Canada_Guy
I was doing my annual maintenance on my 14kw model 5612 LP generator. As part of my tests, I checked the battery voltage and it was at 12.94 volts. Seemed low as it normally sits at 13.4 volts. I checked after I had just shut down the generator after a 20 minute run to get it all nice an warm to drain the oil.

A few hours later after the oil change I rechecked the battery voltage and it was back to 13.4 volts.

I was curious what it was during cranking, so I clipped the volt meter on the battery and flipped the switch to Run. Battery voltage dipped to about 11.2 volts during the final part of the crank before she fired up. Seemed OK.

Here's the funny thing. I watched the battery voltage as it was running. It was at 12.6 volts and slowly dropped over the next 15 minutes to 12.5 volts.

I now wonder if the battery charger does not have enough current to fully power the generator ignition system. Does the generator engine itself have and charge circuit (I believe the answer to this is no, as previous posts mention that the battery charger must be powered by a generator backed circuit or else the battery will die during long power outages).

So now I wonder if the 1.2-amp (I measured it) battery charger/maintainer is sufficient. If I install an external one (as others have mentioned), I wonder if a 2-amp model is adequate, or maybe it really requires more like 5-amps?
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ohmslaw
The generator ignition is self powered. All the current draw comes from the start circuit, fuel solenoid and the controller board. I suspect a failing battery.
Tim
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Skip Douglas SkipD
The battery maintainer (charger) that I use is rated at 1.5 amps and has always been more than enough to keep my generator's battery in fine shape.
Skip Douglas
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Canada_Guy
SkipD;11257 wrote:
The battery maintainer (charger) that I use is rated at 1.5 amps and has always been more than enough to keep my generator's battery in fine shape.


It would be interesting to see what voltage it maintains the battery at while the generator is running.
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Canada_Guy
ohmslaw;11256 wrote:
The generator ignition is self powered. All the current draw comes from the start circuit, fuel solenoid and the controller board. I suspect a failing battery.
Tim


I thought about that, but the battery is only 2-years old. I also checked to see if the battery was sinking current into it while the generator was running so I put an ammeter in series with the battery and there was only aboy 10 ma (1/100 of an amp) flowing to the battery.
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rico567
Canada_Guy;11260 wrote:
I thought about that, but the battery is only 2-years old. I also checked to see if the battery was sinking current into it while the generator was running so I put an ammeter in series with the battery and there was only aboy 10 ma (1/100 of an amp) flowing to the battery.


I think all these sorts of air-cooled engines use what is called a permanent magnet alternator to supply current (mine generates 28VAC). I had to troubleshoot the one on my twin-cylinder lawn mower engine last year (turned out to be the rectifier / regulator). These devices incorporate a magnet built in to the flywheel, and the pickup / coil mounted to the side. Since my mower, once running, will operate perfectly well without the battery even being in it, I must assume that no battery current is required for motor operation. While the operation of the Generac OHVI engine may be somewhat different in detail from my engine (A Kohler Magnum), I suspect that as described it's about the same.

I would be looking to the battery or its connections....possibly a weak cell?
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