades all look untouched/undamaged, tail rotor still like new, no sign of damage. My guess is these helis can take a hard set down on the skids with no problem as long as there is no blade strike.

Anyways, I nervously hit throttle hold, and started working the cyclic- no joy whatsoever, no movement. That's when I realized, the heli had powered off. After a few seconds, power went to the servos, and the heli started to initialize. I moved the servos a bit, then unplugged the battery. When I plugged my blinky into the battery- all 3 cells were around 3.89- plenty of power.

I should note: This battery had a deans connector on relatively short leads.. I soldered on an eflight connector and two short wires, with heat shrink. I was pressed for time, and was concerned that I did not get the solder joint hot enough- but it did not look like a cold joint. I re-heated, and then heat shrank/finished the job. Also, the ESC was brand new outta the package for this flight- 35A Eflite ESC- same part number as used for Blade 450 3D..

The only other clue was, the battery was very warm (not burning hot to the tough, but was warm/hot) after the flight. Motor was also hot, but not burn your finger kinda hot. ESC did not feel hot.

So, what do you folks think happened? Bad solder job on battery connector or spliced in wires (too much resistance?)?? Bad ESC? Bad Motor? Where do I start to debug? I think perhaps if I hadn't already been in landing final feather, it would have been a crash.

Your thoughts appreciated!
Jason

[Bee_random]

A strange one. Id start the debug by seeing if you can repeat the problem, before making any changes and then only changing one thing at a time before testing. Assuming you can repeat the problem.

[JasonRP_7743]

Anyone know what the spectrum receiver would do if it lost power (or signal)? Would it chop throttle to 0 and leave all other servos as is?

[bundydeity]

i seem to remember when i very first got my b400 i once had power to the heli and the transmitter was off - i cant remember the specifics, but i do know my heart rate skyrocketed as the heli seemed to go into full throttle - once transmitter was back on and had initialized was all good
not sure about servo movement i was too busy panicking trying to shut down!

so my guess would be no signal = full power? someone correct me if im wrong but

[jabu32]

no signal "should" i believe cut the motor

[wulfrun]

Originally Posted by JasonRP_7743

Anyone know what the spectrum receiver would do if it lost power (or signal)? Would it chop throttle to 0 and leave all other servos as is?

It kills the throttle on signal loss. On "plank" settings it also seems to give slight forward-elevator and slight left rudder and aileron - I'm guessing it's aiming at a left-hand gentle spiral down. Haven't tried the heli setting but I assume it does something similar. That's for the AR6100e anyway.

[LowSpark]

Pinion is too tight to the main gear...


maybe????

[JasonRP_7743]

Flew it today a bit, battery that was known good- no cut offs. I think it may just be my crappy soldering job..

[Excalibur3]

My sr fell from the sky last night . Turns out it was a broken wire on my motor.