Trunk mounted battery

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67Dart273 said:
You guys might want to listen

The "crash guys" should be able to run up to the car, KNOW that they can "kick at" the disconnect and KILL ALL POWER and that the disconnect will kill the engine as well as get rid of all power in the car

That toggle switch is not gonna do you any good if you are laying there half goofy in the driver seat and likewise that no6, no 4 charging line from battery to alternator makes a fine welding wire if it does not go through the disconnect

You can thank "all that tom foolery" when you are laying there upside down with fuel running down your nose, eh?
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The secret to the toggle switch is make sure the alternator is turned off before the run. We had a toggle switch on a Mopar that opened the field circuit. It was mounted so it pointed up in the off position. A crew member would look in the car and make sure the driver had all switches in the up position, that meant the fuel pump, water pump, fan, and alternator were ready to race.
Also, why have the parasitic drag of an alternator charging while you're making a run?
 
skykeith said:
The secret
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Sorry, this doesn't "wash."

Having used to service HVAC and heating / gas / oil, NO safety device can ever depend on someone having to manually shut it off. That does not fly.

This kind of thinking is in part why GM right now is in some pretty big ****.
 
You can cut the field, BUT, the charge wire is STILL HOT ALL THE TIME!

What are the termination points for that charge wire? You running that through a toggle as well?

Here's a method that lots of people use and passes tech. See where the issue may lie?

 
My point was that a single switched battery cable coupled with a two wire alternator will make everything go dead by simply turning off the one, lone cable and not having to rely on a solenoid not hanging. (They're pretty good, but they're not perfect and in a crash "pretty good" isn't good enough.) As far as I'm concerned the fewer components in the system the fewer failure modes there are in the system. KISS rules.

The charge wire is only hot when the switch (battery kill, not toggle) is on IF the switch is between the battery and everything else. I used the OE power wire to the alt's regulator for the exciter to my Bosch 90A install, and then I tested that the kill switch did actually kill the engine. In my case it is in the ground wire, not the hot wire.
 
ntsqd said:
My point was that a single switched battery cable coupled with a two wire alternator will make everything go dead by simply turning off the one, lone cable and not having to rely on a solenoid not hanging. (They're pretty good, but they're not perfect and in a crash "pretty good" isn't good enough.) As far as I'm concerned the fewer components in the system the fewer failure modes there are in the system. KISS rules.

The charge wire is only hot when the switch (battery kill, not toggle) is on IF the switch is between the battery and everything else. I used the OE power wire to the alt's regulator for the exciter to my Bosch 90A install, and then I tested that the kill switch did actually kill the engine. In my case it is in the ground wire, not the hot wire.
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That is not legal, pulling ground, per the NHRA rulebook. It MUST disconnect the positive side.

Please show me how you wire this to keep the charge wire from being hot with a legal positive side 2 pole master switch.
 
Why should I? I don't give a damn about the NHRA rule book for my street car.

Now let's say that I did put it in the hot wire. With the switch off the only way that the charge wire can stay hot is if the alt is still producing, which with the battery turned off it should not be doing.
 
ntsqd said:
Why should I? I don't give a damn about the NHRA rule book for my street car.

Now let's say that I did put it in the hot wire. With the switch off the only way that the charge wire can stay hot is if the alt is still producing, which with the battery turned off it should not be doing.
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YOU ARE SO WRONG and off base here. What about the backfeeding that will occur?

You want to debate, start a new thread thread with the rest of the guys pissing in this guys thread, who happens to be going to an NHRA track, where you all can discuss such tom-foolery of extra parts to make the car safer.

People wonder why I don't post as much here, here you go!
 
skykeith said:
Also, why have the parasitic drag of an alternator charging while you're making a run?
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Because it's not just there to charge the battery. It is there to run the rest of the electrical system up to and including the ignition system that might otherwise suffer without the alternator. With an ignition system not getting a full charge from the alternator, or none at all, how can it possibly get the proper charge to the plugs?
 
crackedback said:
YOU ARE SO WRONG and off base here. What about the backfeeding that will occur?

You want to debate, start a new thread thread with the rest of the guys pissing in this guys thread, who happens to be going to an NHRA track, where you all can discuss such tom-foolery of extra parts to make the car safer.

People wonder why I don't post as much here, here you go!
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You can theorize all you want, in the past when I HAVE put the kill switch in the pos side it has killed the engine and all electricals when turned off. The difference is that I did not use a one-wire, self-exciting alternator. AFAIC those are the problem and the NHRA tried to solve it the wrong way. If they don't really understand the problem or electricity they should educate themselves before making a rule. AFAIC it should be simple, does turning off the kill switch kill the engine and the fuel pump? If yes, the car passes. If no, then it doesn't pass. That is what this is all about, turning off the engine and the fuel pump in the event of a crash to buy the driver more time to get out of the car or be pulled/cut out.

If the OP insists on using a self-exciting alternator then there are exactly two options to meet the NHRA rules. One is to run the charge wire to the battery side of the battery kill switch. The other is to use a constant duty solenoid, rated for at least the alt's max output. The Ford type of starter relay/solenoid is not constant duty and is not a good choice for this use at all. The common choice will be a Cole-Hersee product, which are good enough parts for what they are intended to do, but I wouldn't stake my life on them.

If the solenoid isn't mounted within a couple wire inches of the alternator or there is no solenoid, then good practice dictates that it be fused or have a breaker close to the alternator. No, I've never seen an OE do this either. Doesn't make it right, just economical for mass production. If this wire is to make the run to a rear mounted battery kill switch then good practice also requires a fuse or breaker at that end of the wire.

Your attitude is what started this, I only responded to it. I wouldn't call 12k+ posts hardly posting, but what do I know?
 
Yes, and I'm going to leave it at that.

Got to thinking about "what if turning off the battery kill switch hadn't turned off the car" on those past positive-switched vehicles?

There are solutions for that which still do not require a solenoid. There are battery switches that include one or more sets of low current contacts which can be used to turn off the alt's exciter circuit, or the IGN, or both. Two samples:

http://www.rallylights.com/all/elec...y-master/tt061-battery-master-switch-fia.html
TT061_lg_1.jpg


http://www.rallylights.com/all/elec...master/sp01335-battery-master-switch-fia.html
SP01335_lg_1.jpg
 
ntsqd said:
Why should I? I don't give a damn about the NHRA rule book for my street car.
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Yep it's my attitude because you can't stay on point. Yep...

Neither one of those are a 2 pole switches. Good job. Again, not staying on point...

When those fail you are out $50+ each time. 2 pole and a CD cost less to start with and you replace one of them with a failure. Less $'s with a component replacement. He's got a 1 wire alt IIRC, so the exciter and all the other stuff is moot.

You have the same number of failure points in the switches you posted.
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If the OP insists on using a self-exciting alternator then there are exactly two options to meet the NHRA rules. One is to run the charge wire to the battery side of the battery kill switch. The other is to use a constant duty solenoid, rated for at least the alt's max output. The Ford type of starter relay/solenoid is not constant duty and is not a good choice for this use at all.
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So you decided to just muck up the thread and come back to what has been said from the very beginning or exactly what the OP's schematic displays. Nicely done! LOL

At least you got on point with that one. Good job.
 
I guess we're going to have to agree to disagree. You come across as confrontational and then put it on me when I respond in kind. Sorry, not going to accept that. It isn't just this thread, there was a similar thread not long ago on essentially the same topic.

There is always more than one way to do something, yet yours is the only option that you're willing to allow others to consider. Maybe that lack of tolerance is why you don't post here so much?

I'm done with this. Post a response if you feel the need. I won't be reading it, this has spiraled badly enough.
 
Welding cable is very flexible and high current as an option.
 
Asking for a schematic of a one wire set up that kills the charge line from being hot using a 2 pole switch is confrontational. I want to see what others are suggesting.

OP has a one wire alternator. The exciter wire conversation is irrelevant to HIS situation.

Lots of ways to do things, some safer than others using specific components.
 
Hmmm.... Interesting "conversation". Many good points made by all, however if your going to run a sanctioned event you have to abide by the sanctioning body's rule book whether you agree with it or not. Anything can be accomplished in many different ways and all posted here gets the result that person is looking for. Are there safer ways to do it, sure. Crackedback has generously posted many times, many ways to safely wire up a trunk mount/disconnect switch system and they are time proven to pass NHRA tech. Will they pass SCCA or other sanctioning body rules? Don't rightly know. Get the rule book and find out. On a street car you can damned well do anything you like but you better hope the thing doesn't catch fire when you/your family is pinned inside.

By the way, if I'm not mistaken, plastic handle cut off switches aren't allowed by any racing organization.
 
Cracked back's dead on. I wouldn't use anything less than the Moroso style switch, and shutting off the positive side cable,for cutoff.A fellow trailered his Chevy,to Famoso. He failed tech,becauseof cut off switch issues. He was in the pits making it legal,while who I was with made three passes.Get it right,the first time.
 
Fst73_360 said:
Arent most cut off switches plastic?
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Only the crappy ones. See any plastic here?

mor-74100_ml.jpg


CB and 67Dart273 are right on. Do it right the first time. Might cost more up front, but it'll be cheaper (and safer) in the long run.

The battery cutoff for the track is a safety item. It's there, and required to be a specific way, for your safety. Why would you want to mess with that?
 
The thing about "quality"

I don't know anymore. Used to be Cole Hearse and other brand names were "good." So was Standard / Blue Streak and Echlin and a bunch of other name brand American brands. I don't know, anymore. Still, Most anything that is sold as "marine grade" is still pretty fair

Someplace I recently saw a Moroso I think that was 4 terminal I believe, rated at 300A

Here ya go

http://www.jegs.com/i/Moroso/710/74102/10002/-1

300A continuous, 2000A intermittent, with 2 auxiliary terminals for your ignition/ other circuit.
 
67Dart273 said:
The thing about "quality"

I don't know anymore. Used to be Cole Hearse and other brand names were "good." So was Standard / Blue Streak and Echlin and a bunch of other name brand American brands. I don't know, anymore. Still, Most anything that is sold as "marine grade" is still pretty fair

Someplace I recently saw a Moroso I think that was 4 terminal I believe, rated at 300A

Here ya go

http://www.jegs.com/i/Moroso/710/74102/10002/-1

300A continuous, 2000A intermittent, with 2 auxiliary terminals for your ignition/ other circuit.
Click to expand...

As a parts guy,Cole Hersee still good parts Del......
 
Its been years since I read a NHRA rule book but if my memory serves me correctly the handle, paddle, flipper dodad... whatever you want to call it, cannot be made of plastic or be of the removable type ie slide in to engage the switch. As stated it is a safety device. Track personnel have to be able to quickly identify the switch and deactivate the cars electrical system in the event of an accident/incident. Make sure the switch you choose can handle the continuous amp output of your alt. There are a lot of low amp rated switches on the market.
 
rapom65 said:
By the way, if I'm not mistaken, plastic handle cut off switches aren't allowed by any racing organization.
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Just for reference, I am not aware of any rally sanctioning organization worldwide that dissallows plastic bodied or handled switches......The main reason I think this is allowed is that the switrches for FIA rally have to be mounted with the handle external so someone can turn it off from the outside; a common mounting point is at the base of the windshield. With a plastic handled switch, the handle is removable for security, and it will handle the weather better; rallies go on in ALL weather. I have never seen or known of one to fail.

I recall years ago that SCCA would not allow non-metal ones, but I am not sure that is true any more.

IMO.... taking any sanctioning body rulebook as the sole reason to do this or that is not very reliable. Having sat on a sanctioning body rules committee for a few years, I learned that most of the time there was no perfect solution, and all you can do is try to find the best available. Often there is more than one equally good way, but just one of those ways will go into the rulebook (without creating a lot of confusion for the competitors!).

I like crackedback's note that there is a 2' cube of space where things can still go wrong; it is good but nothing is perfect. You'll find that wrecks can and will occur in all sorts of crazy and unpredicatable ways once you have enough crashes 'in the books'.

And I have yet to personally see a Ford starter solenoid hang, with thousands of starts in Fords. They seem pretty reliable, even with all sorts of banging around. I have only see them fail to close when they get burned on the disc. (I worry more about solid state relays failing; I am an electrical engineer and say this!) Regards....
 
The one i got was water proof ****... I looked the moroso but I don't think it was waterproof hmm
 
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