alternator charging fluctuations

These alternators have a delay as well, most times it's 10 seconds before the regulator reacts.

Oh and the voltage regulators are set to 14.7 volts. All the "alternator booster" does is put a diode on the external sense wire. The sense wire tells the regulator the system's voltage so it can adjust accordingly. Putting the diode drops that reading by 0.7v so it tricks the regulator into putting out more voltage. Also, I know the EBTCM has a code for over voltage, IIRC the voltage cap is 14.8v or so...so you take a regulator set for 14.7 volts and trick it to put out more voltage. If your grounds and the rest of your connections are healthy, you'll be throwing a code.

Quote:

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Originally Posted by ITHURTZ

operates in oem target all day, until i slam hard, then 11:)

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Then you have other problems, mainly connection based, and probably internal problems with your alternator. The voltage boosters are a gimmick that falls in the same category as removing the honeycomb screen from your TB, and adjusting your BBV. Might as well put a resistor on your IAT while you are at it. Look up how these alternators work and you'll see.

lol I assure you my electrical system is in tip top above factory shape. I did remove the oem honey comb to, and like the electrical system, went bigger.

If everything is in tip top shape why do you need the voltage booster? It's a band-aid fix at best.

Just in case he wants to use an eBay electric supercharger....

Because high voltage roller

Your voltage regulator is set at 14.7v, if everything was working correctly that would be your optimum voltage. You yourself said you had to use a voltage booster to achieve that...

It's simple mathematics, you are lowering the amperage by increasing the voltage. Not trying to sound like a dick, but I thought you were smarter than this.

You are looking way to hard into this, the original statement the op said was it would sit high 12's at some point which is normal. I am not normal, and that isnt acceptable to me, I prefer high 13's mid 14's at all times. I didnt do it for a bandaid fix, to fix a failing alt (its not old), I did it for my visual pleasure, mid 14's check, windows go up faster check, happy camper.

Mid 14s is a healthy alternator with good connections. You don't have that, and neither does the OP. Something is wrong with both of your charging systems.

they dont stay at a constant mid 14 forever, I dont like fluctuation.

What you are doing has no effect on fluctuation, it simply moves the area of fluctuation into dangerous areas for the car's electronics. You need more amperage to fight voltage fluctuation, or at least a regulator with a lower delay (2.5 seconds is the lowest I've seen).

Whats the stock delay? Link to other regulators?

10 seconds. http://store.alternatorparts.com/cs1...egulators.aspx

Ebay has them too. They call the delay Load Response Control.

I think you guys both missed the point. The charging system is working fine on the OP's car and everyone else's here. It is designed to fluctuate with load.

in a DC system higher voltage does not mean lower current. The loads are fixed and as voltage goes up so does current.

Example: a relay coil has a resistance of 350 ohms and has 12V on it the load is .034 Amps or 34 mA
if you increase the voltage to 14.4 then the current is .041 A or 41 mA.

lets say a fan motor running draws 35 amps at 12V the same motor will draw 42 Amps at 14.4V

Jeff

The thing is the alternator has to produce that added amperage at the same RPM, that's why the amperage output drops, the voltage goes up.

No, if current outstrips the alternators ability to output the required voltage the voltage will sag. The alternator pcm/regulator will respond by increasing field current to raise the voltage back to where it needs to be.

Basically the system is designed to produce only what it needs.
Jeff

From my understanding, alternators are only capable of so many watts at a certain RPM. When the the the amperage needs exceed what the alternator is capable of, ohm's law state the voltage must drop (to bring the amperage up). The voltage booster does the opposite of that, takes the voltage up so the amperage must go down (at least the maximum amperage output at one specific RPM).

Everything you're describing is normal except it going down to 12.80 while in motion. I would guess that means you've messed it up. Get the CS144. You won't have to worry about it again.

That's true to a point, that's why a lot of people burn up alternators because of running too much power at low rpm and saturating the field. We don't typically idle around so the alternators RPMs at cruise are in its efficiency area so there's no point in having all this power unless you are just idling around all day. I run in half in town and half freeway and what the alternator can't supply it takes from the battery like on fan startup. The alternator can easily replenish this.


Jeff

Quote:

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Originally Posted by chrsmi1

Everything you're describing is normal except it going down to 12.80 while in motion. I would guess that means you've messed it up. Get the CS144. You won't have to worry about it again.

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I'm telling you this is normal for anything past 04+ I have been driving rentals for more years than I care to discuss. I have driven an 05' just like the one I own when it had 5k on it and that one did the same thing. Exactly as the OP described. I have driven cars and watched the voltage stay at 12.5 going down the freeway for hours. I kick on the lights, rr defroster, and AC and the voltage would rise to the mid 13's coming to a stop where the fans kick on and it went to 14 and change. This is normal.

If the OP wants to upgrade or make the modification then cool, but telling him there is a problem is incorrect.

Jeff