I need more current, capacitors failed:(

[DIGIDIGIBOMBO 10+ year member]

Hi, lets assume my battery is 50 ampere-hour, and i have a load of 20amperes( lights...) the alternator should at least provide (50+20)/3=23.33amperes? many people tole me i must add the total load and alt must provide at leat 1/3 of the load. In some site they say: charging rate is between C/10 and C/20, C is the ampere-hour capacity of the battery and they didnt mention the load( lights, AC,...) of the car. I tried a 1farrad monster capacitor, no results, if a resistance needs 2 A, even if the source can pump 10000 A, my load will only use the 2A it tont fry...but what about batteries? even if i install a 200A alt, why would it fry a small battery since the battery will only use the ampere that it needs.? Thx

Click to read more...

 

[qtipextra 5,000+ posts]

We could have told you a capacitor would have failed. A capacitor is to store energy, NOT PROVIDE AMPERAGE! The alternator PROVIDES amperage. Bfore you try to store power, make sure you can SUPPLY power.

It wont fry your batter to upgrade to a bigger alt. Thats what you need to do. 200 AMP alt would be great. Also, do big 3. Then upgrade yor battery.

 

[DIGIDIGIBOMBO 10+ year member]

Well i have a monitor in my car and on the bass, boum the monitor light is dimming a lot i dont want it to fry out man. i want to get rid of this voltage drop, by having more current ( juice), when the load needs too much current more than what the source can provide, this will result into a voltage drop. i used a DMM and the voltage droped to about 11.3V thats not too much i know but the monitor is dimming a lotttttttttt. On many sites they said charhing the battery too fast....might fry it....i already did the big 3 and it helped a lot.Plz some answers about (battery AH+load ah)/3, and about charging battery too fast will cause it to heat a lot....and explode....?

lets assume my battery is 50 ampere-hour, and i have a load of 20amperes( lights...) the alternator should at least provide (50+20)/3=23.33amperes? true?

Thx a lot guys

 

[qtipextra 5,000+ posts]

Okay.

1st: Forget your little formula. PERIOD.

2nd: The only thing that matters (in your case) on the battery specs is the CCA. This is how much amperage you can draw for 5 seconds in cold weather before the battery will be below 10v. (Without your car running.)

3rd: If you have voltage drops, it's because your charging system (your altenator) can not supply all the "juice" that your system is asking for. To compensate for the amperage loss, it drops the voltage.

4th: A chagring system only puts out that much amperage when you need at that moment. (Like when you crank it.) Other times, it will only supply what your electrical system is requiring. So, if you have your headlights on, your AC, and your system on low, then (Purley an estimate), say, about 80 AMPS. A 200 amp alt will only be providing 80 amps at this time. Now, a godd song comes on, you crank it up! More power=more amperage draw. So, now you need 190 AMPS (Again, estimate). Your 200 amp alt will still be able to provide you that amperage, and your voltage will not drop because of it.

5th: The battery will pull an amount current from your alt until it is charged. This rate is determined by your battery status, and your alt will only supply the amperage to your battery that it needs to charge it, and so it doesnt "fry".

6th: The amount of current is determined by each component in an electrical system. Each component draws its own amount of current. The current form your alt will be distributed as such.

7th: The alt is what provides the amperage when your car is running. Your battery and alt dont work together when your car is running.

So, when your car is running, you need to have a good alternator. Make sure you can provide the amperage your system needs. And no, it will not hurt your battery.

Hope this helps.

Shaun

 

[thch 10+ year member]

note that amp-hours is not the same as amps. just like kWh (energy) isn't the same as kW (power).

 

[DIGIDIGIBOMBO 10+ year member]

Thx guys, thats what i though was true, battery will **** the amps it needs, so it ont fry. But i used to use some Battery chargers in my house and there is a button where i can increase the ampere....to pick a fast or low charging rate, and they always recomended the low rate. Whats the difference netween Ampere hours and ampere, 12 ampere hour battery means i can **** 12 ampere for one hour and the battery will be empty. If a simple load needs 50 ampere they mean it will **** 50 ampere per hour from the battery, so in two hours it will **** 100 amperes from the battery right? and a 200 ampere alt means it can provide 200ampere at all times or in one hour for the batt? Thx again

 

[arsonbob 10+ year member]

DROP THE HOUR STUFF. Sheesh. It's a on factor. Google amp/hour and amps.