my light are dimming and i think they shouldnt be

[markak134 1]

also if i turn the music up to loud the volts drop way to much and my amp will go into protect

i have a 250 amp alternator and a optima redtop under the hood and 2 deka intimidators in the trunk and a sundown 3000d im guessing the problem is the red top what do you guys think

[shizzzon 461]

disconnect all 3 batteries and measure voltage about 2hrs after u disconnect them. If any of them read below ~12.7v, they need to be put on a charger one at a time.

[Sir-Lancelot 216]

check your grounds and gains.

What impedance are you wired to?

[helotaxi 46]

How are your grounds set up?

[markak134 1]

1ohm load for the subs and the ground are like this

[markak134 1]

i check the voltage on the dekas i didnt disconect them its 12.3

[Sir-Lancelot 216]

i check the voltage on the dekas i didnt disconect them its 12.3

Try to charge it up on a charger and see if you can get it to hold a charge. That's too low!

[Julian 641]

Wayyyyyy to low!

IIRC my dekas are around 12.7~

[shizzzon 461]

you have at least one batt in the bunch that needs charging asap, not from an alternator either.

Sears has a microprocessor charger for around $90 that is used to charge AGM batts.

the specs are 2A trickle, 15A slow, 40A fast, 120A jump.

If you do not fix this soon.. this can result in more than just your batt(s) eventually dying... your alternator will be next.

[smashedz28 110]

you have at least one batt in the bunch that needs charging asap, not from an alternator either.

Sears has a microprocessor charger for around $90 that is used to charge AGM batts.

the specs are 2A trickle, 15A slow, 40A fast, 120A jump.

If you do not fix this soon.. this can result in more than just your batt(s) eventually dying... your alternator will be next.

can you explain this? why not an alternator, dont alternators put out the same as a battery charger?

[jcarter1885 995]

When you have a that many batteries draining, you will need more than an alternator to keep them charged without straining your alternator over time and maybe even killing it.

Alternators arent made to charge a lot of batteries.

[Shogen 325]

But why would it matter if the charger does it separately??? Will the charger put the batteries above his stated resting voltages? And then putting it in the car will maintain it???? I'm just confused about it...

[markak134 1]

would a battery isolator help

so is the way i have the batteries hooked up right or do i need to change the grounds also yea wen i charge it i wonder how long they will stay up maybe i need a better alternator

maybe its messing up cause i have the red top and 2 dekas maybe i should ditch the redtop cause its not the same kind of battery maybe thats why they arent charging right

Edited January 9, 2011 by markak134

[smashedz28 110]

When you have a that many batteries draining, you will need more than an alternator to keep them charged without straining your alternator over time and maybe even killing it.

Alternators arent made to charge a lot of batteries.

another question.. wouldnt a 250a alternator be able to handle a few battery's better than a stock one? he said he has a 250a

im very curious about this topic as well. sorry for thread jacking into this one lol.

[shizzzon 461]

an alternator is NOT designed to replace a charger.

An alternator is designed to be used in cyclic operations, not continuous use.

Alternators produce a LOT of heat at the bridge rectifier where it converts AC over to ~DC.

The amount of discharge the batteries are currently in will more than likely make the alternator work at full output.

The longer it's maxed out, the more heat is generated.

Too much heat, the diode(s) on the rectifier can\will burn out causing the alt to lose it's output rating by 33%, then 67%, then 100%.

Rectifier is common area of alternator failure, that's why i gave that as example.

there is only one alternator line that i know of that is built to withstand abuse from heat and that is DC XP line, but that isn't on topic.

An alternator is used to MAINTAIN the batteries charged rate. It can recharge batts up as long as it doesn't overwork the alternator.

Group 31batts such as a 9A31 Deka is a pretty big battery for any alternator so 3 of them is ridiculous on a single alternator.

Think of a can of coke and an empty glass-

An alternator is like filling that coke up in the glass. The fizz will settle down and the amount of coke in the glass will appear to have went down...

A battery charger is like pouring the coke in the glass slowly. The fizz is not a factor because you know that once you get to the top, it's filled.

that's the difference in how an alternator and a battery charger works in terms of CHARGING.

Batteries are HIGHLY suggested to be fully charged before installing an alternator. If not, the battery will never be at it's highest charge level.

Using batteries in discharged states will kill them quickly.

[shizzzon 461]

also, you should get rid of the red top and replace with the same battery as what's in the back.

If you cannot, a solenoid will be your other option, not isolator.

Many people will say they run mixed models of batts without problems...

Sure this can be possible but if i were to layout what is actually happening, you will see that the user will not get the full possible life out of his\her batteries by mismatching batteries.

[smashedz28 110]

good info, thanks shizz

[Sir-Lancelot 216]

A slow trickle charge conditions the battery to hold charge, your alt is going to attempt to charge them all at a very rapid rate.

A slow charge is a much deeper charge.

OP you dont need an isolator.

[markak134 1]

im not sure if my alternator is that good because if you look at the dc power alts they are like $500 and i got my 250 amp alt on ebay for $100 somthing they guy assured me its 250 amp but nothing on the box said it and it was made by world power systems or somthing maybe its garbage

should i take one of the batteries out maybe i have to many

Edited January 9, 2011 by markak134

[shizzzon 461]

i would assume is was rewound...

If i am right, at idle, it will do jsut enough power to prob run the vehicle and that's almost it.

Because of this, ANY amount of volume in use when your car is at idle will cause the load your amps are pulling to be straight from the batteries, not the alternator.

Now, i can't say how close your alt is to rated power when the car is revved to or over 2,000rpm but for less than $200, you'd be lucky if it does over 140A max.

What state you live in, btw?

[markak134 1]

i live in pennsylvania

[shizzzon 461]

oh, i dont know anybody there, i know someone in connecticut..

Was gonna send you to a place where one of us, members, could help you look over your vehicle, but nvm.

[markak134 1]

what if a add another ground for the back batteries will that do anything

[shizzzon 461]

nothing will help except charging your batts individually first.

You will need to measure your red top too disconnected.

[markak134 1]

i checked the redtop its 12.4v i didnt disconect it tho

i could charge the 2 rear batts tonight but i dont want to disconnect the redtop tonight

my car is retarded i dont have a jack and u need to take the wheel off to replace the under the hood battery

Edited January 9, 2011 by markak134