Rotax 582 99

To the best of my understanding;

Your ignition circuit/electrical generating system is separate from the general electrical system that charges the battery and aircraft systems (avionics, etc)

However the systems usually share a Common Ground/-Neutral. either through the airframes/chassis and/or via dedicated neutral wiring circuit.

When the ignition system is armed/live, the only way the electricity can make its way to ground, is through the spark plug, jumping/arcing across the terminals, creating a spark.

When you want to stop the engine from running you can either stop the fuel flow OR stop the spark. 

For LyCons, the pilot usually stop the fuel flow at the carburettor(mixture control).

Standard Rotax installation's, do not have pilot controlled fuel mixture, instead ignition OFF is is used.

When the ignition switch is turned to OFF for both ignitions, the + Positive circuits are allowed to make contact with the - Negative/Ground circuit, giving the electrical energy an alternative/prefered rout, taking the energy from the spark system.

You should be able to connect your ignition "kill" circuit wires to whatever Common Ground/ - Neutral system your aircraft has. 

IF your ignition/charge system does not share a Common Ground/ - Neutral system, you will have to connect your "kill" wires back to the ignitions generating system (not the battery).

Hope this helps and does not cause further confusion.

😈

Hello Sean..

Thanks for the info..

My systems are independent of one another.

(engine run+starter)

My plan was to ground both wires to my selfgrounding starter solenoid (which shares) wiring through my starter sys back to Battery...

Any thoughts on the above?

Hi Joseph,

You should be able to connect your "kill" (Rotax call them "shorting") wires to any point on your Common - Negative/Ground . This circuit is often has a point (sometimes more than one) where a number of wires will connect to it - known as a Buss. It is common to find a -Negative Bus under the instrument panel.

The - Negative circuit will make its way to the - Negative Terminal on the battery. 

The engine casing/crankcase/cylinder heads/etc will be part of the - Negative circuit - this includes the starter motor casing.

The key to good 12 volt electrical system is clean/tight connections (good contact), especially those of the -Negative circuit.😈

Awesome..

Thanks Sean..

I appreciatenall.the help sir..

VR

Joseph

Hi all

Be sure that you have 2 switches, one for each ignition.  You can't contact them both together in one switch.  This igniiton is a normally hot system, it must be grounded to stop the spark on a running engine.  (The same as a type 912) 

Cheers