Setting Generator Output

[Tom Wesenberg]

The other day I heard about someone thinking setting the output on the powerhouse generator was opposite the way it's done on the long generator. IT ISN'T, it's exactly the same. To increase the output the adjustable brush is moved in the direction of rotation. In other words just see how the armature is turning and move the brush the same direction to increase the output.

Several days ago I said as the adjustable brush is moved AWAY from the ground brush the field windings will get more voltage, thus increasing the generator output. While this is true for the long generator, the powerhouse is arranged differently. You can see the adjustable brush is set between 2 ground brushes on the 5 brush powerhouse, and on the 3 brush powerhouse the output increases as the adjustable brush is moved CLOSER to the ground brush. To avoid confusion I should have said "the output is increased as the adjustble brush is moved away from the ground brush POLARITY".

You can see in these two pictures that the powerhouse is a 6 pole generator. That is it has 6 field windings, each pole opposite the polarity of the pole next to it. So if the ground brush is next to a pole of north polarity, then as the adjustable brush is moved closer to the center of a south pole, the output increases.

When is doubt just look in the owner's manual for generator output adjustment. It's on page 33 in my manual.

In this picture of the 5 brush powerhouse (green background), the adjustable brush is set for MINIMUM output and yet when I tested this generator on my test stand yesterday it showed 11.5 volts at 12 amps going into my 6 volt battery.
The reason for this is because the battery on my test stand is shot and can no longer hold a good charge, nor begin to start an engine. When a battery gets worn out the resistence increases and is less able to control the generator output. That's just one more good reason for using an electronic voltage regulator. If I installed this junk battery in a car, then hand cranked the engine to start it, if I turned on the lights the high output of an unregulated generator would blow all the bulbs instantly.

[BudP]

Tom-Can you give out a little more information on your manual? Name? Availability? Thanks a lot.

[sethkestenbaum]

Tom,

What other things (aside from a worn battery) that might result in output being too high if the Powerhouse is set to the minimum output?

Seth

[Bill Goddard]

Tom, I would appreciate a disertation on the effects of bad 80 yr old ground connections on generator output, extra bright headlights, battery charging and I don't know what else. I have been hearing a lot of questions in my club circles that are I think the result of basic mis understanding of the effects of old corroded grounds and I'm not really good enough to explain them. Hope yu can enlighten me. Thanks Bill G

[glenn in camino]

Tom puts out a generator manual?????? I want one.

[Tom Wesenberg]

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The grounds, including the generator mounting bolt, are part of the charging circuit. Anything that increases resistence in the circuit will mess with the generator output and allow the voltage to increase to dangerous levels. This could include a weak battery, loose or corroded grounds and any connections in the charging circuit. The terminal box and amp guage are in the charging circuit, as well as a fuse if you installed one. BTW, if the generator runs very long with too high an output it will burn up internally. I've seen a fair number of generators with fried field windings and bad armatures.

The nice thing about an electronic voltage regulator is the generator output is controlled right at the generator, so even if you failed to keep clean tight connections, the output remains at a safe level for the lights and coil.

The generator makes electricity by spinning coils of wire through a magnetic field. You can increase the generator output by increasing the armature speed and/or increasing the strength of the magnetic field. The EVR turns the power on an off at a very rapid rate to control the voltage going to the field windings, which controls the magnetic strength, which controls the voltage output of the generator.

Sorry, but until I find my crayons there will be no book!

[BudP]

Ooops! When you referred to "my manual," you meant "my owner's manual." My mistake. Regardless, your contributions to this forum are educational and well-worth saving for reference.

[Bill Goddard]

Thanks Tom, I guess it boils down to going over all electical contacts AND paths which have after 80 yrs gone from poor to bad. I suggest this to owners with electical problems and I get a deer in the headlights look. I guess its not as much fun to overhaul the wiring as it is to do a transmission, but the wiring is far more likely to put you at the side of the road. I have no simpathy for the "if it ain't broke, don't fix it" approach.

[Tom Wesenberg]

Bill, there is an easy way to check for poor connections. You just have to check for voltage drop by connecting the volt meter to either side of the point in question. To check for voltage drop you need current flow, so you'll need the engine running for generator output. If you suspect a poor connection on the ground side of the charging circuit, just put the + meter lead on a good ground at the generator, and put the - meter lead on the positive battery post. If this sounds strange to put the negative lead on the positive post just remmeber that the generator is working, so the generator case should be more positive at this time than the positive battery post. Anyway you are hoping for a very small reading, like maybe .2 volts or less. The higher the reading (voltage drop) that means the more reisistence is in the ground side of the charging circuit. If you find a high reading, then remove the meter lead from the battery post and move it to the frame to see if you still have the high reading. If the high reading went away with the move to the frame, then look for a bad battery ground.

You can do the same voltage drop check for the wired side of the charging circuit by putting the - meter lead on the generator post and the + lead on the negative battery post. Again you want a low reading like a couple tenths of a volt or less.

It's the same thing to check for a poor connection in the lighting circuit. You need current flow to get a voltage drop, so turn the lights on and start checking between the suspect points, looking for a voltage drop.

[Tom Cavallaro]

Tom, I read that you developed some sort of regulator you put inside of the generator...did I understand correctly? If so how can I obtain information.
Thanks