<span class="Apple-style-span" style="font-family: verdana, geneva, lucida, 'lucida grande', arial, helvetica, sans-serif; font-size: 13px; ">Hi Forum,
Just started with this hobby and building a Multiplex Mentor.
A disturbing error occurs when I hook up everything. After a sharp beep the engine starts to run at max revs.
This happens always when connecting all but leaving the Tx off (Futaba 7C 2.4 GHz)...Okay after some reading here I realize this should never be done - always Tx on first and I am damn scared off this Lipo battery too, treat it like an explosive.
BUT :
More frightening : it also happens when Tx is on with throttle lever at low steady revs : without warning, suddenly, the engine goes to max revs..
It can be stopped when I turn power lever on Tx to max and then back.
.. The first time this happened, I 've crashed the plane into a wall - loosing prop and damaging the motor mount (2 prop bits flying around like knives - luckily I told my kids to stand behind the plane !).
Thank you for sharing your experience with me !
Best regs, Peter</span>

Sounds like you need to reverse the throttle channel on your transmitter.
Most ESCs have a safety feature to prevent that from happening. Appearantly that cheap ESC with the Multiplex does not.

Well, that's not necessarily true.

Even expensive ESC's will not know if the throttle is reversed.

Do what you need to do to set the thing up, but WITHOUT a prop. Then, set up your throttle settings, and in this case, reversing the controls to make sure idle is actually idle and not full.

I have five stiches on my right idex finger that proves what I'm saying is true. Plug everything in but do not put the prop on the motor. Then, turn things on and work the throttle through the arming sequence. You should be able to go to full, hear a sequence of beeps from the motor/esc then to idle with another sequence of beeps... this should be outlined in the manual for the motor/esc... and then when you move the throttle again, it should signal the ESC to ramp up the motor according to the throttle settings.

This is pretty much standard with most of the motor/esc pair that I've worked with.

CGr.

What I meant was most ESCs, at least the ones I have had, will not arm unless it sees the the throttle at its lowest setting and would not have armed at all with the transmitter off as happened to him.

HMMMMM!!!!!!!!!!!!!!!!!!!!!!!


Sounds like a good reason to do your testing without the prop attached Make sure everything is hooked up correctly before adding either propellers or rotor blades its a whole lot safer. Glad no one was injured

Yup, Steve. That's the lesson I learned.

Thanks guys, seems like problem is solved now by making sure to switch Tx on as 1st thing and as last thing and not adding the Rx battery as this is not needed ...
yes I finally read the manual.. in this day and of plug and play Macs and Quick Start Manuals good habits tend to be forgotten..