What is a High Output Alternator composed of?

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what exactly gives a high output altenator more output?

from what i understand increasing the flux density or increasing the revolutions will provide more current.

do they have shorter thicker wire, or more densely packed thinner wire? or is the part that spins modified (forgot what its called).

how about the electronic portion eg; the regulators and such , how do these play a part in the chain?

i dont see any reason why we can't DIY alternators as well...

thanx
 
I could be wrong but I believe that the term armature is generally used for DC motors/generators. Generally, an armature has a commutator for the electrical contacts. The rotor of an alternator has slip rings.

A high current alternator uses larger wire. Since there is limited space, there will be fewer turns. With the OEM windings, the alternator can produce relatively high current at low RPMs and still maintain the target regulated voltage. With fewer turns in the high current alternator, the winding ratio is lower and you have to spin it faster to maintain the target voltage. At low RPMs, the voltage may drop, even at relatively low current draw.

HC alternators may have larger rectifiers and better cooling (larger internal heatsinks and/or better fans).

The regulator doesn't have much to do with the high current output. The regulator drives current into the rotor. When the voltage starts to drop, the regulator drives the rotor harder to produce more output so that the target voltage is maintained.
 
I got a high-output rebuild kit from J. C. Whitney for the common Ford alternator; it consisted of a new stator, and a new set of rectifiers. I've heard that the high output alternators don't put out as much current at low RPMs, though. I haven't installed this kit, so can't confirm or deny that. It wasn't very expensive; you should ask a local car parts dealer if they have something similar for your model.

If you don't have a voltmeter, a digital one will tell you a lot about what's happening with the charging system.
 
Automotive ALTERNATORS (as opposed to DYNAMOS) uses (two) slip rings as outputs, and they also have built-in rectifiers and regulators. Thus, you have your DC output to charge your battery. A high output alternator can have larger wire for the windings, larger rectifiers or even larger cases to accomodate the same number of windings (as opposed to normal alternators) but of larger diameter wire. Each manufacturer may have their own criteria and/or financial considerations. Most modern alternators have current ratings of around 100 Amps or so, and this should be sufficient, in my personal experience, for ordinary use, even for a relatively high powered system (500W RMS total or so). SPL competition is in a different world......
 
i have a few old alternators laying around and took one apart lastnight...the one i took apart is a 60ah nissan, but have 2 more toyota 100ah alts laying around.

the outer windings look like they can accomodate thicker wire if i drill the holes out just slightly (will post pic)...or if i can find thicker wires from another manfacturer...and hopefully fit inside the same casing it may be possible....for this certain step....

but for the part that actually spins...i cant get it out :xeye: , may have to get it hydraulicly pressed out.

the rectifier has no markings on it, so this is going to take a bit of research to find out what exactly it is...

i think this is possible, theres people here that rewind alts, but finding them is like looking for a unicorn...and they may not be doing it properly.

i just got a quote from HO (america armature ) and it was for $649 for a 170 amp misubishi alt , for a nissan sentra...aint no way im paying that for a $50 increase in part cost and $50 for actual donor...the rest is pure profit...

i'll take pics once my batteries charge up....
 
Perry Babin said:
I could be wrong but I believe that the term armature is generally used for DC motors/generators. Generally, an armature has a commutator for the electrical contacts. The rotor of an alternator has slip rings.

A high current alternator uses larger wire. Since there is limited space, there will be fewer turns. With the OEM windings, the alternator can produce relatively high current at low RPMs and still maintain the target regulated voltage. With fewer turns in the high current alternator, the winding ratio is lower and you have to spin it faster to maintain the target voltage. At low RPMs, the voltage may drop, even at relatively low current draw.

HC alternators may have larger rectifiers and better cooling (larger internal heatsinks and/or better fans).

The regulator doesn't have much to do with the high current output. The regulator drives current into the rotor. When the voltage starts to drop, the regulator drives the rotor harder to produce more output so that the target voltage is maintained.

The term armature has nothing to do with it being Ac or Dc, your normal power tools which are Ac have an armature and these can run on Dc as well.... Having slip rings or a commutator are both found on armatures, a rotor is used in a squirrel cage induction motor which has no actual windings as such they use solid bars instead of wire windings and a rotor also has no form of electrical connection so they have no commutators or slip rings.
I hope that this clears up that side of things some.....
 
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