dx7 fail safe with throttle hold ?

[jarosujo]

Hi,
for fail safe programming it is advised to apply low throotle stick. But if I use idle up low throttle stick actually means full throttle+negative pitch. Is it possible to setup fail safe with throttle hold so engine goes off even during idle up flying ?
Situation : flying 3D, problem with connection - fail safe will apply low throttle stick which means full throttle while using idle up for 3D=big crash
Thanx

[dutch_anykey]

Hi

For fail safe I temporaly changed the throttle curve in the radio settings for normal mode. (flat zero) after that i put the stick just a tad above mid stick and then bind the radio with the RX. After that is done i put back the original throttle curve in the radio.

I hope this helps.

Maurice

[jarosujo]

:dontknow

Do I understand it correctly ?
Fail safe is done during binding procedure, so you are basically doing both things always together.
So step by step:
1. 3 position switch on normal mode, low throttle stick
2. binding/fails safe procedure
3. during flight while using idle up (3 pos. switch NOT in normal) in case of problem fail safe will switch to normal with low throttle stick so engine will stop

Does it work like that ? Can receiver switch from idle up(1 or 2) to normal by itself ?
What if I use throttle hold during step 1 so it doesn't really matter what flying mode i am using cause throttle hold means engine off for all flying modes ?

[dutch_anykey]

Hi,

Assuming we are talking about the DX7:

Fail safe is done during binding procedure, so you are basically doing both things always together


Yep

The failsafe remembers all channel positions at that moment during binding. It doesnt care for switch positions. So the stick positions during binding are remembered.
So during binding if you have your throttle stick down and the throttle is zero at that time, that position will be remembered. But be carefull and check also what pitch curve you have at that stick position. I have a lot of negative pitch in normal mode. So if i would use that during binding and i had a failsafe situation my heli would fall down like a brick.

Maurice

[jarosujo]

thanx,
but i read older posts and I believe you are wrong
fail safe remembers only throttle stick binding position
the best throttle stick position for fail safe is middle stick if u use idle up for flying
it doesn't matter what curve you have during binding but what you have during flying
so if you are flying using idle up and you set low throttle during binding (even if you have zero throttle curve during binding) and fail safe emerges it's same like if nothing happend but you pull you throttle stick all the way down so you crash really hard (if you are upside down you fly to heaven :-)
there is no way to switch off engine if you are using idle ups (i believe 90 % of us) and fail safe emerges

[dutch_anykey]

Hi,


there is no way to switch off engine if you are using idle ups (i believe 90 % of us) and fail safe emerges


Well have it your way.....I'm afraid i don't understand what you are trying to say.

You are right about the pre-pitch settings. I was wrong about that with the dx7. It only memorizes the throttle setting during binding. and if failsafe kicks in it will take the last known position of the servo's

But it is still possible to have your engine cut during failsafe.....Just bind the RX when your tx is in "normal" mode. So that is 0 throttle at low stick.

I'm going to check it again on my 450 with the motor disconnected from the main gear...

Maurice

[jarosujo]

Thanx a lot for your replies,
it looks many users have similar question and got different answers.
How do you "simulate" fail safe ? (walking 2 km away with tx is not good idea i think:-)
Please share your result
What I mean is like theoreticaly there is a servo in your tx which moves throttle stick to (in our case) low position during fail safe. If you are using idle up this is usually full throttle/full negative pitch.
I hope you understand what I mean.
If its true what you are saying then during fail safe binding not throttle stick is memorized but power coming to engine.

[Finless]

Well Dutch is right about how to bind... I know the servos dont go to a fail safe setting BUT they DO go to the bind position on RX power up!
So I also make my normal throttle curve a flat 0 and put the stick at center and bind.
What this will do for you is on power up the servos will go to the center stick position rather than low or some other screwy positition.

Some might say who cares..... Well having a power loss reset myself once, I can tell you when the RX powers back up in the air you dont want it to go to some wierd swash positon!

ALso make sure you have set up the radio for CCPM before you bind as if you bind first watch what the servos do at power up! They overdrive with full aileron and elevator! So set for CCPM before binding or rebind after your all set up.

Bob

[dutch_anykey]

Hi speaking of the devil.....

Just received a new align 35 Amps ESC...the X version that means 6 volt BEC. I replaced it because the old one i didnt trust anymore. It started out that someday slow start didnt work anymore...so everything else was working. Then one day i puffed a few FET's i think...forgot slow start wasnt working anymore and tried to spool it up coming from throttle hold into idle 1....
Anyway...i received new ar6100's because i shipped the old ones back together with the tx for repair.
Installed one on my hdx450 and during flight i had a complete RX reset...unfortionatly i was inverted....
After that to be sure i put on a new align esc 35Amps....today i was testing..looked good...but at some moment i had rx reset again..rx reboot and landed safe (only hoovering 2 metres from the ground) Tried it again several times..rx keeps rebooting..tried my second ar6100..same result... Good thing i bind my RX with the changed throttle curve and 50% pitch...because it really resets to that position after a reboot of the rx....

But now i still have another challenge to find why it keeps rebooting...never had it with the "old" ar6100....

runnning 3 hs65 mg's for ccpm, 401 gyro + 9250 futaba servo for the tail....the Bec should be able to handle this right?

Maurice

[dutch_anykey]

I guess i know the answer already.....
I'll go for a seperate bec. Maybe that helps. It's still disturbing that i didnt have that problem before. Maybe my servo's and digital tail servo are wearing out...taking more amps then before.

Maurice