Battery cut off

[elwood]

Hey guys Im running a battery cut off switch on my coupe, I have the volt meter wired directly to the regulator, and like to disconnect the battery when I park it at night,
So in 2 years this is the second regulator that's gone bad, just put the 3rd on this morning.
Do you think disconnecting the battery on a generator charging system will de-polarized it, and maybe, over time, hurt the regulator somehow.
Thanks ..

[ford38v8]

Elwood, I don't know why you even mention the voltmeter, but as you have, I'll address that first: A correctly installed voltmeter is not wired directly to anything, but rather, it has a loop in the back that the insulated hot wire passes through. It may be passed through in either direction without problem but for the correct reading of the voltmeter showing charge when the engine is revved, the other incorrect direction showing discharge when the engine is revved.

Disconnection of the battery can be done without issue, and in any case would not affect the polarity of the regulator. It is the generator that may need to be polarized if replaced, but the same generator will remain polarized whether or not the battery is disconnected overnight or between seasons.

The battery Disconnect switch itself may ultimately prove to be the source of your problem, as most switches you see these days are not adequate for a 6 volt system. Being intended for a 12 volt system, they offer resistance to the circuit that prevents the charging system from doing it's job. If you insist on using a switch, there are 6 volt switches available, but do not use the battery post green knob type, which is a 12 volt model.

[tubman]

Uh, the meter with the loop in the back that has the hot wire passing through it is an ammeter, not a voltmeter. Also, an ammeter can be wired "in-line"; I have a couple of Stewart Warner units that are configured that way.

[ford38v8]

Originally Posted by tubman

Uh, the meter with the loop in the back that has the hot wire passing through it is an ammeter, not a voltmeter. Also, an ammeter can be wired "in-line"; I have a couple of Stewart Warner units that are configured that way.

Oh oh. Got it wrong again. Thanx for the correction.

[51 MERC-CT]

I have owned flathead Fords during the time that they were still being produced.
At no time did I ever use a battery cut off switch on any car I ever owned.
Am I missing something? Is there any advantage to have a switch? And what will happen if I don't have one? Curious.

[TagMan]

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Originally Posted by 51 MERC-CT

I have owned flathead Fords during the time that they were still being produced.
At no time did I ever use a battery cut off switch on any car I ever owned.
Am I missing something? Is there any advantage to have a switch? And what will happen if I don't have one? Curious.

Years ago, I opened my garage door to take an old car for a ride and immediately smelled the acrid smell of burnt electrical wiring. The ammeter had shorted out and melted the wire insulation. Luckily, nothing else had caught fire. I could have lost my car, garrage, house, even my family. Ever since then, all my old cars have had battery shut-offs installed.

[Flathead Fever]

My understanding is once you polarize a generator its stays polarized. Turning off a battery switch should not effect it. You usually only polarize a generator once on a new installation. The regulator is not polarized, the generator is.

It could be poor quality regulators. Do not buy "any" electronic parts from these big chain auto parts store except for Napa. The parts are junk!

I never understood the reason for installing a cutoff switch. No factory built car ever came with one. Nobody worries about putting one on there modern cars but they are worried about their vintage ones. Just make sure your wiring is good. That extra switch and cables just means more possible resistance spots that will drop your voltage. If your not going to use the car for a long time disconnect the battery. Otherwise it should be fine without a cutoff switch. If its hot rod and your not staying completely original. Every circuit except the starter should have a fuse. Then there is no reason to have a battery switch

Somebody is going to say they know somebody whose car burned to the ground because of an electrical short. I'm sure it happens but a well maintained vintage car with new wiring should not have any problems.


If the voltmeter is hooked to the battery connection on the regulator then it would be on all the time and kill the battery. It should be connected to voltage controlled by the ignition switch

[elwood]

Hey guys, thanks for the replies,
Guess I should have clarified myself in the original post, yea, the car I'm talking about is the Deuce in my Avatar, its 12 volt, and I do have the volt meter wired directly to the battery post on the regulator, reason is I like seeing exactly whats coming from the generator,
The cut off switch I have hooked up is spliced in the Main Positive battery cable, about 4 inches from the battery post, everything is clean and soldered, no issues .
Thus the reason I like to disconnect the battery, as not to drain it .
I actually bought a NOS Ford regulator off ebay, and it didn't work out of the box, and this is my 3rd one from O'Reilly's, put it on this morning and is working great, lol ..
The sticker on the regulator cover says to flash the field lead across the battery lead, then hook up the field, " Polarizing " it ?

[G.M.]

You don't want to use those cheap battery disconnects
with the green knob. These are made of pot metal and
anodized to look like they are brass. They don't hold up
very well. G.M.

[paul2748]

I think you should use the cutoff on the ground side of the battery. That is the recommended place for a shut off.



I think having the voltmeter attached to the regulator may be your problem. I'm no electrician so I can't say that for sure. A voltmeter may be connected to any 12 volt source and preferably to one that is activated by the key. Leaving it on all the time (like when going to shows) just drains the battery. I suggest connecting to some other source controlled by the ignition switch.

[Pete]

Originally Posted by elwood

Hey guys, thanks for the replies,
Guess I should have clarified myself in the original post, yea, the car I'm talking about is the Deuce in my Avatar, its 12 volt, and I do have the volt meter wired directly to the battery post on the regulator, reason is I like seeing exactly whats coming from the generator,
The cut off switch I have hooked up is spliced in the Main Positive battery cable, about 4 inches from the battery post, everything is clean and soldered, no issues .
Thus the reason I like to disconnect the battery, as not to drain it .
I actually bought a NOS Ford regulator off ebay, and it didn't work out of the box, and this is my 3rd one from O'Reilly's, put it on this morning and is working great, lol ..
The sticker on the regulator cover says to flash the field lead across the battery lead, then hook up the field, " Polarizing " it ?

You are drawing current from the battery through the regulator with the voltmeter hooked up as you do. The current is very small, maybe only 5 milliamps at most but it is there all the time when the main switch is on.
With the cheap quality of the chink made electrical stuff, this could very likely be why regulators are failing in your setup.

[TJ]

Originally Posted by paul2748

I think you should use the cutoff on the ground side of the battery. That is the recommended place for a shut off.



I think having the voltmeter attached to the regulator may be your problem. I'm no electrician so I can't say that for sure. A voltmeter may be connected to any 12 volt source and preferably to one that is activated by the key. Leaving it on all the time (like when going to shows) just drains the battery. I suggest connecting to some other source controlled by the ignition switch.

Paul is correct. If you have a voltmeter it should be connected to the ignition side of the switch. It needs to be shut off with the ignition. Having the volt meter connected directly to the battery is a constant drain on the battery.

[qmdv]

Not running a cut off for my battery. Eliminating the leaks is a better idea for me

[Drbrown]

I have a 12v system with Alternator (no generator or separate regulator).

DISCONNECTS: I use a relatively expensive brand 4-post turn-knob type master shut-off switch mounted thru the fire wall so the on-off knob is inside the car by the heater - not easy to see but not hard to reach. I use to have an inexpensive on-the-battery-post type knob but did not like opening and closing the hood all the time and possibly damaging the paint finish..

I use it because (1) my car may sit for a month or more, and (2) my clock and (modern) radio draw current all the time the battery is connected to the system. Theft/security is a secondary concern. When these cars were/are daily drivers having the clock and/or radio draw current is not a problem.

My master switch has four terminals - the second set of terminals connect/disconnect the my Alternator from the system. The intention is that with a conventionally wired system, if the engine is still rotating an Alternator (as opposed to a generator) can keep feeding the ignition system with current even if the ignition switch is turned off and/or battery is disconnected from system. So its a partial fail-safe idea I've only read about and I've never tested the theory.

VOLT METERS: I connect mine near an Alternator output location (i.e. main devise connector terminal) so I can see what the Alternator is putting out and what the system is "requesting". A stock Amp meter doesn't tell you much. I have both using after-market units. If one has an electronic ignition module (instead of points) having a volt meter is important because many modules are extremely sensitive to voltage fluctuations. I had several Pentonix burned out ($$$) due to Alternator fluctuations so I changed to a stock points set up and have had no problems since.

[Flathead Fever]

I would wire up your coupe just like a '57 to '64 Ford with a 12V system, a generator and a voltmeter (some had idiot lights). Take a look at how the Ford engineers wired it.

[qmdv]

Originally Posted by Flathead Fever

I would wire up your coupe just like a '57 to '64 Ford with a 12V system, a generator and a voltmeter (some had idiot lights). Take a look at how the Ford engineers wired it.

My dad bought a new 57 Ford Fairlane 500. I do not remember a battery cut off on it

[elwood]

Flathead Fever, that's what Im going to do,
Thanks for all the replies guys ...

[Ggmac]

Back in the day MOST cars were parked outside and not collectable or 50plus yrs old .
It nice to go to bed knowing your prized car won't burn the house down . I know mine are parked in the house garage or the home ( shop ) I built for them .

[swedishsteel]

I installed a hidden battery cutoff switch in my '36 five window so some a$%%^^e can't hot wire it in the middle of the night and drive it away. All it takes is a jumper wire on the back of the switch and it's running. Yes, I do lock the steering wheel and take the key out, but every little bit helps. I use it when we are gone overnight and the car is parked on the street or in a hotel parking lot. Merry Christmas to all the 'barners. Rod

[Ggmac]

Merry Christmas and safe roads for the new year