Battery Dis-connect

[Ralph E.]

Re: Another Question

I put mine on the negative terminal per the directions. Also, once the motor has started I always thought you didn't need the battery. I'm assuming you have an alternator not a generator.

[John H.]

Re: Another Question

George -

I have always put mine on the negative (ground) terminal - when it's disconnected, there is no ground path from anywhere in the car back to the battery, so you can drop wrenches to your heart's content on the positive terminal (or any other "hot" point in the car) with no fireworks. I used to argue with NHRA Tech Inspectors on this same issue, as NHRA rules require the disconnect on the positive terminal, but I gave up and put my (remote) disconnects on the positive terminal where the NHRA wants them on my race cars.

[John H.]

Re: Another Question

George -

I have always put mine on the negative (ground) terminal - when it's disconnected, there is no ground path from anywhere in the car back to the battery, so you can drop wrenches to your heart's content on the positive terminal (or any other "hot" point in the car) with no fireworks. I used to argue with NHRA Tech Inspectors on this same issue, as NHRA rules require the disconnect on the positive terminal, but I gave up and put my (remote) disconnects on the positive terminal where the NHRA wants them on my race cars.

[Jack H.]

Careful fellas!!!

The switch could care less whether it open circuit's the battery path to ground or the positive path to downstream branch circuits. Open circuit is open circuit.

However, there ARE a few nuissances to consider which could impact and be the reason for mfg's recommendation(s) on mounting.

(1) If the switch wears and starts to build up contact resistance, what is the impact on your car's charging system???? If the IR drop is from the positive post, the voltage regulator 'sees' a battery charge state that's SMALLER than actual and will try to 'overcharge' the battery to compensate. If the IR drop in the switch contact is on the negative post, this tends to push the battery below ground for the opposite effect (undercharging).

(2) Poster failed to state what kind of switch/battery he was dealing with. Hey, specifics help! Take a micrometer and measure post diameter on a conventional top post battery. There IS a size difference between POS an NEG. Putting cutoff switch designed to cinch tighly to a given post OD on the wrong post could have consequences on torque down, effective contact area, Etc.....

(3) Also, subtle diffences are involved in the geometry of side post batteries. See #2....

Suggest some of the advice given you in this thread may be a disservice! Check it out before you decide/install. Of course, for geometry issues, shims CAN be made and used....

[Jack H.]

Careful fellas!!!

The switch could care less whether it open circuit's the battery path to ground or the positive path to downstream branch circuits. Open circuit is open circuit.

However, there ARE a few nuissances to consider which could impact and be the reason for mfg's recommendation(s) on mounting.

(1) If the switch wears and starts to build up contact resistance, what is the impact on your car's charging system???? If the IR drop is from the positive post, the voltage regulator 'sees' a battery charge state that's SMALLER than actual and will try to 'overcharge' the battery to compensate. If the IR drop in the switch contact is on the negative post, this tends to push the battery below ground for the opposite effect (undercharging).

(2) Poster failed to state what kind of switch/battery he was dealing with. Hey, specifics help! Take a micrometer and measure post diameter on a conventional top post battery. There IS a size difference between POS an NEG. Putting cutoff switch designed to cinch tighly to a given post OD on the wrong post could have consequences on torque down, effective contact area, Etc.....

(3) Also, subtle diffences are involved in the geometry of side post batteries. See #2....

Suggest some of the advice given you in this thread may be a disservice! Check it out before you decide/install. Of course, for geometry issues, shims CAN be made and used....

[John H.]

Re: Careful fellas!!!

I have two brand new "Green Wonders" hanging on the wall (cars come, and cars go); they are designed to go over the negative post (top-terminal type) on the battery, and fit that post perfectly; the clamp end would have to be spread open excessively in order to fit all the way down on the (larger) positive post.

[John H.]

Re: Careful fellas!!!

I have two brand new "Green Wonders" hanging on the wall (cars come, and cars go); they are designed to go over the negative post (top-terminal type) on the battery, and fit that post perfectly; the clamp end would have to be spread open excessively in order to fit all the way down on the (larger) positive post.

[George J.]

Re: Careful fellas!!!

John,

can I make an offer on the red one?

George

[George J.]

Re: Careful fellas!!!

John,

can I make an offer on the red one?

George

[John H.]

Re: Careful fellas!!!

George -

That one only understands offers in Italian

[John H.]

Re: Careful fellas!!!

George -

That one only understands offers in Italian

[Patrick H.]

10,000 lira *NM*

[Patrick H.]

10,000 lira *NM*

[John H.]

Re: 10,000 lira

Patrick -

That's about $4.62 - you gotta up the ante some more

[John H.]

Re: 10,000 lira

Patrick -

That's about $4.62 - you gotta up the ante some more