Like

Alternator guestion for GlassWolf or anyone else who knows.

 

New member
Username: Tikolx333

Post Number: 80
Registered: 12-2003
Hey do you think this will work alot better then my stock http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2450806043&categor y=33573

they clame 160amp then in the discription it sais 70-80amp at idel what do you think. take a look.
 

OK
Unregistered guest
well the 70-80 amp at idle is not true... a stock alternator produce 100 amp at idle... so keep urs and sukk a dick
 

New member
Username: Tikolx333

Post Number: 82
Registered: 12-2003
Pardon me sir but the last part was unnecessary just because you enjoy suking dick doesn't mean everyone else does.
 

New member
Username: Glasswolf

Post Number: 486
Registered: 12-2003
there is no set amount of current that all alternators produce at idle.
the alternator will produce less at idle, which is normal, so that 160A should be fine.
 

New member
Username: Santaclaw

Post Number: 3
Registered: 01-2004
Hm.. typpical alternator on a regular small engine car, 1.3 - 3 litre, is annything from 55-120 amp

The alternator (depending on type) delivers the rate ampere at around 3500 rpm, @ idle or about 500 rpm it puts out something like 30-40 ampere is normal.

Just ignore OK, he doesnt know what he is talking about.
 

Billy J
Unregistered guest
i have a system that uses less than 1000 watts max, i have a napa alt. that is 100 amps, my lights n stuff still dim and stuff so what will fix that if a cap serves no real purpose. i have a 95 chevy lumina.
 

New member
Username: Glasswolf

Post Number: 534
Registered: 12-2003
a larger alternator.
 

JOEY
Unregistered guest
My amp is only like 250 rms and 750 max and my lights still dim and stuff, and i dont even know what to do
 

New member
Username: Santaclaw

Post Number: 4
Registered: 01-2004
Ok, There are a few tings to consider.

Let's say your amp is rated @750w in 4 ohms.

It's most certanly rated @ 750w in 4 ohms in 13.3v or more !

A fully charged regular 12v car battery has between 12.5v and 13v.

The alternator usually delivers between 13.8 and 15v, so you all know the watts formula ?? Amp times voltage = wattage or in this case we need to do watts devided by voltage..

750w\13.8v = 54 Ampere, lets say you have an 70 amp generator....

70 - 54 = 16 amps left for the rest of the electrical equipment.

Main lights, cooling fan, ect ++++

Now, when you use MORE than those 70 amps that the generator is capable of delivering, you wil begine drawing power from the battery in stead, and the "idiot, charge light" wil come on.

But the thing is, that with the amplifyer, as you draw power from the generator, the voltage comming from the generator is "used up" by the amp, voltage can be seen as the pressure inside a gas cannister, as the pressure drops, so does the flow of gas(Liters\min) that escapes the canister, that means, Less voltage, less amps..

So the more load you put on the alternator, the more voltage you "use" to force more electrons through the amp, Therefore, when the car lights blink, it's because the amp draws so much power that the generator cannot keep the voltage @ the same level constantly, causing the lights to get less wattage = less lights.

Badly explained, sorry, native Norwegian, bad English...
 

New member
Username: Glasswolf

Post Number: 570
Registered: 12-2003
ok now to correct a few things:

-It's most certanly rated @ 750w in 4 ohms in 13.3v or more !

incorrect. that depends on two things.
the company's rating policy, and if the power supply is regulated or not.
many better companies give power ratings at both 12V and 14.4V if they use unregulated power supplies, and if the supply is in fact regulated (think JL Audio) then the output will be the same regardless of input voltage, from about 9 to 16VDC.

-A fully charged regular 12v car battery has between 12.5v and 13v.

wrong. a battery is 12V. period. If it's discharged, that will drop, but the battery should never read higher than 12V. If it does, the alternator won't be able to reach a great enough bias to recharge the battery when the engine is running.
This however, doesn't matter since the battery isn't used by the car's electrical system while the engine is running. Ideally, when the motor is running, the battery is in a charging cycle.

-Amp times voltage = wattage or in this case we need to do watts devided by voltage..

Yes Ohm's law, but you also need to figure in for the amplifier efficiency based on amplifier class.
~90% for class-D, ~50% for class-B or AB, and as little as 25% for class-A.

-Now, when you use MORE than those 70 amps that the [alternator] is capable of delivering, you wil begine drawing power from the battery in stead, and the "idiot, charge light" wil come on.

well, yes, but your voltage rails will also sag, causing lights to dim, car to misfire, and stall, and so forth, not to mention cause your amplifier(s) to clip, which will cause both distortion, and damage to the speakers.

-But the thing is, that with the amplifyer, as you draw power from the generator, the voltage comming from the generator is "used up" by the amp

no sir. the current is used up.
the voltage should not alter unless the alternator is over-worked and cannot keep up with the system demands.

-voltage can be seen as the pressure inside a gas cannister

ok instead of confusing analogies, let's just define a few things outright.
Current is the measure of the flow of electrons passing through a given point in a circuit in a given amount of time. The unit is the ampere.

Voltage is the measure of difference of potential (electrical force) between two points. The volt is the unit of measure.

Resistance is the measure of a device's opposition to the flow of electrical current. Its unit of measure is the ohm. The term "resistance" applies to Direct Current, whereas the term, "impedance" applies to alternating current.

again, for information on charging systems, see the following two links that nobody here seems to bother reading, so I have to keep repeating myself in these posts:
http://pub14.ezboard.com/fcaraudiotalkfrm27.showMessage?topicID=23.topic
http://www.bcae1.com/charging.htm
 

New member
Username: Santaclaw

Post Number: 5
Registered: 01-2004
-A fully charged regular 12v car battery has between 12.5v and 13v.

wrong. a battery is 12V. period. If it's discharged, that will drop, but the battery should never read higher than 12V. If it does, the alternator won't be able to reach a great enough bias to recharge the battery when the engine is running.
This however, doesn't matter since the battery isn't used by the car's electrical system while the engine is running. Ideally, when the motor is running, the battery is in a charging cycle.

Because if what you where saying is true, you might be in for a supprise if you take you voltage messuring device out to you car's battery after charging it compleatly.

It won't be @ 12v, that i can promise you.

You see, althoug the car has a 12V system, both the alternator and the 12v battery arent rated @ 12v..

The battery's 6 cells is supposidley 2 volts each ??

WRONG !.

They are acctually more like 2.1 volts each, producing a battery @ 12.6 volts.

Another thing, there is a reason why the alternator can "safely" charge with up to 15v.

If you didnt know that an alternator does that, i can't belive you have any automitive experience.

Also, just to get this straight, when the car is running NOTHING shold draw more combined amps than the alternator is capable of delivering.

-But the thing is, that with the amplifyer, as you draw power from the generator, the voltage comming from the generator is "used up" by the amp

no sir. the current is used up.
the voltage should not alter unless the alternator is over-worked and cannot keep up with the system demands.

You don't know much about electronics @ all eighter ?

Ok.

What is Voltage ?

What is Ampere ?

What is Resistance ?

To understand, think of the wire as an ordinary garden hose, where voltage is pressure, and Amps is flow in liters per min, and resistance is yes, well resistance, f.eks if you squeeze the hose in one place, resistance wil increase, and the preassure/voltage will remain @ the same level before the "crimp" and after, but, the amps, wil dropp accordingly, but if you connect a large hose @ the end of the wire without a "resistance" such as a large amplifyer, drawing "too much power" the amps, or Liters per min wil poor out without resistance, and the preassure or "voltage" wil drop.

This means that when you overstress the alternator, the voltage wil gradually drop (as the resistance decreases) causing the lights to dim, as the amplifyer draws current in "pulses".

The current the alternator is delivering is NOT decreasing as you put load on it, its acctually increasing. But the xtra curent comes at the price of lesser voltage.

The reason the alternator "remains" at 13.3v under load is because it's actually producing MUCH more than 13.3 volts, its the voltage regulator that's "reducing" it to 13.3v, according to need.

But as you approach the "limmit" of what the alternator is capable of delivering, the voltage wil drop below what the alternator is capable of.

Causing the voltage to drop below 13.3v

Sorry, I don't have time to give you a "propper" explenation, cauz i need to get to woork, and I'm a bit rusty on the "terminolegy".

Also

Quote from : http://www.bcae1.com/charging.htm

"Battery Construction:
A standard 12 volt cranking battery has 6 individual cells. Each cell is designed to produce ~2.1 volts. The cells are connected in series for a total of about 12.5 volts. Each cell basically consists of 1 set of lead plates and 1 set of lead plates coated with lead dioxide submerged in a sulfuric acid electrolytic solution"
 

New member
Username: Glasswolf

Post Number: 575
Registered: 12-2003
a: I know a lot more about alternators, and electronics than you do.
I'm an E.E., and I have over a decade of professional installer experience.

b: please.. learn to spell.

c: you're still wrong on the majority of what you think you know.

d: stop trying to misquote me. a number of things you try to imply me stating are completely in your head, or a matter of your inability to comprehend what I've said. The alternator can only put out X amount of current. Once that peak is reached by the demand of the devices on that circuit, voltage rails begin to sag. Period. The alternator puts out a higher voltage (graeter differential) than the battery. It has to. That's how the battery is re-charged. If the battery was 13V, and the alternator put out 13V as well, the battery wouldn't charge, due to a lack of bias on the circuit.

and yes, I'm aware of how a battery is constructed. What you see on paper (or your website) doesn't accound for efficiency, or any number of other factors that also affect a battery's capacity, charge, and so forth.
If you'd like to know what my batteries read on a DMM, they all read between 11.9 and 11.97VDC.
My alternator, on the other hand, puts out 14.4VDC after voltage regulation.
 

New member
Username: Glasswolf

Post Number: 577
Registered: 12-2003
addendum:

sorry I won't be around for a while to banter with you.
I'm off in an hour or so for surgery, so I'll be gone from the forums for a bit. Looks like you get the last word on this thread. :P

take it easy
 

New member
Username: Motoman22

Post Number: 60
Registered: 12-2003
"What is Voltage?"
-A cool toy from the '80s that used five robot lion toys merging into one big kick-butt good guy. Wait, his name was Voltron...my bad.

"What is Ampere?"
-the absense of 'mpere'

"What is Resistance?"
-when you fight a police officer. Bad news...don't resist, it's futile.

"A fully charged regular 12v car battery has between 12.5v and 13v."

A fully charged regular 12v car battery connected to a fully charging alternator can appear to have upwards of 14.4v. That's what the alternator is putting out, not what the battery is producing through chemical reaction.

The design of the 12v battery is that each individual cell may have a total energy production potential of nearly 13v BUT this is to compensate for parasitic loss. If a battery, all by itself with no charging system connected, is producing more than 12v continuous...something's wrong with it and you should probably wear eye protection. When they blow it's not pretty.
 

New member
Username: Santaclaw

Post Number: 6
Registered: 01-2004
Quote from : http://www.bcae1.com/charging.htm

"Battery Construction:
A standard 12 volt cranking battery has 6 individual cells. Each cell is designed to produce ~2.1 volts. The cells are connected in series for a total of about 12.5 volts. Each cell basically consists of 1 set of lead plates and 1 set of lead plates coated with lead dioxide submerged in a sulfuric acid electrolytic solution"


GlassWolf, im sorry if I was rude.

But if im not misstaken it was actually YOU that came up with that web site of mine...

I only know what I know, until I get a proper xplenation why my teories are incorrect.

:-)

Sorry if I was a bit rude.

As I explained before, I do not have English as a Native Langauge, and the little English I know, is self learned.

What happends if you remove the voltage regulator, and im NOT speaking of the "direct current" diodes.

The alternator wil output between 90-100v dc, as you connect power consumers, the voltage wil drop gradually until you hit 13.3v.

Because the voltage is what "drives" the current, voltage WIL dropp as you draw current, if your alternator's regulator issnt electronic, it might be to slow to compensate for the sudden current spike, causing the voltage to drop, witch in terms means the lights blink.

 

New member
Username: Santaclaw

Post Number: 7
Registered: 01-2004
Hm.. ok, if you insist.

Michael, what stops the battery from blowing up when its chaged with 15v ???

When the battery is fully charged, you can't force more electrons into it, without upping the voltage.

but when the car battery is charged @ max, it IS approx @ 12.5v

I have a few years education in Cars' and electronics, five years in total, so I can't belive that EVERYTHING is incorrect.

I want to know WHY it is.

Not what you Think you know.
 

New member
Username: Tikolx333

Post Number: 94
Registered: 12-2003
Lol electrical nerds fighting it out. Its all good I wish I knew as much as you guys about that stuff.
 

THE TRUTH!
Unregistered guest
BUY A CAP READ THE POST ABOUT WHAT IS A CAPACITOR FOR. A CAP DOES SERVE A PURPOSE IT IS NOT JUST A MARKETING SCHEME... I had to replace the alternator in my car 2 times and the 2nd one was a high output alternator but guess what! thats not what i needed... I talked to the dealership of my car and they said to buy a CAPACITOR and that would solve my problem. Each of those alternators only lasted about 7 months in my car (I have a 3400 watt system) but since i added capacitors I have had no problems (the 3rd alternator i purchased was a factory alternator from a scrap yard) the new alternator has lasted over 3 years now! CAPACITORS ARE NOT A SCAM!
 

New member
Username: Glasswolf

Post Number: 579
Registered: 12-2003
both Mike and I explained precisely why the battery's actual output will be 12VDC, which is also what you'll read at any point in the car on a meter. While ise, each of the six cells does inteed, theoretically produce 2.1V, there are other factors, as noted above, that make the final real world output right about an even 12VDC.
at any rate, the main point here was simply that the alternator has to produce a significantly higher voltage than the battery in order for the lead-acid battery to be re-charged. That's all.

"I do not have English as a Native Langauge"

I can totally accept that. I might recommend that you look into an English spell-checking program if you do much writing in English though. I've seen several that will spell-check for any program you run, by working as a TSR. Really handy stuff :-)

"What happends if you remove the voltage regulator, and im NOT speaking of the "direct current" diodes.
The alternator wil output between 90-100v dc, as you connect power consumers, the voltage wil drop gradually until you hit 13.3v."

erm, ok actualy the alternator itself (as the name implies) without a voltage regulator, actually produces AC voltage, not DC at all. The voltage regulator rectifies that AC to DC, then allows you to adjust the output voltage to what is needed for the car. In my case, with high output alternators, I set the regulators to 14.4VDC.
The current supplies will be as much as is demanded by the load on the circuit. The voltage rails, ideally, should remain stable and not fluctuate.

"Michael, what stops the battery from blowing up when its chaged with 15v ?"

Ok, when a lead acid battery is recharged too quickly, or at too high of a voltage from the alternator, or when the battery is heated, it "gasses" which means it begins to bulge, and produce moderate to large amounts of hydrogen gas.
When that gas is ignited, you end up with a small, non-nuclear hydrogen bomb. It's not a pretty thing to see happen, and it does happen. That's why maintaining a healthy electrical system is very important. When batteries are drained below about about 10 volts, you also run a very good chance of damagine one or more of the cells in the battery, at which point you need to replace it.
Problem is, people often still try to drive the car with that damaged battery, or try to overcharge it. I'll leave the problems that can cause to your imagination, unless you'd like some details. Let me know. (surgery was postponed/cancelled for now so I'll be around. Doctor decided things looked better so he held off on anything invasinve.)

I didn't mean to say that all of your posts were totally wrong. There were only a few points I wanted to straighten out, mostly on an electrical basics means. I think it wasn't so much that you were wrong, but the translation didn't come across well.

'The Truth' I'll get to your post.
 

New member
Username: Santaclaw

Post Number: 8
Registered: 01-2004
erm, ok actualy the alternator itself (as the name implies) without a voltage regulator, actually produces AC voltage, not DC at all. The voltage regulator rectifies that AC to DC, then allows you to adjust the output voltage to what is needed for the car. In my case, with high output alternators, I set the regulators to 14.4VDC.
The current supplies will be as much as is demanded by the load on the circuit. The voltage rails, ideally, should remain stable and not fluctuate.

If you remove the voltage regulator the alternator wil still produce DC, but at a much higher voltage. It's the three diodes that makes dc out of ac, the voltage regulator does, (As the name implyes) regulate the voltage, from 50-120v to annything from 13.4v to 15.0v, depending on load, what it's set to, and type.

I woluld like to point out that on some alternators, the ac to dc diodes, or the "diode bridge" is located on the voltage regulator, but only if the voltage regulator i mounted inside the alternator.

Ok, here's some usefull tips, when the lights are blinking.

As previusly mentioned, try a capacitor, I recomend 1 fharad per 1000w.

Check all ground points on the car, make sure that there is a deacent size cable between the battery's -pole , and the car's chassis, also check that the battery terminals are clean, in good condition.

There sholuld also be a decent cable between the engine block, and the chassis, because the alternator needs to transfer electricity both to the + and the - pole on the battery.

Also, I would recommend batteries, and alternator(s) from http://www.stingerelectronics.com/

They may be expensive, but they do the trick... :-)
 

New member
Username: Glasswolf

Post Number: 586
Registered: 12-2003
yes the "diodes" are the bridge-rectifier I mentioned.
an alternator however, still produces AC voltage in a three-phase cycle.
"When current (supplied by the voltage regulator) is flowing in the rotor's coils, they induce current flow in the stationary coils. The induced current (and voltage) is an AC current."
and yes some alternators use an internal regularot, and some use an external regulator.
personally, I prefer the external, adjustable ones.
forget capacitors. they won't help. if the alternator is too weak already, a capacitor will help for about 30 seconds before it's energy is completely discharged, and then the alternator is right back to where it was.. as are the sagging voltage rails.
if a cap stops lights from dimming it's only because the voltage rails are now steadily below where they should be, the alternator is still voer-worked, and the amplifiers will still clip.

good suggestion on connection points, and in addition make sure the battery terminals are clean and not corroded away as is common in older cars. Also be sure teh alternator has the same cable as the battery and amplifiers. This especially applies when using a high output aftermarket alternator.

don't put a deep cycle battery as your only battery in the car. this is a bad idea, as deep cycles are usually lower CCA, and not designed to work as a starter battery.
if you go with a high output alternator and you want a battery or batteries for running the system with the car turned off, get a battery isolator, and put the audio system on the deepcycle battery(ies) alone, leaving the higher CCA starter battery isolated from the audio system.

 

New member
Username: Santaclaw

Post Number: 9
Registered: 01-2004
All in all I have 2 stinger 150 amp alternators, and 2x Ma-Audio hc 4002 amplifyers, that are rated @ 4000w each in 1 ohm.

With these I power my two stroker 12d2's delivering over 154 db...

I also have 4 huge 15 fharad capacitors 2 per amplifyer, and 3 stinger batteries on the isolated circet.
 

New member
Username: Santaclaw

Post Number: 10
Registered: 01-2004
146 db if I roll down my front windows... heh
 

New member
Username: Glasswolf

Post Number: 589
Registered: 12-2003
yeah.
My two Cerwin 12" in my IASCA car hit 151 in events on an Orion 280GX (160w x 2) and the same two subs are hitting 147.2dB in my Grand Cherokee on an Orion 2125SX now. (250w x 2) but I'm not into SPL competition at all. I much prefer sound quality, good imaging and soundstage, proper phase and so forth to the loud punks at stoplights.
 

New member
Username: Motoman22

Post Number: 62
Registered: 12-2003
"Michael, what stops the battery from blowing up when its chaged with 15v ???"

In the old days there was a generator to produce power and a separate regulator to protect the cars electrical system but now it's all built into one device called an 'alternator.' It has internal devices that monitor how much power the battery can absorb and regulates the current to match.

Glass, I checked out your jeep (looks great) but I have to ask...did your dash grills have anything behind them stock? My '93 ZJ had all stock stuff in it (not the premium sound) and those grills had nothing behind them. I put my tweets there too and sounded great but I can't help but wonder what Jeep put there in the higher end stock systems. Was it just a tweeter or was it a small fullrange? Just curious...
 

New member
Username: Glasswolf

Post Number: 593
Registered: 12-2003
that spot was for the tweeters on the Infinity setup they offered, but yeah mine was empty as well when I removed those grilles.
made a great spot for the tweeters though! hehe
good imaging as well.
 

New member
Username: Santaclaw

Post Number: 11
Registered: 01-2004
Sonds like a good setup there GlasWolf..

You almost "can't" fail if you use high quality equipment like you have, but then again annything is posible, the impossible just takes a little longer.. heh :-)

Don't your amps get afully hot under the rear seat with so little space ???

Built in hemroid coocker:-)

I had both my tweeters built into my A "beam" or the rollcage that starts by the lower corner of the windshield, (don't worry, I only cut plastic, not the acctual a-frame).

Due to a sirious lack of space, I HAD to put my "front set" amplifyer inside of the dash board. Causing all kinds of heat problems, I had to put a 120 mm fan on each end of the amplifyer to avoid clipping....


Tweeters : http://www.maaudio.com/images/1700/1690.jpg

1.5" :-)

100w rms, 200w max, makes a LOT of noise, and manages to compensate for the two strokers at low volumes...

Mid range prooved to be a pain in the but, cus the sub woofers kinda blew the midrange elements in seconds... in the rear of the car, i got a local car stereo shop to build me 2x 6x9" boxes outa carbon fiber, it may not be the best suited material, but it looks great, and it stops my infinity kappas from burning out again..
(happend 3 !! times before, but only once before with my kappas, 2 of the times was with cerwin vega HED 6x9")

Still my kappas move quite a bit when i turn up the volume...

the same can be said about my front mid range speakers, 6.5" from Phoenix gold, but for some strange reason iv'e had em for 4 years, and still they sound like the day i baught them...


To get room for my batteries, i had to wack the spare tire well flat, and remove the bracket there, then I sanded the whole thing down, and repaintede it, before adding a layer of thick "see throgh" tectyle, + 3-4 cas of noise killer, before I constructed a battery holder for my stingers, this I made out of mdf and black fabric, since both my main amplifyers are more than 0.6 meters in lenght, fitting them both also was an issue..

But I did it the only way possible, by mounting one in the rear seat, (can be tilted forwards for xtra sound pressure... heh..)
And one tilted towards the back seat, so that both the hc 4002's face backwards, i also built a mdf/gray fabric structure to "fill in" the emty spaces around the amplifyers..

The capacitors are quite huge,

http://www.maaudio.com/images/1700/1682.jpg

And the only place i HAD room for them was inside the rear wheel arches..

And that ment cutting the inner wheel arches, (these have no function beyond making the trunk look sqwere instead of round), after spending a good deal of money on dampening mats, i cut off what i could, unfortunatly on the right side the tube for the gas filler cap, was kinda in my way, so I had less space to work in..

Annyway, I coverd everything with dampening mats, and built 4 MDF boxes to hold the caps, and hooked them up in paralell..

(With two on each side of the trunk i have a massive 60 fharad's in total... heh..)

I found place for the 30 channal equaliser on the left side of the trunk, so it's easely accessable, but the dumb thing is, that now the phono cables for the front amplifyer, that drives both my kappas, the tweeters, and the 6.5" phoenix gold speakers, need to go from the head unit, to the equaliser, and then to the front..

That's 3 pairs of phono cabel to the back (including the calbes for the main amplifyers), and six pairs to the front.

Btw, I used stinger phonocables...

I also has a "bass driver" placed 3" from the head unit, that controlls the two main amplifyers..

All in all i guess placing the front amplifyer was the most difficult bit..


All i need now is a bit more power, and a new HEAD unit, as it's a 250$ JVC unit... hehe...
 

New member
Username: Santaclaw

Post Number: 12
Registered: 01-2004
Sorry, i ment GlassWolf...
 

New member
Username: Glasswolf

Post Number: 598
Registered: 12-2003
the 2125SX gets extremely hot, but I have two 8cm fans next to it to pull air across the amp which helps.
plus I don't have anyone in the back very often anyway. There's a lot of space under the rear seats of a Jeep. It's essentially built there as storage space.

 

New member
Username: Motoman22

Post Number: 65
Registered: 12-2003
The storage under the rear seat is extremely handy in that ZJ. The front 'wall' of the area, where the seat hinges forward, is easily cut with a couple of intake fans on one side and a couple of exhaust fans on the other.

My 5002 shut down on me before I put the fans in but we all know it's a hot runner. Still, really neat nook. I miss my Jeep /c:
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