Multiple alternators?

**Psychobiker** · 07-29-2005, 06:10 PM

Hi,

Either my battery in my RR has gone phut or my alternator. I'll try replacing the battery, and even if that is the problem, would two alternators be a good idea? Can you feed two into one battery or would it be best to have one batt for system and one for the car?

L

**markland556** · 07-29-2005, 06:34 PM

doubt you will need 2 alternators, there are high output alternators that iv seen go up to 500 watts. and that is crazy overkill, dual batteries is a good idea, just look into a tank circuit.

**anitanium** · 07-29-2005, 08:00 PM

dual alternators won't really help unless you are running a crazy setup that requires it...
my 100amp powers my amp, screen, 300W inverter just fine
even cranks with them still running

**Psychobiker** · 07-29-2005, 08:36 PM

If my stock alt is dying..then I'l change it for about 200A, as I'm running a JBL 1201.1, 75.2 and the 300w inverter....

**lexanite** · 07-29-2005, 10:29 PM

Originally Posted by anitanium

dual alternators won't really help unless you are running a crazy setup that requires it...
my 100amp powers my amp, screen, 300W inverter just fine
even cranks with them still running

Where did you put your 100Ah? Thanks

**Nic** · 07-29-2005, 10:51 PM

Originally Posted by markland556

doubt you will need 2 alternators, there are high output alternators that iv seen go up to 500 watts. and that is crazy overkill, dual batteries is a good idea, just look into a tank circuit.

you mean 500 amps? 500w is only about 35 amps at 14v

**Cheekz185** · 07-29-2005, 11:29 PM

I never understood putting 2 batteries into the car for less drain on your alty? I mean if you think about it now the alternator has to charge 2 batteries. How is this a gain?

**lexanite** · 07-30-2005, 12:54 AM

One (original) alternator charging 2 batteries will be hard to survive especialy just after cranking (if connected parallel). Find the alternator spec for sure.
For 2 batteries better use two alternator at two seperate circuits as Psychobiker said. Its might be the best way.
As long as there are enough space ofcourse.
SPL mania did that.
Replace the orig alt with a bigger one (for 2 parallel connected batteries ) also possible to do.

**turbocad6** · 07-30-2005, 01:26 AM

batterys are for storage of energy.... even if you have large peaks of demand...the majority of the time the alternator will put out more than is used & will add to the storage capacity....think of the altenator as a trickling water hose & the battery as a cup... if the battery is only a half pint...thats the most reserve you will have at any given moment.... any extra flow from the hose can't be captured..... same sinario with two gallon buckets.... sure it may take longer for the trickling hose to fill them, but you will have a large supply of water backed up when the demand is there.... get it?