Main Battery Disconnect switch location?

[Carl Johansson]

Rule 3.K calls for:
All vehicles must be equipped with a main battery disconnect switch.  The disconnect switch must be visible and clearly marked.

I was getting ready to mount the switch on the outside of the car -  but I don't particularly like drilling big holes in the plastic.

Can it be mounted on the instrument panel inside the car?  while I see the benefit of having it outside the car -  i could see where it would have some value for a driver to be able to shut down the power in an emergency!

i guess this hinges on the definition of visible.

Carl Johansson

[Harold Bettes]

Carl,
You need the shutoff outside and clearly marked so that the folks can shut off all electrical if you are out cold or on your head!

IF you want to have a main disconnect in the cockpit also, do it just like a panic switch in parallel with the main external to the vehicle. However remember the fewer moving parts the better.

Regards to All,
HB2

[Stainless1]

Especially electrical parts used on the salt.  The idea is an emergency shutoff for the rescue guys or if you are on fire at the starting line.  Recommended spot in on the back of the car.  Hey, it's just a half inch or so hole... 

[Carl Johansson]

Carl,
You need the shutoff outside and clearly marked so that the folks can shut off all electrical if you are out cold or on your head!

IF you want to have a main disconnect in the cockpit also, do it just like a panic switch in parallel with the main external to the vehicle. However remember the fewer moving parts the better.

Regards to All,
HB2

Harold -  you may be right -  but I'm arguing that in a rollover situation a switch inside the roll cage would have a far better chance of being in tact than one on the exterior of the car -  of course I guess you could argue if the switch gets destroyed it would probably have fullfilled it's duty.

Once again I am flambuzulated by lack of clarity in the rule book!

[hitz]

 Carl,
  I've been looking at the same problem for a while. It would be best if the battery could be shut down outside or inside.
  There is a switch in the Summit catalog  #PRF 30305 that comes with a remote switch (solenoid) and a panic button. It should be easy to run another switch (and diode) that would allow the shut down to operate from two locations. My problem is, it has only the battery shut down and no alternator or magneto shut down terminals. Maybe that wouldn't affect your application. I am going to probably run a alternator. So problem here is not solved yet.   I would prefer to not run any main battery cables into the cockpit.

  Harvey

[JackD]

The object of the required main electrical disconnect is to allow the emergency crew to operate it from out side the vehicle.
The best location is across the rear because regardless how the vehicle stops, you can be pretty sure it will not be on it's tail.
Front ends get really wrecky and are not a good choice.
You don't have to drill a hole in the body or even get to the handle on the switch.
Make a bracket that can be fastened adjacent to the chute or mount it inside with a pull rod through an existing place like the licence plate area.
It is not the end of the world and you don't have to deface the car. 

[Mile High Talon]

I have a trunk-mount battery because of limited room underhood which required an ext. cut-off switch for NHRA competition, and took the advice on the NHRA website and bought an extra tail-light and mounted the cut-off switch inside the tail light housing. No hole to cut through the sheet-metal and easy to remove the switch and attached cables if you want to run on the street or sell the car. I also used 0 ga. cables due to the distance to and from the engine bay and alternator on my set-up and a sealed battery box.

My tail light cut-off switch set-up required placing a piece of 20Ga. sheetmetal on the inside of the tail light plastic lens for the switch to mount through to reinforce the lens plus a switch-plate on the outside. This set-up on my car has passed NHRA, SCCA, & most-recently USFRA tech. Jeg's sells a switch for ~$17 (p/n 555-10305) that I bought. You can also get the Jeg's switch (p/n 555-10373 300A $85 or 555-10372 125A $63) that mounts through the trunk floor with a rod that goes back through a bracket which attaches to the lower edge of the rear bumper or valance if you don't have a tail light/fender design that would allow a switch to be placed inside it.

If you also want an interior kill switch you can get the Flaming River switch from Jeg's for $80 (p/n 898-FR1013).

[BTW- Jeg's gave me a small discount and some free shirts and hats last season for running their decals on my car at WoS and promoting them on the web.]

I have pics of every step of the TMB install & tail light conversion for the cut-off switch available to anyone interested if you e-mail me.

James

[JackD]

I think Mile high  gets it.

[Seldom Seen Slim]

Mr. HB2, Sir.

Don't put that extra switch in PARALLEL with the other one, put it in SERIES!

[JackD]

Mr. HB2, Sir.

Don't put that extra switch in PARALLEL with the other one, put it in SERIES!

I think Mile High gets that too.
What he wants to also get is the cable from a welding supply instead of an Auto Parts store, it is way cheaper and they have all the suitable connectors.

[Harold Bettes]

Slim, et al,

Thanks for the correction. What I meant to say was in conjuction with an interior switch, I did not mean the electrical parallel. Poor choice of description on my part.

So much for placing the fingers in gear before the thought clutch was used!

Regards to All,
HB2

[JackD]

I always say that I did those little errors to see if they are reading carefully.
Sometimes it works and other times is is just an error.

NOTE TO SSS:
Howami doong on my pluncttuaion?

[1212FBGS]

just don't buy that cheep black plastic switch with the red lever. get a good one... you wont be sorry
kent

[jimmy six]

Carl you did not say what kind of vehicle you are using but during inspection I have seen many applications of the rule. The most innovative was inside the normal gasoline filler tank flap. The most important thing is the writing of it's location and whether you push or pull it. One person did it right side up and upside down. Quite clever.

Since the NHRA uses the rear and many batteries are in the trunk area it is a common place. Many roadsters have it in the area in front of the engine and have the lever on the side of the hood. Others have the lever in the open cockpit area with marking showing where it is. (arrow works)

I personally do not like it inside a coupe where you need to get inside. Even with a identifying tag being upside down and not being able to open a door with an electric fuel pump running causes panic. When rescue personnel reach your car they want to be able to shut stuff off. Many do not know the difference between an electric water pump or fuel pump.

Good luck.

[Seldom Seen Slim]

Unh, Jack, maybe you should go back and check this:  "...Auto Parts store, it is way..."

You should have substituted a period for the comma, then double-spaced and started the new sentence with a capital "I".

But since you asked -- you get a couple of points for admitting you weren't sure, and only one point removed for making the mistake.