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Old 08-15-2013, 06:50 PM   #1
jrelliott
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Default Generator Voltage

Have later style generator after Power House. Set the Current to 8 Amps at high idle, then checked the voltage with a analog voltmeter and it is just over 8 volts which in my opinion is too high. What do other people get at the output of the generator when at this current setting.

Power house is only putting out 2 Volts any ideas as to what to check. Connections all clean and tried holding brushes a little tighter and no change in voltage. Generator was polarized prior to making the measurements at the input to the cutout. Generator worked for a while and all the field coils have continuity and have about the same ohmage in each coil.
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Old 08-15-2013, 09:02 PM   #2
Kurt in NJ
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Default Re: Generator Voltage

If it is a diode cutout it will be about 1/2 volt higher on the generator side of the cutout, also check the batt side of the cutout, and at the battery ---if there is a 1/2 volt difference between the batt side of the cutout and the battery look for bad connections.

the state of charge of the battery will make a difference in the voltage --fully charged battery will have a higher charging voltage than a almost dead battery the age of the battery will make a difference also --older batteries don't like to charge as much so the charging voltage will be higher

in a 3 brush charging system the battery is in essence the voltage regulator
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Old 08-15-2013, 10:53 PM   #3
Tom Wesenberg
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Default Re: Generator Voltage

In the 5 brush and 3 brush powerhouse generators the ground current travels through the brush wire to the top of the brush spring post, then down to the metal of the mounting leg. I've seen a few where the POST to FRAME connection was bad. I use an Exacto knife to scrape it clean then solder the base of the post to the frame.

8 amps is too high unless you do a lot of short drives and starts. The best solution is an electronic voltage regulator.
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Old 08-16-2013, 05:20 AM   #4
B_man_Al
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Default Re: Generator Voltage

I'm confused ... Is the output voltage 8V or 2V, or is the generator 2V and the battery 8V
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Old 08-16-2013, 05:27 AM   #5
Tom Wesenberg
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Default Re: Generator Voltage

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Originally Posted by B_man_Al View Post
I'm confused ... Is the output voltage 8V or 2V, or is the generator 2V and the battery 8V
He mentioned 2 generators, and the long style had been adjusted to 8 amps charge, while a powerhouse he tried put out 2 volts.

The most common problem I've seen with the powerhouse is a bad armature and/or broken brush holder. It's pretty rare that a powerhouse has burned field windings because they have 4 ohms on the 5 brush and 3 ohms on the 3 brush, so the currect running through them is much less than the long generator with only about 1 1/2 ohm.
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Old 08-17-2013, 11:36 AM   #6
jrelliott
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Default Re: Generator Voltage

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Got another armature for the Power House that had tested on a growler and the commutator turned and under cut. The Power House generator worked for a couple of minutes at a bout 15 Amps our then quit. Hope this armature is not shot also. Thanks for the hints. Was out of town yesterday so could not answer until today.
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Old 08-18-2013, 07:58 PM   #7
Tom Wesenberg
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Default Re: Generator Voltage

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Originally Posted by jrelliott View Post
Got another armature for the Power House that had tested on a growler and the commutator turned and under cut. The Power House generator worked for a couple of minutes at a bout 15 Amps our then quit. Hope this armature is not shot also. Thanks for the hints. Was out of town yesterday so could not answer until today.
Remove the field wire and connect a 6 volt battery charger between the field wire and ground. Youm should show from 1 1/2 to 2 amps on the charger amp meter.
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