[HWYSTR455]

This is a little new to me, hopefully someone has some experience here. My stereo for years cooks altenators, and have gone through a ton of them (have a alt graveyard to prove it!). I tried every kick-butt alt on the market, asked a gazillion questions regarding, and just kept cooking them. I have everything wired properly, overkill as a matter of fact, and it's all correct gauge wire, connections, relays, blah-blah-blah. (see attached pics) Out of the blue, was at a shop that also did custom stereo installs, and the guy said, " ...and you keep cooking alts, right!?!". Uh, yeah! He said I need caps, which prevents pulses on the internal regulators, and kills them. Ok, so, I did the homework, and bought a pair of Tsunami 1.2 farad caps and installed them. I've been running on a cheesy standby alt now for like 2 months, so guess there's some truth to it! Glad I figured that one out, since carrying a spare alt and belts was getting to be a pain!

Anyway, question is, I tossed the thing on a charger while I was putzing around in the garage, and the darn thing never goes below 1.6a. It's been on for like 4 hours now, and it's flipping between 1.6 and 1.7a, and yes, the battery is good. Is this normal? The cap indicators show 14.7 by the way...


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[george kujanski]

What "thing" did you put on the charger? If you are charging the battery, a fully charged battery will easily draw an amp or two even when fully charged.

George

[HWYSTR455]

Heh-heh! George, not going to talk about my 'thing' on the forums! (Just kidding!) I put the charger on the battery, and it's an 'intelligent' digital charger, one that usually will go to like .2 or zero normally. Unless there's a load, it should go to almost zero, and not even the memory on the stereo head unit draws enough to show usually. And everything else is like 'off', because of the way I have everything relayed. Like I said, it's weird, because it usually does go to zero. And yes, I 'charged' the caps properly on install, these are 'intelligent' caps with a built in 'load' to properly charge them on install. I'm tempted to disconnect the battree, leave it on the charger, just to see if it actually DOES go to zero, just to see if this is 'normal'. You ever seen this?


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[HWYSTR455]

Darn, the battery just went into a fault code (FO3). Guess the battery does have a bad cell. Stupid optimas. The F03 fault code in the charger manual means the battery won't fully charge. The charger manual says that the battery is 'sulfated'. What the heck does that mean? How can that apply to a dry-cell battery? Maybe that's the way it will act (the charger) with caps? This optima is like maybe 7 months old....


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[george kujanski]

Did it act like this recently without the caps?

I'm not familiar with these caps, but if they have an internal load, that's what may be causing your charger to act differently. If they have an internal resistive load, that will draw some current and may be what you are seeing.

Does your car start ok or does it crank more slowly after a short cranking time?

I don't know why a 7 mo battery would be defective (or sulfated); I would suspect the charger is too "smart" for it's own good and giving a false indication.

Capacitors that large may very well have an internal load to discharge the cap when power is off. The load bleeds off the charge to make it safe to handle if the cap were to be disconnected. Accidentally connecting a piece of metal like a paper clip across the terminals if charged could very well melt the paper clip.

George

["QUICK-SILVER"]

Was the fault reading with or without the cables connected?

If it was with I'd start all over with them off.

[guccieng]

i don't think optimas are dry cell batteries; they just use a gel that evaporates slower when hot, instead of water in the regular lead-acid types. the bad thing about the optimas is that when the gel does evaporate, you can't replace it. perhaps you put the battery under so much stress with the stereo (when you didn't have the caps) that the high-amp alternators were essentially 'cooking' the gel in optima during fast charging.

[66Mutt]

I found this yesterday when I was looking for something regarding wiring.

Ideally, you should opt for a high-output alternator and additional batteries. A good rule of thumb is to use the largest alternator you can fit on the engine and an additional battery for every 500 watts of amplification

This may be basic stuff to you car audio nuts, but the last time I had really installed stereos in cars was 25 to 30 years ago. Full article is here, the article addresses the amp load that a big system puts on the alternator.
http://www.termpro.com/articles/electsys.html
Doug

[HWYSTR455]

George - Not sure, didn't try tossing the charger on there prior to installing the caps, and had cooked like 3 alts on this battery. So guess it's possible that the batt may have been an issue before. It starts ok and everything, but honestly, I've had issues with every Optima I've used. They're very sensitive to shorts, and the cooked alts may have caused a cell or two to go bad.

Quick-Silver - Fault code was with the caps connected, and was thinking of trying charging with them disconnected. Kind of had the same line of thought there.

Guccieng- Dry cell. http://www.optimabatteries.com.au/# , and yes, something along the lines of cooking them with the load.

66Mutt - I usually run at least a 105a alt, have run up to a 200, but anything over 140 with a v-belt will pretty much slip under load. (Search my other posts on the subject). I've also when shopping for alts always look for good low-rpm output, like what's used on police and ambulances. Adding a second battery usually only helps when the alt can't keep up, or for periods of running without the alt running. Thanks for the article, will check that out!


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[guccieng]

oh, i see. they call it 'dry' even though it's a gel. i figured that would be called 'wet'.

[johnsma22]

I've had an Optima Yellow in my car with a 100 amp alternator, one 300 watt 4 channel amp and one 500 watt mono amp for the subs with a 5 farad cap for about three years now with no issues. I only needed the cap for the sub amp. Before the cap I could see my electrical system pulsating along with the bass beat, LOL!

The Optima Yellow is what is recommended it you are running a powerful audio system. It is a true dual-purpose battery, with high cranking power and the deep cycling needed for the demands of a high end audio system. I've never even taken the thing out of my car for the winter. I only disconnect the negative terminal. It's always been right there when I reconnect it in the spring.

I did have an issue last year of finding it dead after the car sat for a few days. I traced the problem to my glove compartment light not turning off when I closed the door. It was just a faulty switch. Took care of that and the battery took a 100 amp "start" charge from my charger and then charged fully via the alternator after a nice long drive. No problems since. Your amps need a REALLY good ground as well to avoid nuisance problems.

[george kujanski]

If I remember correctly, Optimas are gelled-electrolyte, spiral-cell batteries, not really "dry".

I'm thinking the alt failure mode may not necessarily be "frying", but with high power audio amps, the transient nature of the load may somehow damage, or confuse the regulator in the alt, such that the output voltage fluctuates too much. If the voltage goes up, the alt output current could also, causing additional internal heat, more than the fan could remove, (depending on engine rpm).

If so, the additional caps at the audio amp will help filter the current transients so the alt regulator doesn't see the transients, stabilizing the output. The additional caps are a good idea.

George

[HWYSTR455]

The gel is absorbed by fiberglass mat, which becomes 'dry'. So, it's a hybrid really, but it does use a gel, so it's not 'wet'. Wet refers to acid, basically.

As I said before, Optimas are very susceptable to shorts. Even a momentary arc kills a cell (or more), which could be what a toasting alt did for the one cell I suspect is dead now.

George - That's kind of how that was explained to me, the 'pulsing' is somehow toasting the regulators, though not sure if it was related to heat.

johnsma22 - Yup, grounds, power, and the type of cable is critical. I ran 0 ga fine strand for ground and power back to the trunk, with several junction posts along the way. The one junction post for ground in the trunk is actually on the support brace for the trunk lid hinge, and that goes to the post on the amp board. I could have used a fatter cable, like a pair of 0 ga cables from the battery back, both pos & neg, but didn't see the point. The cables never get hot, even when 'taxing' them for periods of time.

Like I said too, I run good alts, and have tried them all. Now with the caps, I'm about to get another, and am open to suggestions. I figure a 105 would probably be fine, though don't want to go over 140a.


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[66Mutt]

Just how big is your system in watts?
I know the generators that I have run in the oil patch don't run well with fluctuating loads as stand alone systems. The tail kind of wags the dog while chasing the load. Capacitors help, but what really helps is when you have the luxurty to tie into the utility's system. No you have a little tail trying to wag a big dog. Similar effect is achieved on the automobile with multiple batteries. With the stabilized load and frequency, I was able to run the generators at higher loadings than in the stand alone system.
Doug

[HWYSTR455]

It's like 600 watts, but that's rated at 12v. At 13.8, think it's closer to 1000. I'm not willing to add a second battery, mounting is the issue for me.....


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[stellar]

AGM (absorbed glass material) batteries Mostly for spiral cell design and antique script batteries. Quality-questionable ( my opinion), but great for special needs no leaks no gas great for inside of car, easy to ship. Expensive. You can get 2 big conventional batteries for the price of one AGM. But like the wife says, size matters.
When the base kicks in voltage drops big time, just watch your lights. Caps are the best solution for this. They will supply an instant surge when needed. An alt can't do that. The voltreg senses the voltage and if low, allows an increase in field strength. By the time it senses low volts and reacts and power is increased it is to late.
You need a large power source for the sound system to draw from and allow the alt to charge the battery.
If you put in a larger winding into the alt to increase the output, Say to make a 105 amp alt into a 140 amp alt , the low speed out put will decrease but the alt will put out more at high RPM. In other words if you are driving down the interstate, the high output alt is fine, but if you are like most people the stereo is being used mostly when the car is at low RPM bee-bopping around town.
So the best way to do it is add a large battery and caps using a stock alt. By stock alt I mean an alt designed for a specific output. If you need 140 amp alt, don't alter a 10SI 12SI or a CS130 to do the job. Use a CS144. But again size matters. The CS 144 is a true workhorse. It can be upgraded to 200 amps with little change in low speed putput Since you can't add a battery I suggest you try to find a way to mount a CS144.

[HJones1313]

FYI, I've seen Optimas test "bad" before, but I've seen 'em come back from the dead after 4 or 5 days on a trickle charge. As far as power goes, I run 1700 watts, using a Optima red for the car, yellow Optima for the sounds and a 1 farad cap connected to the sub amp only. Batteries are isolated via solenoid, using a Powermaster 140A one-wire alt.

[HWYSTR455]

Well, looks like the spare alt I've been using is going bad, so not sure how much the caps helped. I'll toss a new one on, and see if that lasts. If it goes toast, guess I'll have no choice but to add a second battery.


HJones1313- The Optima I have 'works', but I'm guessing it has a bad cell. It charges, shows good output, holding, and even sits and holds for a couple days. But, it does still have a bad cell, and it should probably be replaced. Tell me about the solenoid / isolator you have for your second battery?


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[HJones1313]

Dont trust the charger. The solenoid is readily available at most high-end car audio stores. The one I like to use is made by Fosgate. Heres a pic.

[HWYSTR455]

And the stereo remote on kicks the sol on?


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