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bountyhunter wrote: Here's a ref explaining a DC generator:

farside.ph.utexas.edu/teaching/302l/lectures/node91.html

The Direct Current Generator
Most common electrical appliances (e.g., electric light-bulbs, and electric heating elements) work fine on AC electrical power. However, there are some situations in which DC power is preferable. For instance, small electric motors (e.g., those which power food mixers and vacuum cleaners) work very well on AC electricity, but very large electric motors (e.g., those which power subway trains) generally work much better on DC electricity. Let us investigate how DC electricity can be generated.

A simple DC generator consists of the same basic elements as a simple AC generator: i.e., a multi-turn coil rotating uniformly in a magnetic field. The main difference between a DC generator and an AC generator lies in the manner in which the rotating coil is connected to the external circuit containing the load. In an AC generator, both ends of the coil are connected to separate slip-rings which co-rotate with the coil, and are connected to the external circuit via wire brushes. In this manner, the emf ${\cal E}_{\rm ext}$ seen by the external circuit is always the same as the emf ${\cal E}$ generated around the rotating coil. In a DC generator, the two ends of the coil are attached to different halves of a single split-ring which co-rotates with the coil. The split-ring is connected to the external circuit by means of metal brushes--see Fig. 41. This combination of a rotating split-ring and stationary metal brushes is called a commutator. The purpose of the commutator is to ensure that the emf ${\cal E}_{\rm ext}$ seen by the external circuit is equal to the emf ${\cal E}$ generated around the rotating coil for half the rotation period, but is equal to minus this emf for the other half (since the connection between the external circuit and the rotating coil is reversed by the commutator every half-period of rotation). The positions of the metal brushes can be adjusted such that the connection between the rotating coil and the external circuit reverses whenever the emf ${\cal E}$ generated around the coil goes through zero. In this special case, the emf seen in the external circuit is simply:

I'm pretty sure that's what I said, but right now I'm not even making sense to myself.

Bottom line is that there is no single definition for any of those terms. In order to describe the charging system, you have to describe the charging system with more than one word. Even Kawasaki can't agree with itself on the terms.

loudhvx wrote: Bottom line is that there is no single definition for any of those terms. In order to describe the charging system, you have to describe the charging system with more than one word. Even Kawasaki can't agree with itself on the terms.

Yeah but I'm always right cause I'm so old.

loudhvx wrote: Bottom line is that there is no single definition for any of those terms.

That's what I think too. I have not seen them used consistently. The term "generator" is used to describe the large AC generators at big power plants which are strictly AC. Not sure if any actual consistent rules were ever established.

loudhvx wrote: Bottom line is that there is no single definition for any of those terms. In order to describe the charging system, you have to describe the charging system with more than one word. Even Kawasaki can't agree with itself on the terms.

True; even on the same parts diagram! Notice in the Kawasaki.com diagram below the cover for the generator is called a "Cover, Dynamo", but the gasket for that cover is called a "Gasket, Generator Cover." Ed

Some of those manuals are made in England, The queens english not American english.
The terms may not be what your used to.
Pass me a spanner to beat out those gudgeon pins!

Rectifier is the same as a diode trio, and converts AC to DC, Alternator.
Generator output is DC and does not require rectification only regulation.

The Japanese version may be lost in translation.

gearheadmm wrote: Some of those manuals are made in England, The queens english not American english.
The terms may not be what your used to.
Pass me a spanner to beat out those gudgeon pins!.

The spanners are in the boot where I keep the tool box.

gearheadmm wrote: Some of those manuals are made in England, The queens english not American english.
The terms may not be what your used to.
Pass me a spanner to beat out those gudgeon pins!

Rectifier is the same as a diode trio, and converts AC to DC, Alternator.
Generator output is DC and does not require rectification only regulation.

The Japanese version may be lost in translation.

I'm not sure it is possible to generate DC, I believe all generators/alternators generate AC, but that is then converted to DC in some situations.

Think about it, in every case you have a copper wire rotating through a magnetic field, so the voltage starts at zero, increases as the wire approaches the field, reaches peak in the middle, then decreases as it exits the field. And that's the definition of AC. In some generators a commentator is used to convert the AC to DC.

steell wrote: I'm not sure it is possible to generate DC, I believe all generators/alternators generate AC, but that is then converted to DC in some situations.

Think about it, in every case you have a copper wire rotating through a magnetic field, so the voltage starts at zero, increases as the wire approaches the field, reaches peak in the middle, then decreases as it exits the field. And that's the definition of AC. In some generators a commentator is used to convert the AC to DC.

I believe this is also the reason why electric motors are not more efficient. There is no continuously-rotating electric motor that runs on actual DC power. It has to be converted to AC or get switched on and off some way, which adds an AC component. The rotation must be divided into discrete pulses, instead of a single, continuous torque pulse.

steell wrote: I'm not sure it is possible to generate DC, I believe all generators/alternators generate AC, but that is then converted to DC in some situations.

Think about it, in every case you have a copper wire rotating through a magnetic field, so the voltage starts at zero, increases as the wire approaches the field, reaches peak in the middle, then decreases as it exits the field. And that's the definition of AC. In some generators a commentator is used to convert the AC to DC.

True but DC generators operate on the positive side only,
And AC generators operate on the positive and negative side of a sign wave.
That's the difference.

It is AC that is only positive with respect to the "reference" point usually called ground. It is typically called rectified AC or pulsating DC. It's not a steady DC voltage, it's a pulsating voltage.

gearheadmm wrote:

steell wrote: I'm not sure it is possible to generate DC, I believe all generators/alternators generate AC, but that is then converted to DC in some situations.

Think about it, in every case you have a copper wire rotating through a magnetic field, so the voltage starts at zero, increases as the wire approaches the field, reaches peak in the middle, then decreases as it exits the field. And that's the definition of AC. In some generators a commentator is used to convert the AC to DC.

True but DC generators operate on the positive side only,
And AC generators operate on the positive and negative side of a sign wave.
That's the difference.

No, take the back off any automotive generator (Old pre alternator) and you'll see two brushes, one connects to ground while the other connects to positive. And if you take a look at the generator armature using a ohm meter you will discover that every contact on the commutator is connected to another contact 180 degrees away. Hmm, I need to think about this some more, you may be right.

Edit:
Ok, I'v cooked and consumed my steak (had a T-Bone instead of my usual rib eye) and am still enjoying my drink, and I've thought it over, and I've figured out I don't even understand your statement.

Got to have a positive and negative to make a complete circuit. On a generator the positive side of the wave is connected to the positive terminal, and due to the mechanical location of the contacts on the commutator, the negative side of the wave is connected to the negative terminal. A mechanical rectifier.

I am going to become increasingly incoherent as the night goes on, and I'll be enjoying every bit of it