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FIA TYPE SWITCH WIRING
richard - 28/5/11 at 10:22 PM

Sorry if this is a silly question but here goes.
I want to fit an FIA Type switch that i have already bought to the dash board my already road legal book chassis locost not as an anti theft devise but just to make it easy to cut the power in the event of a accident / fire type / emergency.
At present the alternator lead goes to the battery along with the main lead to the starter motor.

i was gong to run the alternator lead to the stater motor permanent live connection and then run the main lead from battery to cut out switch and then the other side of the switch to the main terminal on the stater motor where the alternator lead is.

But i am aware that although it is not good practice you can disconnect a battery and allow the atternator to run the car, so not sure if this is the correct way to wire it or not.
cheers Richard.

designer - 28/5/11 at 10:30 PM

On this page:

http://www.shedworks.eu/tips.html

Chippy - 28/5/11 at 10:33 PM

The way that I did mine was to break the earth lead, which I was told would not ruin the alternator if the engine was running when I flipped the cut out. Have no idea if it's true as never had to shut down with the engine running, :-) Cheers Ray

BaileyPerformance - 28/5/11 at 10:39 PM

quote:
Originally posted by richard
Sorry if this is a silly question but here goes.
I want to fit an FIA Type switch that i have already bought to the dash board my already road legal book chassis locost not as an anti theft devise but just to make it easy to cut the power in the event of a accident / fire type / emergency.
At present the alternator lead goes to the battery along with the main lead to the starter motor.

i was gong to run the alternator lead to the stater motor permanent live connection and then run the main lead from battery to cut out switch and then the other side of the switch to the main terminal on the stater motor where the alternator lead is.

But i am aware that although it is not good practice you can disconnect a battery and allow the atternator to run the car, so not sure if this is the correct way to wire it or not.
cheers Richard.

Hi,
The switch has 2 contacts as well as the main battery contact. Run the red alternator wire to the starter as normal.
The main (big) contacts break the main heavy red cable from the starter to the battery, as you said.
The normally open contact should be used to disconnect the ECU/Coil (to stop the engine if the isolator is operated with engine running). The second normally closed contact should be wired from the engine side of the main battery isolator contact via a 3ohm resistor to ground. this "drains" the alternator power down to ground when the isolator is operated and the battery is disconnected. This protects the car from electrical surge damage and protects the alternator regulator from over voltage.
You should have been supplied with the resistor when you bought the isolator.

HowardB - 29/5/11 at 06:46 AM

quote:
Originally posted by designer
On this page:

http://www.shedworks.eu/tips.html


a page full of useful stuff,....

thanks