Need a SD dual alternator setup

907DAVE · Dec 31, 2011

Big Bore said:
This is true as long as the alternator will still put out the same amount of amps at 16v as it would at 14v. It may very well do that as 2v is not a lot, but the alternator is only capable of so many max watts and pushing it to the outside of it's performance envelope could lead to high heat and early failure. If in fact the amp rating at 14v is also the max watts output, then no, it wont put out more max amps. I'd be curious to know the truth of this, since the 6v deep cycle batts can be charged safely with 16v, the Trace inverter that powers my home will go up to 16.5v when charging.

Ohms's law...

Increase the voltage and amperage goes down.

I have seen regulators fail and alternators run over 18volts.....and the customer had been driving it like that for weeks without issues...lol.

Big Bore · Dec 31, 2011

907DAVE said:
Ohms's law...

Increase the voltage and amperage goes down.

I have seen regulators fail and alternators run over 18volts.....and the customer had been driving it like that for weeks without issues...lol.

Kinda what I was getting at, power (watts) = volts x amps. Maximum power output of the alternator won't go up if voltage is increased. So if the alt is 180A@12v, max wattage is 2520. Bumping up voltage to 16v will make max amps 157.5A.

Unless there is some circuitry in the alternator that I'm missing.

I'm betting that 18v wasn't good for his batteries. I'm pretty sure a constant 18v will be boiling the batteries (16v is an equalize charge (boiling) for 12v deep cycle batteries, and only for a couple hours to desulfate the plates).

907DAVE · Dec 31, 2011

What you are missing is that the devises that are drawing the amperage will use less because of the increase of potential.

I am by no means saying that cranking voltage that high will not have any consequences...just talking theory.

Big Bore · Dec 31, 2011

907DAVE said:
What you are missing is that the devises that are drawing the amperage will use less because of the increase of potential.

I am by no means saying that cranking voltage that high will not have any consequences...just talking theory.

Yes they will only draw the required wattage. Which goes back to my original question, what is the advantage?

907DAVE · Dec 31, 2011

That advantage being the amp draw would be reduced and the circuits would have less "strain" put on them....but as far as being practical - not likely.

Southmike · Dec 31, 2011

Hayes has a layout on it. There is one wire missing on the harness not sure how far you have to go to get it, as far as slplicing or adding one. The bracket is expensive from ford, i i just picked one up second hand but it is still at my sistersand then there is the belt.
Not tooo bad all in all, but no walk in the park either

Gearhead · Jan 2, 2012

Big Bore said:
4500W? are you using your truck to temporarily power your house? LOL

Sounds cool whatever it is. Care to share?

I would surge around 3500W on the jobsite if the compressor was running at the same time as a worm drive, but it was intermittent.

Big azz sine wave inverter with outlets in the bed..... want to roll up to a spot and run tools or my mig if i need to.