Alternator Output

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fraz627

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Question.. What is the normal outputs of the standard vehicle alternator, while Idling and while driving.
E-150 5.4 V8
 
On my V6 4Runner I get from ~13-14v. Yours should be similar. When i first start up its closer to 13.9v when driving its usually just over 13v.
 
Some of the newer cars are designed so the Alt will shut off when not needed. It saves on Gas. I know my Chevy 6.0l will do that.
 
In the old days the norm was 13.8 to 14.8 but like Freelander says the alternator on more modern vehicles is computer controlled. Anything from 12.0 to 15.2 could be normal while idling or driving.
 
My E350 ExAmbo now RV is diesel 12v w/2 big batteries & a 250 amp alt. & is the last year before computers so it does 13.8-14.8 volts.
 
What is the normal outputs
Others have addressed voltage. If you're looking for the output current rating (130A or whatever) you may want to mention the model year in case other owners can chime in. Or a ford-specific VIN lookup might tell you which OEM alternator the van was shipped with. When I searched "E-150 5.4 V8+alternator" I saw 95A, 130A, and 150A variants.

You probably already know this, but just in case: alternators don't put out their rated current at idle.
 
The ambo has a larger one for all the lights & equipment it can run. Do you know your alternator makes 3 phase AC?
 
I was going to mention it probably has a big Alt on it, and it may even have an extra one mounted somewhere.
 
Others have addressed voltage. If you're looking for the output current rating (130A or whatever) you may want to mention the model year in case other owners can chime in. Or a ford-specific VIN lookup might tell you which OEM alternator the van was shipped with. When I searched "E-150 5.4 V8+alternator" I saw 95A, 130A, and 150A variants.

You probably already know this, but just in case: alternators don't put out their rated current at idle.
Yes I was looking for the amps, trying to see if the alternator would could charge the house batteries, while driving say 4 hours a day, under normal driving conditions. my van is a 2001 e-150, and previously had a wheelchair lift, as wheel as other handicap accessories, such as push button brakes. Batteries are 2 6v FLA golf cart batteries, 215 amp.
 
I would think it would do fine. Now if you were charging 8 or 10 it would be different.
 
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I am only in Dodge Grand Caravan 3.3l.... And I have about the same amp hours you do. Hooked up to solar but.
Everytime I drive the car, it's charging car battery and deep cells. No problem.

Some winter days, no sun and camped on highway pull off during snow storm. I cannot set up solar or pull generator out so the car kept them charged. I have cable thru firewall and just connect negative side(positive stays connected and it's charging. Works too for topping off car battery from solar

So I would think with that V8... You are good
I did read charging that way is not the best idea because you might be overcharging the car battery... But it does work.
 
Yes I was looking for the amps, trying to see if the alternator would could charge the house batteries, while driving say 4 hours a day, under normal driving conditions.

My GC bank pulled ~40A from the alternator, decreasing steadily as the bank rose to alt voltage.

IMO 4hrs/day isn't long enough to complete Absorption for cycled lead batts even if the alt happened to put out the proper voltage. It tends to take 5-6hrs at manufacturer-recommended Vabs.

Adding mounted solar or DC-DC charging to the mix would provide required voltage. Solar would address duration.
 
Question.. What is the normal outputs of the standard vehicle alternator, while Idling and while driving.
E-150 5.4 V8
any alternator that is in use, will put out amps and volts. the more rpm the more amps, until the battery's start to reach full charge. then the alternator will lower its output. so it's always changing at some level. any alternator will charge even 10 batterys just not very fast. 10 battery's would take days to fully charge at 4 or 5 hours a day and may never fully charge if they are also used to power devices when not charging. we used to charge extra battery's for a boat and a travel trailer and they charged off a 35 amp truck generator (not an alternator). running the truck 3 hours a day for a 5 days.

to get any alternator to output more amps you would need to swap out the pulley to a smaller pulley. so at idle it would put out more power (amps), this output would increase with rpm.
 
I left the master switch on for over a week & it started fine but put out the most I've seen it do, 150 amps at idle. The old DC generators barely put out at idle.
 
Question.. What is the normal outputs of the standard vehicle alternator, while Idling and while driving.
E-150 5.4 V8
The regulator that controls the alternator regulates the voltage, (not the amperage). It is set between 13.8 and 14.6 volts.
The amount of amperage is determined by the size of the alternator windings and how much the batteries and other loads will accept. Vehicles will have an alternator that can output 60 amps or more, but a lead acid battery can take several hours to fully charge even though it may be down less than 50 amp hours. It takes time for the incoming electricity to reverse the chemical reaction that produced the electricity that came out of the battery.
 
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