Technical anyone know what this is ?

this was in my trunk on side wall of a 1934 ford ..its some kind of on/off switch that goes to a battery i think but for what ??

 

battery disconnect switch

every car should have one installed

 

^^^Yep^^^

 

not sure how it works ..you connect it to a battery with the car cables on battery also ??

 

yes battery disconnect. test with an ohm meter for open/close or you might say on/off

 

Use it to disconnect the flux capacitor.

 

Just a heavy duty 'shut off' switch that stops ANY current from your battery to go to the rest of the harness.
Like shutting off your main water valve in your house.
That way, battery charge tends to last longer.
Kinda like pulling off the negative cable from the battery, just in switch form. So no tools or contacts are disturbed.
Good to hide just for security reasons.
E

 

Disconnect the ground cable from battery. Hook said cable to this switch, after obtaining correct adapter, and connect the other side of the switch to the battery. Or some combination of that.

Ben

 

????

 

looked on web getting lots of mixed messages ..some say hook one side to ground and other to ground on battery some say hook to positive on battery and other to positive lead others say one to pos one to neg on battery ..im going with the first ..break the neg ground contact.

 

I've read that you need to use the positive post for the kill switch

 

These are required by most associations for racing. Battery disconnect. The SCTA seems to want it on the positive side of a negative ground system. You would go from the battery to the switch and from the switch to the starter solenoid.

 

Electrically it doesn't matter where in the circuit you put it, just keep the unswitched side well insulated and protected. These are handy if you don't want your car to be swiped, or if an electrical fire starts, the battery can be disconnected quickly. Also if you have to do any work on your electrical system, you can isolate it quickly.
If you have anything electronic (radio with memory, clock, etc) which needs constant power, you can connect a 1/2 amp fuse before this switch, which will keep these things working.

 

If it is going to be a kill switch (without needing other electrickery) and not just a battery disconnect it needs to be wired as in the diagram with the alternator output connected on the battery side of the switch, if the alternator is connected to the starter (or anywhere else on the load side of the switch) the motor will not cut when the kill switch is operated as the alternator will continue to power all the circuits on the car.

 

I like the ones that have the red "key" that comes out so when you switch the power to off, you can take the key with you and they can't drive off in your car.

 

The bolded will create spectacular results! DO NOT DO THIS! I would also ignore any further advice from those people.

 

Correct ^^^^^
In most motorsport regulations the battery disconnect must be on the +side of the battery [- ground]
You also run the Alternator wire to the battery side of the switch to prevent the charge feeding back to the ignition circuit.
You can also use a diode [close to the battery end] on this Alternator wire, so the charge goes towards the battery, If the Alternator wire short circuits it will not discharge.

 

Yeah, I put mine on the positive cable so absolutely nothing works with it "off". and here's why. Let's say Joe Thief wants to steal your car and you've incorporated this switch in the ground side of your system. All the bad guy needs to do is use a jumper cable to ground the battery terminal to the car....especially easy if he has easy access to your battery. Instant current!!
But lets say you've put the switch on the positive side of the system:
Now, if you've hidden the switch and the battery is in the trunk, he has to run a cable all the way from the positive side of the battery [hopefully locked in the trunk] to your starter post up front. That's a lot more work and it takes time...to much B.S. for most thieves. At least, thats' the way I see it.

 

thanks for all the replys.. its just for winter storage ..as battery is up under passenger side front fender ..all done now and work great ..dont care about thieves its insured for 2x what its worth ..
cheers

 

I just used that pic to show it off the hot post.

good point though.

Mine comes off the batt through the switch and to the starter...

 

You really should consider including a ‘battery tender’ to keep the battery charged. Batteries discharge when idle even with no cables connected. I use them on all dormant batteries, even if only for a few weeks storage. In addition to keeping the battery fully charged, it prolongs battery life.

Ray