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Wiring in a Kill Switch

Wiring in a Kill Switch

Wiring in a Kill Switch

(OP)
I need to do some work on a 1940's Citroen.
Car is only being used in summer and when the sun is shining, and it's a small 6V battery so it gets drained quickly.

The owner asked me to take a look at it, as whenever he wants to drive it he calls me to connect/disconnect the battery negative cable (as I do also most of the other work on the car). A kill switch might come in handy here, both for him as for me.

Now, I know these things from jetskis and such, and started looking for an automotive one. It appears they kill the live feed? Would there be any reason not to put it in the negative/earth lead? Mind, it's an old car, so no ECU, no other electronic gizmo's, only lights, coil and some gauges and that's about it...


RE: Wiring in a Kill Switch

The switch you show is primarily for racing applications...Other things, too but, mostly race cars is where I see them.

Just about any NAPA, Auto Zone...whatever, has battery disconnect switches that are more appropriate for your intended use....Cheaper, too.  Harbor freight carries a couple.  AND, yes you can put a switch on the "ground" terminal, or just remove it from the battery post...

http://www.amazon.com/dp/B000COO1P4/ref=asc_df_B000COO1P4929352?smid=ATVPDKIKX0DER&tag=googlecom09c9-20&linkCode=asn&creative=380341&creativeASIN=B000COO1P4

My old Healey had one on the battery from the factory.

Rod  

RE: Wiring in a Kill Switch

(OP)
That one seems good enough for what it needs to do...
Will see to get one of those.

I ment to put it in the ground lead, however would there be any advantages why, in race cars, one would put it in the live feed? As I can't really see much of a difference...

RE: Wiring in a Kill Switch

Yes there are advantages.  Location of the battery ground in relation to driver. Cars equipped with generators require some method of breaking the charging circuit when the "kill switch" is activated. ie, a diode in the circuit to prevent damage to the regulator.  Simply opening the ground will not do this.
On our Lotus Cortina, which does not have a charging circuit, the "kill switch" was for years on the ground.  However with the recent restoration, I have put the switch adjacent to the "A" pillar on the roll cage within easy reach of the driver.  I was just "standardizing" the switch installation with our other race cars.

Rod

RE: Wiring in a Kill Switch

(OP)
I see. Thanks for the explanation.

However, in this case its purpose is not to interrupt the system whilst running, it's only to prevent the battery from draining when stored.

So, it will be fine to put it on the ground.



Thanks again!

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