Switching

[Hospital_Rocket]

On a dual deploy system...

Should I use a separate switch to arm the main and the drogue? or is it more common to use one switch to turn all the electrics on at once?

 

[llickteig1]

I don't know how you would even use seperate switches for arming. Commonly, dual deploy altimeters have a single switch to power-up (or 'arm') the unit which controls all functions.

I guess if you have two altimeters or timers, then you could use two switches. You could use switches in some configuration to shunt the charges, I suppose, but that is a different discussion.

I don't use any switches at all. At the pad, I twist and tape the two wires together and push them back into the hole. One less failure point, IMHO.

You might check out www.perfectflite.com or www.missileworks.com and look at the on-line manuals for their altimeters. Then you might better understand how things are set-up.

--Lance.

 

[rstaff3]

You must be careful in selecting switched as their contacts are subject to intermittent connections under vibration and load. If this happens and the electronics reinitialize, they can get fudged up, and some may even fire the electonics. IMHO it's much safer to use switches/plugs to interrupt the continuity to the igniters. If you have multi-pole switches you could get by with one. Modern electonics should be able to run for a long time without a significant drain.

I've also done the twist thing, and sometimes use a quick connect to the payload (twist on, etc.)

 

[Rocketjunkie]

Originally posted by llickteig1
I don't use any switches at all. At the pad, I twist and tape the two wires together and push them back into the hole. One less failure point, IMHO.

I do the same thing except I leave just a little out and tape it down to the airframe. This allows disarming if for some reason you have to abort the launch.

 

[Hospital_Rocket]

OK, so I was not clear...

What I was thinking about was using two switches, one in each firing circuit. I was thinking about shunting the line to the charges until just before flight. That way if there is a timer/altimeter gaffe, the worst that can happen is to blow the output circuit on the electronics.

A