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| | | | Joined: Apr 2019 Posts: 122 'Bolter | | 'Bolter Joined: Apr 2019 Posts: 122 | I'm new to generators.
How do I determine if my generator is working properly or if it needs to be polarized?
I installed new gauges and had the battery disconnected. If I start the truck, the ammeter is basically not moving. Shouldn't the ammeter be reading more than 0 if the generator is charging the battery?
I had to charge the battery this morning because it didn't have enough juice to start the truck.
Thanks,
JD
1951 Chevy 3100 1/2 ton (1957 235, 4 speed, 411 rear)
| | | | | Joined: Feb 2004 Posts: 29,760 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,760 | Check the terminal voltage at the battery posts with the engine at fast idle. It should be 13+ volts, minimum. Against a fully charged battery with the engine at a fast idle, the voltage should go to 14.5 or slightly more.
Yes, the generator need to be polarized. Even if it's already polarized, doing it again won't hurt anything. With the engine stopped, use a short jumper wire to connect the BAT and ARM terminals of the regulator together momentarily- - - - -half a second or so is plenty. You'll get a pretty good arc- - - -don't get a case of the vapors- - - -that's normal.
Now, with that little chore out of the way, go ahead and check the generator for voltage and current output. If you don't know how to do that, find somebody who does. Relying on the dash ammeter to give an accurate measurement of charge/discharge current is not sufficient. That meter is a WAG at best.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Apr 2019 Posts: 122 'Bolter | | 'Bolter Joined: Apr 2019 Posts: 122 | Thanks Jerry. How can I tell the ARM terminal? I don't remember if they are labeled (I'm at work). I can trace the battery terminal back to the ammeter/battery.
1951 Chevy 3100 1/2 ton (1957 235, 4 speed, 411 rear)
| | | | | Joined: Feb 2004 Posts: 29,760 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,760 | They're stamped on the terminal lugs of the regulator- - - -BAT- - - -ARM- - - -FLD. "Battery- - - -Armature- - - -Field". The armature wire is usually in the middle. The Field terminal will also have a very small-gauge wire. Battery and Armature wires are noticeably larger gauge. It's also a very good idea to run a dedicated ground wire from the regulator base to the generator housing, if one isn't there already.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Apr 2019 Posts: 122 'Bolter | | 'Bolter Joined: Apr 2019 Posts: 122 | Ok, I polarized the regulator. I drove the truck around for about 10 minutes with no accessories on.
I'm getting 14.5V at the battery with the motor at fast idle now.
Thanks Jerry.
1951 Chevy 3100 1/2 ton (1957 235, 4 speed, 411 rear)
| | | | | Joined: Feb 2004 Posts: 29,760 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,760 | It would be a good idea to invest in a "battery maintainer" if the truck doesn't get driven regularly. It's similar to a trickle charger and it prevents the battery from self-discharging over several days or weeks of inactivity. To charge a low battery properly with a generator (or even an alternator) takes several miles of driving. 30 minutes to an hour, minimum.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | It would be a good idea to invest in a "battery maintainer" if the truck doesn't get driven regularly. . . .
Jerry | | |
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