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        Help! Do you use a on/off switch on battery planes?

#1 fltekdiver Sep 24, 2010 01:47 PM

Do you use a on/off switch on battery planes?
 
Im building my first 51" Slick, and on Nitro planes, I used a on/off battery swtich to turn everything on.

So you still use one on Lipo batterys?

#2 everydayflyer Sep 24, 2010 02:03 PM

No ,one more source of resistence and another potencial failur point. Some use shorting (make contact) plugs which are better,IMO. I just use a Throttle Lock on my transmitters and stay clear of the prop while a battery is connected.

Charles

#3 abenn Sep 24, 2010 02:05 PM

I never use an on/off switch with electric power. Inserting and removing the power battery is my switch.

Sometimes the ESC comes with an on/off switch, but even then I usually just cut it off and solder the two wires together permenently. The reason is that, even if the throttle signal from the receiver to the ESC is cut (which is what that switch does), the ESC still has power from the main battery so, in theory, might be triggered by interference or some other spurious signal to start the motor.

If I'm using a separate receiver battery (which I don't in any of my current models) I would use a regular on/off switch on it, just so that I can power it down while the model is resting with the motor battery disconnected. But, to avoid the ESC being triggered by stray signals, the switch should only be switched off after the motor battery is disconnected, and it should be switched on before the motor battery is reconnected.

#4 fltekdiver Sep 24, 2010 02:23 PM

10/4, thanks, whats the throttle cut for?

I have a DX-7,. should I use it?

#5 everydayflyer Sep 24, 2010 02:35 PM

Throttle cut ,Throttle lock different terms used by different Transmitter / users to mean the same thing is a setting that Locks Throttle position to a point where moving Throttle Stick has Zero effect. Mine is set for -5% and while ESC will arm motor will not start until Throttle Lock is switched off.

Charles

#6 fltekdiver Sep 24, 2010 02:40 PM

Thanks so the plane will not start at full throttle then huh?

#7 rampman Sep 24, 2010 02:50 PM

I use switches on my RX pack on my bigger planes if I can't access the pack easily.
All of my new built planes will have a shorting plug as Charles mentiones above.

To anyone that uses a switch, be sure to mount the switch so the "on" is towards the tail. I have a FB that lost a plane when his canopy blew off and turned the switch off on its way off the fuse and towards the tail. *eek*

Rick

#8 rampman Sep 24, 2010 02:52 PM

fltekdiver - it helps in case you accidently bump the throttle stick when you bend over to do something to the plane....
I have another FB with a 6" long scar on his left leg from a prop. About 30 staples later... *eek* again.

Rick

#9 fltekdiver Sep 24, 2010 02:55 PM

Quote:

Originally Posted by rampman (Post 16134034)
fltekdiver - it helps in case you accidently bump the throttle stick when you bend over to do something to the plane....
I have another FB with a 6" long scar on his left leg from a prop. About 30 staples later... *eek* again.

Rick

Hmm, thanks for all your help!

So how and where is the throttle cut, it's a swtich on the DX-7?

#10 mexico Sep 24, 2010 03:00 PM

Quote:

Originally Posted by rampman (Post 16134009)
I use switches on my RX pack on my bigger planes if I can't access the pack easily.
All of my new built planes will have a shorting plug as Charles mentiones above.

To anyone that uses a switch, be sure to mount the switch so the "on" is towards the tail. I have a FB that lost a plane when his canopy blew off and turned the switch off on its way off the fuse and towards the tail. *eek*

Rick

I just installed a switch harness this week and put on - forward. I had not thought of that.

I programmed a throttle cut last year. First time I accidentally hit it during a blender was the day I removed it from my radio.

#11 RobC(UK) Sep 24, 2010 03:04 PM

I don't know about Spektrum but on Futaba pushing the Throttle Cut button simply moves the servo to the end of its travel to completely close the throttle on the carburettor and will return to the idle position once released.

#12 mexico Sep 24, 2010 03:10 PM

The function is throttle cut but on an electric plane it is a mix programmed in so that a switch will turn the motor off and make the throttle stick dead. Mine was programmed on a Fut 7C.

#13 Bongo Fury Sep 24, 2010 07:31 PM

Quote:

Originally Posted by rampman (Post 16134009)
.... To anyone that uses a switch, be sure to mount the switch so the "on" is towards the tail. I have a FB that lost a plane when his canopy blew off and turned the switch off on its way off the fuse and towards the tail. *eek*

Rick

Good point +2. For anyone interested, suggest the opposite for a ground RC. Most hard impacts are head on, sometimes this will move the switch forward from inertia.

Dave

#14 jrb Sep 24, 2010 09:20 PM

5 Attachment(s)
I use switch between pack and UBEC along with a arming plug to the ESC -- see diagram:

This scheme also allows me to charge w/o removing packs -- mostly A123s.

Also on is aft -- won't go off if bumped on a hand launch!

A shunt can be used for arming to make an installed measure of amp; loop of wire and clamp-on meter too.

Also, volts under load can be measured via charging port.

#15 everydayflyer Sep 24, 2010 09:29 PM

Quote:

o on is aft -- won't go off if bumped on a hand launch!
Well that depends. Around 18 years ago the father of one of my students pushed the switch off on his son's trainer during a hand launch and that swith was aft to arm. It was otherwise a perfect launch however and the plane climbed out circled into the clouds and was never seen again by us. I just set the Transmitter down and watched it fly away.

Charles


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