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Help with relay wiring!

Posted: Thu Apr 23, 2009 4:35 pm
by supernova
This is what I've come up with can i get some help here? Is this good for the switch in and out of the car?

Re: Help with relay wiring!

Posted: Thu Apr 23, 2009 9:02 pm
by John_Heard
That setup will work.

I did mine differently when I had an alternator so I didn't have to use the relay. Don't have a wiring diagram of it right now though but it used two main hot wires, one up to the starter and alternator were hot all the time, and the on/off kill switch feed everything else through a seperate heavy cable.

Re: Help with relay wiring!

Posted: Thu Apr 23, 2009 11:27 pm
by chpcamaro
hey chris does your solenoid use 12v to activate mine uses a ground so the switch takes the ground away and it shuts the solenoid down. and is it a continous duty solenoid?


the top picture is with a ground switch instead of 12v switch click on them and you can see them better

Re: Help with relay wiring!

Posted: Fri Apr 24, 2009 9:06 am
by supernova
Hi Rob,
This one uses 12v to activate. Your 2nd pic I think would be the right one.

You did make my hand drawing look like a 1st grader did it with your fancy ass CAD stuff. :nutkick:
I guess that's what I get for being a 1st grader! :lol: :lol: :lol: :lol: :lol: :lol: :lol:

Re: Help with relay wiring!

Posted: Fri Apr 24, 2009 9:36 am
by John_Heard
Been goofing off doing some drawing myself - this is the main stuff for in the trunk, but I haven't got around to adding wire numbers, colors, etc. yet.

Re: Help with relay wiring!

Posted: Fri Apr 24, 2009 2:02 pm
by chpcamaro
thanks john your detailed drawing makes me feel like a second grader now

Re: Help with relay wiring!

Posted: Fri Apr 24, 2009 2:24 pm
by John_Heard
LOL - I used to do that stuff for a living many moons ago. I sure miss Autocad.. That was done using a freebie program called Inkscape

Re: Help with relay wiring!

Posted: Sat Apr 25, 2009 11:03 am
by supernova
Thanks guy's for the help. Oh and thanks for not making fun of my grade school drawing. :smt003 :smt003

Re: Help with relay wiring!

Posted: Mon Apr 27, 2009 11:54 am
by Dykes&Strippers
supernova wrote:This is what I've come up with can i get some help here? Is this good for the switch in and out of the car?
Though this set-up will work as far as powering everything, it would not pass tech the way the alternator is wired...essentially it is wired to the wrong side of the main kill switch. For it to effectively work it needs to tie directly to the battery, but then that raises the question of being able to isolate the alternator wire from the battery in the event of a mishap. The only safe way to do it is to buy a 4 post kill switch (made for an alternator), or as some do, put a constant duty solenoid in line with the alternator.

Hope this helps...

Re: Help with relay wiring!

Posted: Mon Apr 27, 2009 12:21 pm
by Dykes&Strippers
Looking at everyones drawings, minus John's, I see some potential failure points that are not necessary. Everyone seems to want to put a solenoid in line of the MSD ignitions with their ign switch controlling this...Generally, we starting using these as a remote solenoid for the starter, and a greta place to tap for MSD power etc. The way the diagrams posted here are, they are not used for the starter but simply a power point for the rest of the car. That solenoid is a potential mechanical failure point. The simplest and cleanest way would be to use a through the fire wall connector...run your cable from the battery through the kill switch to that connector. From that connector you can now jump down to the starter. On the inside, you have a clean place to grab switch panel power as well as MSD power or anythig requiring battery power. This does several things..reduces the amount of wire, reduces a potential failed part, ensures you have propper current carrying capability to all accessories (at leaste 2 Ga), and gives you power both inside and out of the drivers/engine compartment.

Another point to add...in all cases where weight is not a factor, I also put a second through the firewall connector in and use this as a dedicated grounding point...also using at leaste a 2ga cable directly from the battery...eliminating the inconsistencies of grounding through the chassis.

I hope this does not offend anyone or stir up any arguments...just sharing some info and results we have picked up along the way. Hope to be of some help! :thumb:

Re: Help with relay wiring!

Posted: Tue Apr 28, 2009 6:48 pm
by bracketracer
I have not seen a cut off switch that will handle a load from an alt...Maybe some one can post one??? I used a sol from here....Works great and the tech guys like it..

Re: Help with relay wiring!

Posted: Tue Apr 28, 2009 6:50 pm
by bracketracer
I have not seen a cut off switch that will handle a load from an alt...Maybe some one can post one??? I used a sol from here....Works great and the tech guys like it..

www.texasindustrialelectric.com/relays.asp[/img]

Re: Help with relay wiring!

Posted: Tue Apr 28, 2009 7:38 pm
by supernova
Dykes&Strippers wrote:Looking at everyones drawings, minus John's, I see some potential failure points that are not necessary. Everyone seems to want to put a solenoid in line of the MSD ignitions with their ign switch controlling this...Generally, we starting using these as a remote solenoid for the starter, and a greta place to tap for MSD power etc. The way the diagrams posted here are, they are not used for the starter but simply a power point for the rest of the car. That solenoid is a potential mechanical failure point. The simplest and cleanest way would be to use a through the fire wall connector...run your cable from the battery through the kill switch to that connector. From that connector you can now jump down to the starter. On the inside, you have a clean place to grab switch panel power as well as MSD power or anythig requiring battery power. This does several things..reduces the amount of wire, reduces a potential failed part, ensures you have propper current carrying capability to all accessories (at leaste 2 Ga), and gives you power both inside and out of the drivers/engine compartment.

Another point to add...in all cases where weight is not a factor, I also put a second through the firewall connector in and use this as a dedicated grounding point...also using at leaste a 2ga cable directly from the battery...eliminating the inconsistencies of grounding through the chassis.

I hope this does not offend anyone or stir up any arguments...just sharing some info and results we have picked up along the way. Hope to be of some help! :thumb:

You mean like this?

Re: Help with relay wiring!

Posted: Tue Apr 28, 2009 7:40 pm
by supernova
bracketracer wrote:I have not seen a cut off switch that will handle a load from an alt...Maybe some one can post one??? I used a sol from here....Works great and the tech guys like it..

http://www.texasindustrialelectric.com/relays.asp[/img]


Like this one!!

12 Volt Continuous Duty
Special Applications: USED AS BATTERY
DISCONNECT SWITCH AND FOR EXTRA HEAVY DUTY ELECTRICAL LOADS.
USED IN MANY EMERGENCY VEHICLES APPLICATIONS LIKE,AMBULANCES,FIRE TRUCKS .
Amps: 225
Coil Type: Isolated
Coil Volts DC: 12 DC
Contact Form: SPNO
Contact Material: Copper
Duty Cycle: Continuous

Re: Help with relay wiring!

Posted: Tue Apr 28, 2009 10:38 pm
by Dykes&Strippers
bracketracer wrote:I have not seen a cut off switch that will handle a load from an alt...Maybe some one can post one??? I used a sol from here....Works great and the tech guys like it..
Cole Hersee part number 75912... go to colehersee.com. The best thing is to call their customer service center, give them your zip code and they will tell you who in your area sells their products!!! Thisis a true cut off switch...not a solenoid...rated for 175 amps continuous and 750 for 15sec.