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Hoodooman 12-24-2024 09:12 AM

Positive ground battery disconnect switch?
 

Hi everyone, New 52 customline owner. I'm having difficulty finding a battery disconnect switch to fit my positive side top post battery. This is my first positive ground vehicle. The positive post is a bit larger than the negative. Does anyone have a recommendation for a battery disconnect that will fit?

Thank you for any help!

19Fordy 12-24-2024 09:21 AM

Re: Positive ground battery disconnect switch?
 

3 Attachment(s)
I have been using one of these on the (+) terminal for the last 40 years. They are not made of brass.
Car is 40 Ford converted to 12V, Negative ground.
It will also OEM 6V battery.
https://www.ebay.com/itm/14527938600...b1bc988a46e8e6

and this:

https://www.bing.com/search?q=what+t...ANAB01&PC=HCTS

51504bat 12-24-2024 09:27 AM

Re: Positive ground battery disconnect switch?
 

English cars used to have a positive post mount disconnect switch. Lucas made IRRC. Hard to find and pricey but a really nice set up.

Drbrown 12-24-2024 10:06 AM

Re: Positive ground battery disconnect switch?
 

An option would be to install a battery safety/security switch. I have 12 volt neg ground. The switch I installed fit right thru a punch-out hole in the fire wall. The on-off knob is inside the car and easily reached from driver's seat. Being inside car provides some security and reachable during emergency i.e. accident. Best thing _ saves opening and closing car hood every time you use the car. Ran Positive cable from batt to switch terminal on engine side of firewall, then from switch to starter solenoid. I can provide info of where I bought the switch from and photos too.

Tim Ayers 12-24-2024 10:17 AM

Re: Positive ground battery disconnect switch?
 

Quote:

Originally Posted by Drbrown (Post 2357940)
An option would be to install a battery safety/security switch. I have 12 volt neg ground. The switch I installed fit right thru a punch-out hole in the fire wall. The on-off knob is inside the car and easily reached from driver's seat. Being inside car provides some security and reachable during emergency i.e. accident. Best thing _ saves opening and closing car hood every time you use the car. Ran Positive cable from batt to switch terminal on engine side of firewall, then from switch to starter solenoid. I can provide info of where I bought the switch from and photos too.

I have the same. These type of switches can be used from 6V-36V systems. Cole-Hersee makes a really good one.

https://www.elecdirect.com/cole-hers...le-pole-off-on

If you order one, get it from Rick @ Noble Speed. He is a great small business who offers some really neat parts. Please support him

https://www.noblespeedequipment.com/...er-kill-switch

glennpm 12-24-2024 11:25 AM

Re: Positive ground battery disconnect switch?
 

Quote:

Originally Posted by Hoodooman (Post 2357925)
Hi everyone, New 52 customline owner. I'm having difficulty finding a battery disconnect switch to fit my positive side top post battery. This is my first positive ground vehicle. The positive post is a bit larger than the negative. Does anyone have a recommendation for a battery disconnect that will fit?

Thank you for any help!


As long as EITHER post is isloated, the battery will be disconnected.
Put your switch on the other smaller post.

Hoodooman 12-24-2024 02:39 PM

Re: Positive ground battery disconnect switch?
 

Thanks everyone. From what I've seen, every connector has a .6X size ID which is only good for the negative terminal. I'll keep looking. Thanks for the input, much appreciated!

JayChicago 12-24-2024 04:59 PM

Re: Positive ground battery disconnect switch?
 

Quote:

Originally Posted by Hoodooman (Post 2358004)
Thanks everyone. From what I've seen, every connector has a .6X size ID which is only good for the negative terminal. I'll keep looking.

Don’t see why having the disconnect on the “hot” terminal rather than on the ground terminal will make a difference.

Hoodooman 12-24-2024 06:36 PM

Re: Positive ground battery disconnect switch?
 

Thanks, I'd love to see a pic if your firewall switch setup.

52flthed 12-24-2024 07:37 PM

Re: Positive ground battery disconnect switch?
 

2 Attachment(s)
On my 52 truck. We installed a Cole hearse marine grade switch mounted on or in one of the battery supports. Coming off the negative side in between the solenoid. So neg battery cable goes down to switch and comes back up to solenoid it looks to casual observer that it’s the same cable.

paul2748 12-24-2024 10:02 PM

Re: Positive ground battery disconnect switch?
 

When I want to disconnect my battery, I just remove the ground cable (positive in your case) from the battery using a 1/2 inch wrench. No muss, no fuss, and costs nothing. Since the battery is in plain view, this is the best and cheapest solution. No wear and tear either

tubman 12-24-2024 10:04 PM

Re: Positive ground battery disconnect switch?
 

Plus, it gives you the opportunity to quickly clean the terminal with one of those nifty two-piece brushes.:)

1948F-1Pickup 12-25-2024 04:08 AM

Re: Positive ground battery disconnect switch?
 

Quote:

Originally Posted by JayChicago (Post 2358028)
Don’t see why having the disconnect on the “hot” terminal rather than on the ground terminal will make a difference.

It only matters to sanctioning bodies like the NHRA.
They always say it should be on the positive side and should stop all electrical functions.
Their reasoning is, if the switch is on the negative side of the battery, the alternator is not being interrupted and could still generate power and cause issues, since it is still capable of generating power in the electrical system.
(Back feed of the ignition)

51504bat 12-25-2024 09:20 AM

Re: Positive ground battery disconnect switch?
 

Quote:

Originally Posted by 1948F-1Pickup (Post 2358100)
It only matters to sanctioning bodies like the NHRA.
They always say it should be on the positive side and should stop all electrical functions.
Their reasoning is, if the switch is on the negative side of the battery, the alternator is not being interrupted and could still generate power and cause issues, since it is still capable of generating power in the electrical system.
(Back feed of the ignition)


I understand the NHRA position but on my daily driver my disconnect switch breaks the ground. The reason being that with the ground disconnected if something happens to touch the hot post to the frame nothing will happen. If you break the hot lead as per the NHRA and somehow there is a connection between the hot post on the battery and a ground source then sparky sparky. JMO

glennpm 12-25-2024 09:57 AM

Re: Positive ground battery disconnect switch?
 

Making the simple complicated for over 30 years. :D

paul2748 12-25-2024 03:41 PM

Re: Positive ground battery disconnect switch?
 

Totally agree


Quote:

Originally Posted by 51504bat (Post 2358112)
I understand the NHRA position but on my daily driver my disconnect switch breaks the ground. The reason being that with the ground disconnected if something happens to touch the hot post to the frame nothing will happen. If you break the hot lead as per the NHRA and somehow there is a connection between the hot post on the battery and a ground source then sparky sparky. JMO


corvette8n 12-26-2024 09:06 AM

Re: Positive ground battery disconnect switch?
 

https://www.fordbarn.com/forum/showt...Cole&showall=1
Read through these posts.

pistonbroke 12-26-2024 09:42 AM

Re: Positive ground battery disconnect switch?
 

Way back in the early days of my automotive training we were always told to disconect the ground first no matter which polarity you were working with. I've seen batteries explode and wrenches welded to the vehicle by not following this simple rule. Tim

kiwi nz 12-26-2024 04:30 PM

Re: Positive ground battery disconnect switch?
 

Quote:

Originally Posted by pistonbroke (Post 2358248)
Way back in the early days of my automotive training we were always told to disconect the ground first no matter which polarity you were working with. I've seen batteries explode and wrenches welded to the vehicle by not following this simple rule. Tim

Me too, and, I have had the “sparky, sparkies” when I have forgotten.

itslow 12-26-2024 04:52 PM

Re: Positive ground battery disconnect switch?
 

Positive or Negative it doesn't really matter in the grand scheme of things; they both produce the same result. Use whichever you're able to obtain and install.

If you're using a disconnect switch and running *all* your power through it, pay attention to both the constant and intermittent current ratings. The Cole-Hersee posted earlier has a relatively low current rating (20A continuous, 125A intermittent). If you have upgraded to a later generator that's capable of outputting >20A you will exceed that switch's rating. Cranking current is also something that should be considered if using the switch in your starting circuit.


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