People keep saying a alternator is better than a generator. So why is a 50 amp alternator better than a 50 amp generator. I want to compare apples to apples so keep 50 amp in mind and not go on a high output tangent. I do agree an alternator is better for higher output in a vehicle that requires it. Also the voltage regulator is not part of the alternator. There is an electronic regulator combined with some units but not all. You can put an electronic voltage regulator on a generator.

1. The highest output legal headlamp is 55 watts x2 = 110 watts or 9.6 amps at 12 volts.
2. The AM radio draws about 3 amps in my truck at 6 volts. So put in a regulator drop that from 12 volts and you are using 1.5 amps.
3. The heater motor draws 6 amps at 6 volts so at 12 volts it would draw 3 amps.
4. The horn draws 12 amps at 6 volts or 6 amps at 12 volts.
5. Anybody know what the ignition system draws? The calculations above leave about 30 amps. With the small gage wire that is on there I bet it is closer to about 1 or 2 amps.

 

Christopher

Here's the Effie English version of why the OEM used alternators.

Alternators tend to charge better at slow engine speeds. They are far more compact, especially whe you get higher up in the amperage range. An alternator tends to be more reliable. In my opinion, an alternator is a little easier to diagnose and service. Not to mention cheaper.

I'm not sure what your master plan is now. If you're certain you are not adding accessories down the road, there is no big emergency to upgrade to an alternator.

And this is a dangerous question to ask with "certain people" on the board. I have a feeling you may soon learn where and how copper in mined.

 

Chris,

Alternators are also easier replaced and to find parts for. Try to find a place to fix or replace a generator in Yehaw Junction (no disrespect intended to you folks there...been through there a few times and it's really nice!).

Vern

 

I think people don't like generators because they are not understood. I have run a generator in my truck for 16 years and had almost no trouble with it. Until I had it rebuilt. Then I bought every part inside it new cost me about $75 after that it will put out 60 plus amps. But in its stock 30 amp form I never had trouble with any thing. Both generators and alternators do the same thing one is heavy with heavy duty parts and the other is light with light parts in it. If you learn how a generator works and understand the system it will save you a lot of problems. But if you just want it to put a one wire on that will work also.

 

The Big Diffrence from A 50 Amp Alt and a 50 Amp gen is manly torque.. The reason is the wieght or the roatating parts and resisints of the current. A gen while in a 50 amp to 50 amp case wil but out the same amps. The Gen take more Hp from the engine to do the same job. Also the Gen is slower to respone to load demands as fast as a gen would.. In a lots of cases a Alt save U HP by uses Less torque and responding faster to load demands. Plus If You or someone else want to add a high power CD system the Amps come in higher Amp rating than a gen. Of If U add a high power Ing system the same thing applys.. And then there the cost or replacment and repair.. Alt are much cheaper. And easyer to get at a Junk yard in a lot of cases.. The choice is yours, If U are going for Stock Show point than keep the gen.. If U are using it as a every day driver than A alt will serve U much better..

 

"I think people don't like generators because they are not understood."

57ford

I think it's more a case of progress. Alt is just more efficient. Much more power from far less bulk and weight. Alternator is at least as reliable as a GEN. That's being kind IMO.

95% of the trucks in my military motorpool use a 60AMP Generator. They are huge, heavy, expensive ($408 ea last I looked). We're doing good when we get more than a couple years service or 10,000 miles. They won't take anymore abuse than an ALT in my opinion.

All that said, a GEN can work fine on a stock Effie.

 

He's just jealous, Chris, 'cuz he don't know how they mine copper. Now, here's how they do it ...

In fairness to 'fenders, he hit the reasons the OEMs use alternators now. Alternators can produce a lot more current at low engine (and alternator) speeds. A 50A generator will only produce 50A at a much higher RPM than a 50A alternator. The red, blue, and green curves below are for typical automotive alternators using a typical 3:1 pulley ratio. You can see that the alternator puts out almost full current at low engine RPM. I don't have a generator curve, but I've shown an estiamte on the chart. You can put a smaller pulley on the generator and spin it faster, but then it will wear out faster. More importantly, alternators are simpler and cheaper to build for a variety of reasons. We all know how much car manufacturers love cheaper stuff when they are building a vehicle. It keeps our vehicle costs down too.

 

Yeah, but so are plastic cars and brushed aluminum. Some people think that's normal stuff for vehicles cause they've never owned anything else.


I've run a gen on my 48 for over 3 years daily driving. During that time I did lose the front bearing, but the gen had never been rebuilt - I just pulled it off the pile. Also I had the belt too tight - my stupidity - which is the reason it failed.

It's all a matter of personal preference. Generators do the job they were intended for. When guys have problems with them it's usually cause they're pushing them beyond their capabilities. That holds true with alternators as well. Simple physics.

 

Good points, Tim. I'm going straight stock and the generator will work fine for me too.

 

Aside from the other info above there is a key consideration; generators with mechanical regulators produce a very disturbing spike in the system when they turn off and on (when they regulate). It can fry electronics! It can be as much as 300 volts, very short furation but I know of many people running 6v gens that have fried their Pertronics breakerless ignition modules in less than 20 miles. I would not connect a modern CD/radio or electronic ignition to a gen-equipped car (6v or 12v) unless you put a really good filter on the output, to clip these spikes. Modern cars with EFI cannot use generators.

-- Ross

 

"Yeah, but so are plastic cars and brushed aluminum. Some people think that's normal stuff for vehicles cause they've never owned anything else."

Tim

Are there any modern vehicles, foreign or domestic equipped with a generator? Honest question. Last one I recall messing with was on a VW. Early 70s I think. I am reminded here daily of the great wisdom of the OEMs engineers. Surely at least one of them still uses generators since they are so wonderful.

 

I'm reminded of your earlier post, specifically "... This is a dangerous question to ask with 'certain people' on the board. ... "

I think you are getting perilously close to a discussion of the definition of, and technical differences between, a generator and alternator. We surely don't want to go there!

 

Yeah I did my time in the Navy I seem to remember putting on very few miles but 100's of hours. Where else can you put the vehicle in gear and take a nap.

 

"I'm reminded of your earlier post, specifically "... This is a dangerous question to ask with 'certain people' on the board. ... "

Im sorry George, did you think I was referring to you

We're not in disagreement on a darn thing and you know it. And at no time did I suggest Christopher needs to switch to an alternator. At least it isn't required to fulfill the charging system needs for his this weeks plan. Keep us posted Christopher.

 

Dewayne
None that I'm aware of. But isn't that because of all the hi-tech voltage-fussy stuff we have in our vehicles these days? The stuff we deem the basics of life? Shoot, my 48 doesn't even have a radio let alone an amp-eating stereo system, but I like it that way.

If you're keeping your truck basically stock, the generator will do fine. I'm only pro-gennie to offset the opposite extremists who's first words are, "Oh no, a generator - better rip that sucker out and put in an alternator"

I'm aware of their limitations and have never suggested putting one in a new rig. I even own/drive some of those plastic and brushed aluminum trucks with alts.