Best place to get 12v switched...

[Greg_B]

I am going to add a six circuit fused distibution panel under my dash for all the accessories like CB, Stereo, lights, etc.

I would like to have a relay that powers this panel so it only has power when the switch is in the on or acc position.

Where would be the best place to make this connection? What size relay should I use? Is 40amp enough or should I go bigger?

Anything else I need to take into account?

Greg

 

[hotrodtim68]

Adding the extra circut.

Try giving Painless Wiring tech a call; they can be very helpfull.

 

[Viperwolf1]

If you're going to pull 40 extra amps to the interior it's best to run a new 10 ga wire (with fusible link) from the starter solenoid/battery. You can control it with a relay triggered from the back of the ignition switch. The stock interior main power distribution wire was marginal with no accessories.

 

[00gyrhed]

the ignition switch is probably only rated for 30A. I recently wired all my switched power through relays, my ignition switch does nothing but fire a big pile of relays.

 

[Greg_B]

If you're going to pull 40 extra amps to the interior it's best to run a new 10 ga wire (with fusible link) from the starter solenoid/battery. You can control it with a relay triggered from the back of the ignition switch. The stock interior main power distribution wire was marginal with no accessories.

Yes this is what I plan to do... I know I will need to run a wire from the starter relay... I just was not sure where to pull a "signal" wire from that would allow 12V in both acc and on position.

Greg

 

[Viperwolf1]

Yes this is what I plan to do... I know I will need to run a wire from the starter relay... I just was not sure where to pull a "signal" wire from that would allow 12V in both acc and on position.

Greg

Use the stud terminal on the back of the ignition switch.

 

[Greg_B]

I thought the stud had power all the time... even with the switch off...

I need to buy a new meter...

Greg

 

[Viperwolf1]

I thought the stud had power all the time... even with the switch off...

I need to buy a new meter...

Greg

Negative. The only terminal that is always hot is the one with the thick yellow wire.

 

[Greg_B]

You are the man...

Greg

 

[Explorer]

Plan for a constant hot wire for a modern stereo, or you'll be resetting the clock and presets.

 

[gumbydood]

I recently added a stereo and some 12v outlets in my 71. I got a console from Wild Horses for the deck. It has an ipod input, so I drilled a hole from the stereo port to the main storage box. I wanted to be able to run the deck with the key in acc and on, but I also wanted to be able to run the deck with the key off and not backfeed the ignition system. I pulled an 8ga. fused (40amp) wire from the solenoid to a distribution block on the tranny tunnel. I ran a wire from the dist. block to the yellow (batt+) deck wire, then ran a pair of wires from the red (12V switched) deck wire... 1 to the dist block via a switch inside the main storage box and 1 to a relay behind the dash. I ran a power wire from the dist. block to the relay and a ground to the mounting screw. I picked the switched power from the back side of the fuse panel (there are several male spade terminals on the back of the fuse panel that I used one of). This closes the "normally open" relay to power the deck with the key.
I also used the distribution block to run power for a 12v power outlet inside the main storage box and a trio of them on the dashboard.
Good luck
G'dood