Cascade Crew

Twilightoptics

So here are the MOROSO instructions. If I understand this right... It says run a jumper from the alternator output to one of the switch terminals.

Are they saying to disconnect the current output wire and run new to the switch, or just run one over the top of the old one (which still would be connected to the battery?) I guess it doesn't make sense... but I'm trying to figure out why it would only say max 20amps? I mean.... our factory alternators put out more than that?!

I orderd the painless wiring alternator shutdown kit... which I'm sure would be enough to work the alternator, but if I can get the 4 post switch to work I'd like to do that... but 20 amps?

http://www.moroso.com/catalog/categorydisplay.asp?catcode=42225
Click instructions for 74102

scott in wa. · Posted: Fri Oct 27, 2006 6:59 am Post subject: cut off

main shut off?
why is the alternator involved?

izcain · Posted: Fri Oct 27, 2006 7:21 am Post subject:

I just ran a wire directly to the battery and called it a day. I didn't even need to have the painless wiring kit. Of course I have Full msd so when I shut the disconnect off it kill the box and the engine dies no matter what. I was having the same trouble you were. Hope this helps some.

Twilightoptics · Posted: Fri Oct 27, 2006 11:36 am Post subject:

Scott my undetsanding is that the alternator can cause current to still flow to the ignition even after the battery is disco.

I'll be doing that. Running all my power to car off the starter, and the output from the alternator back to the battery side of the switch.

Team chevelle verified. Thanks Izcain :O)

I hoped to not need the painless kit.

izcain · Posted: Fri Oct 27, 2006 4:51 pm Post subject:

I doubt you will need the painless kit if you wire the alternator right to the battery.

QwkTrip · Posted: Fri Oct 27, 2006 8:40 pm Post subject:

What is it that you want to accomplish? A disconnect switch is wired in series with the electrical device(s) that you want to isolate. That will dictate where you splice it into your electrical system. Which switch do you have? The Super Duty switch or the battery disconnect switch?

It appears from the website link that the Super Duty switch is meant to be in-line with the battery post negative cable as a disconnect switch for the entire electrical system. Basically, a way to disconnect all electrical devices so you don't drain down the battery when the car is parked. Although, if you want to use it as an emergency shutdown device then you'll have to disconnect both the battery and alternator on the high voltage side to cut all voltage sources from the car.

The battery disconnect switch is rated at 20 A continous duty and is intended only to disconnect a specific electrical device, such as a fuel pump or ignition system. The name is misleading as you would never use it to disconnect the battery from the rest of the car.

As far as the alternator goes, yes it powers everything while the car is running and the battery doesn't do a thing. The only purpose for the battery is to provide standby power when the engine is off and to crank the starting motor. The battery and alternator are connected. So if the alternator quits charging (or is disconnected) then the battery will provide power until it is completely discharged.

It is not a good idea to disconnect the battery and leave the alternator powering the car. The battery acts like a damping device and swamps voltage spikes that could otherwise damage other electronic devices on the car.

QwkTrip · Posted: Fri Oct 27, 2006 9:38 pm Post subject:

Ah, I get it now.... I saw your other post about moving the battery to the back of the car. You want an emergency shut down switch.

What are the club requirements for the type of racing you plan to do? Do you need to cut all voltage sources from the car, or just cut off the fuel pump?

Dewey316 · Posted: Sat Oct 28, 2006 6:42 am Post subject:

It should cut all voltage to the car, and IIRC the rules state, the car must shut off with the switch.

blue89 · Posted: Fri Nov 03, 2006 4:01 pm Post subject:

Sounds like you would have to run your alternator power back to the battery, or add the switch downstream of the starter distribution after you run the battery and the alternator to the starter posts.

Or you could power a relay, but that would only work if the switch had an auxilary output.

Is there a location requirement for the switch?

Twilightoptics · Posted: Fri Nov 03, 2006 6:49 pm Post subject:

Yep. Has to be in the back and easily accessable and labeled.

Got it taken car of thanks to TC and Izcain