Lightspeed P Lead

I am using a standard fuse bus and not CB's, can I bring the P lead wires into and out of one ?fast-on? connector at the fuse bus or should I use an in-line fuse to avoid this join ? what is the acceptable way of doing this and what do I do with the shield ? Pics would help if you have them.

Thanks

Martin

Hmmm..

Your question is rather obtuse as 'P' leads are assoiciated with mags and lightspeed ign does not have a 'P' lead, just a power/ground wire. You can run a shielded wire from the fuse block to the Ign switch and then to the LS box. I ran mine this way for a long time and worked just fine, carry the shield across the switch as shown in the LS documents. Ground the shield at one end.

Not from the fuse block if it is controlled by the master switch.

Lightspeed wants the power to come right from the battery to the mag (key) switch so if you need to shut off the master, you WILL NOT shut off the Lightspeed ign.

By the book is best I think

Two correct posts so far so I will just reword them for a bit more clarity.

There are two ways to switch on/off the LS ignition. One is by interrupting the shielded 18ga. power lead that comes into the CDI on the input plug. The other option is a wire that comes out of the CDI output plug and goes to the keyswitch in the place of the original ?P? lead from your departed magneto.

The power lead needs to be directly hooked to the battery then go to a ?pullable? breaker, (then possibly a switch), then to the CDI. The power wire shield is the negative half of the 12V supply.

I grounded this shield on both ends so as to add redundancy to the ground. I also substituted a toggle switch breaker for the pullable breaker, 'cause I had 'em.

I think the reasoning for the direct battery hookup is to diminish the chances of power interruption and minimize the noise and voltage spikes going to the CDI.

I am no expert by any means, but I think that each additional wire junction you use will diminish your reliability by just a bit. Deviating from the way that Klaus wants them hooked up is putting the "experimental" in an area that is critical to continued flight.

Good luck.

Clarrify

Apologies for the use of the word "P" lead, I guess it's just become a generic term.

The reason for my post is that Klaus at Lightspeed said not to use a fuse but I guess he has said this because of the possibility of shutting the bus down. My intention was always to use the Battery Bus (always hot) so in this case, use of a fuse on this bus should be OK as it cannot be shut down. So, the wiring should go something like this; from Plasma Input; to toggle switch, to battery bus (5A fuse).

Thanks

Inline fuses for me

Hi Martin,

I will be taking the LSE PLASMA shielded power cable all the way back to the battery (and AUX battery in my case, via a diode). Shield to battery -ve terminal and core to battery +ve terminal. I intend to connect inline fuses close to both +ve terminals. I'm using CBs for both my power busses but the PLASMA will be independent of the busses, controlled by a toggle switch.

Hope that helps,

p.s. Just spotted that this posting brought up my century! - post no. 100

Thanks

Hi Steve,

Yes, great help - in line fuse makes sense.

Martin

p.s. Only 100 posts, you need to keep up! It's probably because you spend so much time on RVSQN - that said, they couldn't do without you so guess you'll have to keep posting there, anyway I think you should share you knowledge equally between us so expect to see you reach the 200 soon!