Missleworks has a good dipole switch that's made to order for easy on/off switch for ejection charges or staging igniters that can be wired to shunt in the off position. It is turned on/off via small flat blade screw driver so it fits the bill that anyone can disarm it without keys or phono plugs etc..
it has 4 solderable connections 1...2....3....4 and is normally used to lock in 110v or 220v
In the 220V position 2-3 connect In the 110V position 1-2 connect and 3-4 connect
arrange your wiring such that the igniter/ejection charge leads are on 2 and
3that way they are shunted (twisted together) in the "off" or 220V position
2-3 and are isolated from the altimeter etc. on power up.the wires from 1 and 4 go to the altimeter, accelerometer, stager unit.(whatever) so each lead is armed in the 1-2 and 3-4 arrangement when the switch is in 110V position
I use nylon screw down terminal strips to connect them up.
Koen