ACS Ignition Keyswitch with Elec. Ignition and one mag?

I was perusing some AutoCAD files for Aeroelectric connection that showed the wiring for the 5-position keyswitch but they were all for dual mags. My question is it possible to use the keyswitch if you have one electronic ignition and one mag? The scenario in the CAD files that shows one and one uses two toggle switches (which I notice a lot of guys do) but I already own an ACS keyswitch and would like to use it...

Please advise before I cut the hole in my panel...

Yes

Sorry, I dont have my papers here, they are at the airport but I had the same issue and it took a long time to find the answers. I have one lightspeed 2, and one slick mag with impulse. If the lightspeed is current, Klaus said it should be used with the mag for starting. (engine builder suggested only use mag for starting). Klaus said that is the old software. Anyway, I did use the key switch and will do my best to get the drawings home and scan/send them. They work well for me. Back at you later today.

I have the same setup as you, Rick. I too would like to get the schematic for the ACS key switch.

Thanks much!

On my friend's Lancair when I wired-in one LSE PI I used shielded wire from the magneto and used only the shield ground from the magneto case as the ignition ground lead. There is a coaxial fitting that can be used on the P-lead at the magneto end that ties the shield of the shielded wire to the case of the magneto. The LSE can use the same connection since it is protected from the magneto's high voltage spikes on the P-lead. Never ground the ignition ground on the ACS to the airframe as that is inviting ignition noise into the radios.

What I did.

The acs keyswitch has the following pins on the back.
Here is how I wired it.
BAT - obviously to battery (powered off main bus with 7.5 fuse)
S-to starter contactor
BO-nothing
LR-nothing
GRD on outside- nothing
R-center of shielded wire to pin one from lightspeed plasma 2 box
GRD (center) -Shielding from lightspeed R wire, AND shielding from shielded P lead off left mag
L-center of shielded wire from left mag

NOTES-no jumper on keyswitch, shield both mag and EI wires to center pin.

As per Klaus at Lightspeed " p lead option with the plasma cdi allows you to connect the electronic ignition to a standard ignition switch as if it was an impulse coupled mag. The impulse coupled mag does not need to be disabled during start. Since you have one impulse coupled mag you should start on both. That means NO jumper on either side. Since we made some improvements in Dec 2004, there is no longer any reason to disable the Plasma cdi during start, even when the battery is weak. Never use a fuse to protect the ignition system, you need a breaker in the panel for the cdi. You need to wire your plasma CDI per our manual regardless of what hearsay is on the forums.

SO...your mission may vary, and Klaus would rather you contact him than listen to forum chatter. Seems to work but I am NO electrical expert...but it starts when I turn the key!

PLEASE IF ANYONE SMARTER THAN ME CAN ADD, CORRECT, CLARIFY.....PLEASE DO SO. This is the best I got from all my research into this type of config.

Rick, thanks, that helps a lot.

Ground screw at keyed switch-nagging thought

After a search I pulled up this thread. I have same setup at Rick's (2 posts up), i.e., left mag and right electronic ignition (e mag) and I have wired it like Rick describes. I am finishing up wiring and have a nagging thought that the ground screw on the keyed ignition switch should be grounded via grd wire to the aircraft ground as per the instructions that come with the switch (a standard off-L-R-Both-start keyed switch).

So far to this grd screw I have the shielded wire from the L mag and shielded wire from the e mag. The length of the ground screw prevents me from attaching a 3rd connection for the aircraft grd wire.

Bottom line: keyed switch ground screw to aircraft ground or not? Is there a right way? The mag shield is grounded at the mag end ground screw and if it is also grounded at the switch to aircraft ground wouldn't this setup a ground loop possibly causing radio static?

Jim
RV9A

jimbo said:

The length of the ground screw prevents me from attaching a 3rd connection for the aircraft grd wire.

Click to expand...

Get a longer screw.

Jim, I am pretty sure according to the AeroElectric Connection you do not connect the key switch ground to the aircraft ground. There was also another comment on the forums here suggesting the same. Maybe someone who has done this can weigh in...

jimbo said:

After a search I pulled up this thread. I have same setup at Rick's (2 posts up), i.e., left mag and right electronic ignition (e mag) and I have wired it like Rick describes. I am finishing up wiring and have a nagging thought that the ground screw on the keyed ignition switch should be grounded via grd wire to the aircraft ground as per the instructions that come with the switch (a standard off-L-R-Both-start keyed switch).

So far to this grd screw I have the shielded wire from the L mag and shielded wire from the e mag. The length of the ground screw prevents me from attaching a 3rd connection for the aircraft grd wire.

Bottom line: keyed switch ground screw to aircraft ground or not? Is there a right way? The mag shield is grounded at the mag end ground screw and if it is also grounded at the switch to aircraft ground wouldn't this setup a ground loop possibly causing radio static?

Jim
RV9A

Click to expand...

I have wired two airplanes with this setup - L impulse magneto and R a Lightspeed ignition. I did not connect the switch to the airframe near the switch; I used shielded cable to the mag and the braid was attached to the magneto case with the center wire connected to the P lead. Both Lightspeeds have the ignition key option - the RV has a Plasma 2+ and the Rocket has a Lightspeed 3. So I use both the Lightspeed and the mag when starting and have not had any trouble with starting in either airplane.

Matt is correct, I just checked and the Aeroelectric Connection manual does not show an aircraft ground wire to the switch ground screw. What confused me is the diagram and instructions that came with the keyed switch that does say to ground to aircraft at the switch ground screw.

Jim

use toggle switches

I originally used an ACS ignition switch with my left impulse mag and right LSE II. After about 6 years and almost 600 hours I started having drained battery issues when the aircraft sat without flying for a couple of weeks. After putting a new battery in, I still had the same problem. Next I thought I had a bad ignition switch and replaced that, but still the same problem. Then I thought it might be the LSE box itself, so I sent it back to Klaus who assured me it that it was fine. What I finally discovered was that the LSE box mounted on the firewall was being grounded even when the ignition switch was in the off position. Over the course of six years the bolts mounting the box to the firewall had worn away the coating on LSE box that allowed a ground to keep the LSE ignition powered on continuously. I solved the problem by rewiring the LSE and mag to toggle switches and using the ACS ignition switch as a starter switch only.