A question about battery connection (imput please)

[Juggino]

I came across something I have never seen before and wondering if anyone knows what the purpose is. I asked my shop to install a battery cut off and they installed one of those cheap ass knob style terminals on the negative of the battery. I am not happy about any of that to begin with. Putting that aside, they also installed a standard fusable link ( just the normal 16-18 gauge wire with a 2 prong fuse). They installed this fusable link where both sides of it are connected to the main negative terminal. It does not go "inline" with anything. It simply goes from the negative terminal to the negative terminal. See attached sketch. This is a very reputable and knowledgeable shop and I not think it was a mistake. I think it has a purpose. Anyone? Please excuse the crude sketch.

[Ronnie's.930]

That fusible link is so that electricity from the battery is still available for things such as the radio and door locks (the ground from the battery is still in place, via the fuse link, but a large amp draw from the starter will pop the fuse). In other words, even when you remove the knob from the cut-off device, the low amperage accessories will still be powered.

[JJ 911SC]

A fused switch will maintain current to your alarm, on-board computer, central locking system, but still prevent your car from starting - the current generated when attempting to start the vehicle will blow the fuse and shut down all electrical connections.

[JJ 911SC]

Ronnie type faster… much faster

[Ronnie's.930]

Ha, yep, I won by three minutes!

[Esel Mann]

Call them and ask?
As you describe it, and with no further details it would appear that perhaps it was there prior and they effectively "disabled" that portion while keeping it there should you desire as others posted down the road....

[AJ's 911]

I think it lets enough juice through to keep some electronics on such as clock or radio memory even though you have removed the key/knob. 2 separate pics as examples below:

[Ronnie's.930]

You're too slow with the draw, AJ. It might be time for you to start thinking about adding a turbo!

[Juggino]

AJ, that is exactly what was installed. So then if it still lets current through it defeats the knob / cut off correct? For instance if I had a short it would still burn even after turning the knob.

[JJ 911SC]

If you want an 100% cut off (no power to alarm, clock and so on), remove the fuse

[Ronnie's.930]

Originally Posted by Juggino

AJ, that is exactly what was installed. So then if it still lets current through it defeats the knob / cut off correct? For instance if I had a short it would still burn even after turning the knob.

What is the amperage rating of the fuse (likely 3-5 amps)? A short will pop a low amperage fuse instantly.

[AJ's 911]

Originally Posted by Ronnie's.930

You're too slow with the draw, AJ. It might be time for you to start thinking about adding a turbo!

Haha, I'm big on visuals and I have seen the switch before so had to do a search.

[Juggino]

So maybe I can impose on you guys for one more bit of guidance and opinion. For some reason I have in my head that I would like to have a foolproof way to completely cut all power from the battery in case a short occurs. I realize that given normal reaction time there would be plenty that would burn quickly. However, I just think I would feel comfortable with a good solution. I guess the only real solution would be to install a regular race car type battery cut off on the positive side. I would want the switch or "key" to be inside the cockpit. That would mean installing a cut off with a cable "remote" switch correct? Also, I would have to run a 0 gauge wire to the switch then on the "out" of the switch connect my existing power wires including amp wire, and other accessory wires as well. Anybody have a good recommendation? Or its obvious and have to do as I mentioned.

[AJ's 911]

Originally Posted by Juggino

So maybe I can impose on you guys for one more bit of guidance and opinion. For some reason I have in my head that I would like to have a foolproof way to completely cut all power from the battery in case a short occurs. I realize that given normal reaction time there would be plenty that would burn quickly. However, I just think I would feel comfortable with a good solution. I guess the only real solution would be to install a regular race car type battery cut off on the positive side. I would want the switch or "key" to be inside the cockpit. That would mean installing a cut off with a cable "remote" switch correct? Also, I would have to run a 0 gauge wire to the switch then on the "out" of the switch connect my existing power wires including amp wire, and other accessory wires as well. Anybody have a good recommendation? Or its obvious and have to do as I mentioned.

Lots of threads on protecting your electrical circuitry with adding inline fuses and relays. The battery kill switch is more of a theft deterrent. If you want a true kill switch (cutting off all power) then I think you have a pretty good idea. Illustrations below:



Also take a look at this website: How to Install a Race Car Emergency Kill Switch

[mpetry]

Beware those green knob battery cut-offs. They are caca. Years ago when they were made by "Moroso" - pretty good. Current version spewed out by low cost production facility who knows where - NtWrthSht.

The Hella cutoff switch is a great part and can be had on Eboy with cables for beer money.

[Juggino]

Yes, i just need to also include a tap for the gadgets. I guess I will use 2 terminal blocks, one that will go right after the kill switch that will give me 2) 4 gauge leads. One for the power amp and one that I will take into a fuse block that will then split the 4 gauge wire into 3-4 new fused 16 gauge feeds for the other stuff, radar, USB charging ports, etc.

I guess my reservation is that I have to install one of those "remote" cable pull switches.

[Juggino]

Yes, I too had a bad experience with one of those knob type cheap ass cut offs. It went bad in a friends car and we were stuck pretty far away. The car had zero power, funny, switched the battery, tried everything. Went crazy troubleshooting. Finally figured out it was that dam thing.

[Juggino]

Additional stuff added

[Juggino]