richbopp

I did a search but can't find what I'm looking for; but I remember a thread about battery disconnect switches being discussed and which side (positive or negative) to install them on.

Before I do this simple little job on the 64 I'd appreciate any opinions and reason's why to install on + or - side of battery.

Thanks, Rich

64muscl

Mine is on the negative post on my 64.

Plasticman

Either side will effectively disconnect the battery. But some of the switches will only fit over one of the terminals due to terminal diameter differences on the OEM top post mount type battery.

On side mount screw thread terminals, your choice. Have done it on either terminal, depending on location / access.

If you are a "house" electrician, only switch the "positive" (hot) side of any circuit, and this is normally good practice on a vehicle as well (most vehicle components, such as blowers, lights, etc. are switched on the positive side of the circuit). But it really does not matter for the battery disconnect.

Just thank GOD that there is not a UL for vehicles. They do great things for safety, but have gone way overboard in some areas trying to justify their existence.

Plasticman

Kensmith

Rich,

I switched mine to the - (negative) side after reading that post some time ago. Can't remember why but there were some good reasons.

Cobra66

Mine's been on the negative terminal for over two years now with no complaints.

62Jeff

I always disconnect the negative side first. The rationale being that if I were to use a tool to disconnect the positive battery cable, I want to make darned sure that if my wrench contacts metal somewhere while doing that, I don't want to short out the circuit.

So, I have my battery disconnect switches on the negative post for all of my cars.

JohnZ

The diameter of the clamp section on top-post switches is designed to go on the negative terminal post, with the same rationale as the factory shop manual, which always advises to disconnect the negative cable when working on the electrical system - that removes ALL ground potential from the car, which makes it impossible to create a short circuit, even if you drop a wrench and it contacts the positive terminal and the exhaust manifold at the same time.

Kensmith

See....I knew there was a good reason.

Paul L

Negative side for me.

richbopp

OK, the negatives have it.

Thanks for the advise and it now makes perfect sense why negative is the best.

hpexpatriot

Amen! Any organization that has a chance to throw its own weight around in defense of "Safety" "Clean Air" "Clean Water" or Clean / Safe "Whatever" can get that way over board complex.

Right now we are drying up here in Atlanta and the Endangered Species Police are debating if lowering the water flowing to Florida From Atlanta is gonna hurt some Sturgeon and some muscles that live in Florida. What happened to people first???????

These agencies like EPA and UL and Consumer Reports or one of my altime favorites Consumers Union all have their own agenda..... SURVIVAL! Of the four listed only the EPA has the benefit of assured survival as a result of an act of Congress.

Mr D.

Aviation rule #1 - when installing a battery attach the Neg lead first than the Pos lead. Same logic would work for a disconnect.

piper

piper

Did you find your electrical problem?

1-2-b-67L89

I could be wrong but this contradicts how I was taught while a kid working in service garages. I was always instructed the opposite so no spark would be generated! That means hooking up the positive first and then the negative. Hooking the positive last always or normally gives off some amount of spark. Same thing for hooking up jumper cables. Postive first followed by the ground which I normally use the engine, etc. Maybe back in the late 60's we were taught wrong but I have used that procedure for more years than I like to admit.

Plasticman

Sorry, but your logic "isn't"

A potential spark will be created anytime a current carrying circuit is completed (or broken). It does not matter if the last connection is the negative or positive side of the circuit. The lack of a spark simply means no current flow. The heavier the current flow, the greater the potential spark. There are things that can be done to limit the spark, but current flow direction is not one of them!

It is only where the spark is created that matters.

Plasticman

1-2-b-67L89

You probably know more but even in auto safety courses I attended particpants were instructed to always hook the positive first when jumping a car? Safety protocal is the following per the "battery Coucil International".
Connect positive (+) booster cable to positive (+) terminal of discharged battery.
Connect other end of positive (+) cable to positive (+) terminal of assisting battery.
Connect negative (-) cable to negative (-) terminal of assisting battery.
MAKE FINAL CONNECTION OF NEGATIVE (-) CABLE TO ENGINE BLOCK OF STALLED VEHICLE, AWAY FROM BATTERY.
Start vehicle and remove cables in REVERSE order of connections.
I use the same for hooking up a battery charger. Never noticed any spark hooking up the negative last but as you mention, maybe that is only due to it was mimimized. Do not disagree with your logic but believe that is the reason the shut off is on the negative terminal instead of positive. Thanks and we are always learning

Chuck72

as pertaining to cars, I disagree 100%! on a negative ground system, attaching neg to batt first will get you a face full of battery acid if your wrench grounds out, arcs and lodges, when attempting to attach pos lead.
chuck

62Jeff

The reason you make the last connection to a ground point away from the battery, is so that any spark you generate won't ignite fumes coming from the battery.

Paul L

chuckievette,
Interesting opinion. Never heard that view before. I can't follow your logic.