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Discussion Starter · #1 ·
Hi Guys, I want to reuse my original pop ignition barrel, with the outer ring which operates the lights. Originally though it would of been 6v, and positively earthed, right? The "batt", "ground", "side" and "head" terminals are clearly stamped on the back, but I want to check the wiring before starting to wire it it. Can someone please confirm for me the wiring for negative earth (12v).

Thanks guys!
Mark
 

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Just follow the instructions on the switch, it won't know that the power is flowing 'backwards' to what it is used to.:incheek::tup: I don't knwo if teh switch will be man enough, especially if you uprate headlamp outputs and may be best to use teh dash switch to operate relays to take the load off the switch itself.

The only thing that causes problems when switching over pos to neg is the radio and the coil terminals need switching ( is using original coil ). The lead to distributor should always be the same as whatever the cars earth terminal is.
 

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Discussion Starter · #3 ·
Thanks very much. Can you explain the reason for your suggestion about using relays for the lights please? I'd rather look stupid now by asking than stupid when my car is a pile of ash ;-)
 

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Switches are rated at various amperages and reflect the amount of current it can handle without starting to melt under the load. Relays are simply switches operated by electric rather than manually.

By using a relay all the heavy load passes through the realy ( which are usually rated at 30 amps ) and all the old light switch does is turn the relay on so very low loading and won't burn it out.

No worries from me about asking questions, stupid or not, no one was born knowing any of this and you only find out by asking. Everyone should remeber how little they once knew , or still do, before belittling others who do ask.
 

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Discussion Starter · #5 ·
Thanks Kev, I understand. I don't claim to be an expert, just willing to learn. With wiring there is a definite right or wrong answer, and I don't want to get it wrong. Thanks again.
 

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"call 0-800 Apocalypse"
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Switches are rated at various amperages and reflect the amount of current it can handle without starting to melt under the load. Relays are simply switches operated by electric rather than manually.

By using a relay all the heavy load passes through the realy ( which are usually rated at 30 amps ) and all the old light switch does is turn the relay on so very low loading and won't burn it out.

No worries from me about asking questions, stupid or not, no one was born knowing any of this and you only find out by asking. Everyone should remeber how little they once knew , or still do, before belittling others who do ask.
as allways very well put sir:tup: you have a way of conveying the infomation that i wish i had,long may it be:tup::twisted::tup:
 

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Fruit & Nut Case
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Following Ohms law, by doubling the voltage you are halving the current. There will be no problem with the additional voltage, its the current that can cause the damage but in this case it will be less. There will also be no problem with reversing the polarity so you should be ok
HOWEVER, expanding on what Kev mentioned you are using a 40+ year old switch and a relay for the headlight circuit would be the way to go.
 

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Discussion Starter · #8 ·
Point taken about the possibility of frying the ignition switch, now I worried :-/ . I have looked into wiring the head & sidelights (which are operated via the outer ring of the ignition switch) through relays, and I am not confident that I have it straight in my head. I figured that the relay would go between the 12v feed and the switch to protect it, but from what I gather I will need to run the head & sides through individual relays on the output side of the switch. Correct?
 

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I'm Not Jed Clampett
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the relay(s) go on the output side of the switch. You only really need a relay for the headlights, the side and tail lights take very little current.

The headlight output from the switch goes to one side of the relay coil, the other side of the relay coil is connected to your car's ground. One contact of your relay is connected to the positive from your battery via at least a 20A fuse, the other contact is wired through to your headlights via the dip switch.

HTH, Stuart.
 

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Discussion Starter · #11 ·
Fantastic! Thanks very much. I just popped out at lunchtime and got my relays. I understand now, thanks again for your help guys.
 

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78 Bronco BRING IT ON!
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Re: worth a thousand words?

Just to add that the terminal no.`s on the bottom of the relay are the same on all basic relays.The wiring diagram that`s been put up is exactly what would be on the back of the packaging a new relay from Halfords would have except it would say accessory instead of dip switch, and accessory switch instead of headlight switch.You can get loads of relays from the scrap yards out of motors once you`ve got they hang of identifying what each terminal is for! If in doubt draw it out!
 

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Discussion Starter · #13 ·
That's what I've done now-it's drawn up ready for me to tape to my dash later on. Once I had the wiring layout from the packaging it was clear. Cheers paddy
 
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