Dual alternator solution?

Pedi · Post by **Pedi** » Sat Dec 01, 2007 6:56 am

As for my install, I have bought an 300A alternator to charge the audio-parts, as the carstereo has it's own 12v system.

BUT...

I think maybe the 300A might not be enough. So I was playing with the thought of mounting another 300A alternator in parallell.

Anyone done that before?

Is it "just" to mount 2 similar alternators (with identical regulators) in parallell ??

I have never thought about this solution before, so I wonder if it is possible...

brutux · Post by **brutux** » Sat Dec 01, 2007 9:38 am

I'm not sure what the effect would be in parallel; wouldn't there need to be some sort of isolator to regulate voltage? There are kits available for doing a dual alternator set up (like one I found here for limo's) and they would probably have the answer. Keep in mind running another pulley off the belt will rob around 5-10 hp which may or may not be a consideration for you. Do you have the room to run two seperate systems (alternators & batteries) and have each power half the system? That might ultimately be easier than trying to run two alternators on one electrical system.

Pedi · Post by **Pedi** » Sat Dec 01, 2007 10:03 am

I do have place for seperate systems, including all batteries and 3 alternators (1 for original system, and 2 for car stereo).

My only Q is how to use 2 alternators in same system?

If I loose 50hps, I do not care, my car is for Phoenix purpose only

I love Amperage, hehe...

1moreamp · Post by **1moreamp** » Sat Dec 01, 2007 10:10 am

Some years ago I saw a low rider with 5 alternators being driven off a hydraulic pump motor that was being driven off of one battery. So you might look at a non motor driven system to supply power that is not engine speed controlled....Just a though as if you need the amperes your talking about I would think engine speed would be a issue somewhere along the line of thinking. And a independent drive system is not so far fetched as not to be practical....C

Pedi · Post by **Pedi** » Sat Dec 01, 2007 10:49 am

Yeah, that might be a solution, C - infact a good one. But as I am a mechanic, that is not my problem. I can build whatever it takes in metal, but I wonder how it will work with 2 identical alternators in parallell - eletrically speaking...

1moreamp · Post by **1moreamp** » Sat Dec 01, 2007 11:13 am

I would think that as long as they both produce the exact same output voltage that there will be little issue. The cables used to connect the alternators together should be the exact same electrical length < I.E. The exact same length, and DC resistance each to the main power block that will combine there outputs together>

This sort like stacking DC power supplies in its application. or stacking Class D amps also.

Bridging two amps thru a load is called "bridging" "Stacking is where both the outputs are combined at the load.
Stacking and bridging are different and have different issues to be dealt with to make them work correctly.

Your trying to "Stack" the outputs so they will evenly share the load. A simple way is to make sure both alternators see a given resistive value directly at their outputs that combine after this given load so both alternators see a common value load to the output block connection to your amps.

You can also run separate power systems to your amps where group A amps get powered by alternator A and the sane fro Group B and so on ...

I like the idea of using a low rider hydraulic pump and motor to drive the alternators as your charging system can be isolated from engine speed. In fact you can run and charge your system without bthe engine even being on at all...just a thought as your going to the show and running your car might get smelly from exhaust fumes...C

Pedi · Post by **Pedi** » Sat Dec 01, 2007 11:20 am

C...

Thank you for the info about stack and bridge. I am so impressed with all the knownledge you have...

nico boom · Post by **nico boom** » Sat Dec 01, 2007 12:49 pm

Ivar; I can send you a schematic diagram of the mercedes 600 pullmann.
It has 2 alternators charging one battery.
Also another thing; to get 14 volts instead of 12, I once saw a [spl] car with 7 cells of 2 volts [ from a electric lifting-car-thing[?].
Worked very well, deep cycle battery's,in combination with some caps.

Post by **Wakeup** » Sat Dec 01, 2007 12:52 pm

http://www.stevemeadedesigns.com/board/ ... opic=11015

I know nothing about cars...but steve meade....pretty famous if you dont know who he is....
did that.

nico boom · Post by **nico boom** » Sat Dec 01, 2007 1:08 pm

NICE...... and

Every true spl- lover should have these!
And a big-block to be able to still drive on the highway

Post by **Wakeup** » Sat Dec 01, 2007 1:37 pm

Ya totally..and he poweder coated his black....looks sweet in black.

dedlyjedly · Post by **dedlyjedly** » Sat Dec 01, 2007 3:03 pm

Just shooting from the hip here, but what about an external regulator that's designed to run both alternators? Is that feasible?

1moreamp · Post by **1moreamp** » Sat Dec 01, 2007 4:08 pm

That would work also, BUT most modern alternators are IRA type Internal Regulated Alternator

You would need old school alternators and a single regulator that would control all the field voltages, But its very possible...

Pedi · Post by **Pedi** » Sat Dec 01, 2007 4:29 pm

1moreamp wrote:That would work also, BUT most modern alternators are IRA type Internal Regulated Alternator

You would need old school alternators and a single regulator that would control all the field voltages, But its very possible...

For one times sake, C, I do not agree with you.

To be honest, that is not correct on THIS side of the big sea.

Here most alternators in cars are Bosch and Valeo-type, with seperate regulator. Japaneeze and US-alternators are much alike, "all" with IRA-type...

So in MY install, I hope to use a common external regulator, with elecronics going to the brushes on each alternator....

theburb · Post by **theburb** » Sat Dec 01, 2007 4:48 pm

why do you feel you need more than the 300amp alt....just wondering

Pedi · Post by **Pedi** » Sat Dec 01, 2007 4:52 pm

Because the number of my amplifiers does consume Ampere heavily, like a hungry wolf...

And it is better to have way to many Amperes, than way to few...

1moreamp · Post by **1moreamp** » Sat Dec 01, 2007 5:25 pm

Pedi wrote:
1moreamp wrote:That would work also, BUT most modern alternators are IRA type Internal Regulated Alternator

You would need old school alternators and a single regulator that would control all the field voltages, But its very possible...
For one times sake, C, I do not agree with you.

To be honest, that is not correct on THIS side of the big sea.

Here most alternators in cars are Bosch and Valeo-type, with seperate regulator. Japaneeze and US-alternators are much alike, "all" with IRA-type...

So in MY install, I hope to use a common external regulator, with elecronics going to the brushes on each alternator....

No worries .....You can still buy old style alternators here also, but they are not so common place anymore, The IRA type pretty much rules over this way nowadays. The Electronic controls seem to give Detroit what they wanted.

Oh a typical field control wire will need as much as 7 amps to operate the alternator correctly, so you might want to look at that number when daisy chaining control lines to each of your alternators. Ford and Chevy used to use a simple voltage controlled relay on their old systems, perhaps you can do the same with yours.

Oh and don't forget the higher speed pulleys so you Alternators push at idle also. My speed up pulley gave me almost 110 amps at idle RPM. Sort of removed my need for a big cap, I still use a 2 farad though just for good measure...LMK how your setup works out...C

dedlyjedly · Post by **dedlyjedly** » Sat Dec 01, 2007 9:47 pm

A lot of the after-market alternator companies like Ohio Generator, Iraggi, and Wrangler NW have models available with external regulators.

theburb · Post by **theburb** » Sat Dec 01, 2007 11:03 pm

Pedi wrote:Because the number of my amplifiers does consume Ampere heavily, like a hungry wolf...

And it is better to have way to many Amperes, than way to few...

im just curious as to what your final install will be in that car....could ya give me a clue....thanks

dedlyjedly · Post by **dedlyjedly** » Sun Dec 02, 2007 2:48 am

I would guess it's for this bad boy...
http://phoenixphorum.com/project-krank- ... t3790.html

Pedi · Post by **Pedi** » Sun Dec 02, 2007 4:03 am

dedlyjedly wrote:I would guess it's for this bad boy...
http://phoenixphorum.com/project-krank- ... t3790.html

Ohhhh yeah!!!

nico boom · Post by **nico boom** » Sun Dec 02, 2007 11:35 am

SOOOO.......
You've got FOUR girls... and ONE [bad] boy!

I know why you need that amps... you're afraid your girls will be louder than your car.

theburb · Post by **theburb** » Mon Dec 03, 2007 12:57 pm

i just saw the post about the old ambulance install....do you already have all that gear already....if you do why bother putting some much into that car....its a cool idea but its not like u are getting ready for the 1993 sema show

Pedi · Post by **Pedi** » Mon Dec 03, 2007 1:22 pm

theburb wrote:i just saw the post about the old ambulance install....do you already have all that gear already....if you do why bother putting some much into that car....its a cool idea but its not like u are getting ready for the 1993 sema show

Like I wrote in the thread, I want my install to be old school - to play Leila K and remember my good old youth... And ofcourse to enjoy the joy of good ol' PG - playing the ass off most of the todays teenagers, that laugh of the "old shit gear"...

And yes, I have the listed gear..

Post by **stipud** » Mon Dec 03, 2007 1:26 pm

theburb wrote:i just saw the post about the old ambulance install....do you already have all that gear already....if you do why bother putting some much into that car....its a cool idea but its not like u are getting ready for the 1993 sema show

Why are you building MS fan shrouds if you think installing old gear is pointless?

Just because something is newer doesn't mean it is necessarily better... If you read through his thread, you would see that the point is to show people like you that 1993 could rock just as hard as the current show cars

Modern show cars are a dime a dozen, thanks to the tuner scene. I think historical installs like Pedi is planning, or some of Nico's original setups are way more exciting to me. I think an old Opel Kadett or Volvo Ambulance with an SPL setup built in your back yard better embodies the car audio spirit than the mass produced cookie cutter setups you see nowadays. Wouldn't you agree?