How to flash an AC generator

Hi Guys, I've just had cause to put the newly rebuilt generator to work this week. I was sitting on my computer as I do one evening when everything went
black in the world around me. We had lost our mains supply to the complete area and everyone was in darkness.
Well this was the moment I must have been waiting for!! I carefully ran down the stairs with a cry of don't worry we have a Generator and proceeded to the garage. A couple of minutes later we had lights running of extension leads and at least we could see. The power was out for almost an hour but I was quite smug in the thought that my back up plan had come into use so soon after rebuilding the generator. I was like a dog with two tails!! :o) Unfortunately the half cooked roast dinner in the oven had to wait until the main power came back on. :o(
The next stage I think will be to install a socket via an isolator switch which will enable me to isolate the lights circuits in the house from the mains and plug the generator directly in to avoid the need to have lead lamps and extension leads running everywhere.
Thanks again for everyone for their input in getting the generator up and running.
--
Kindest Regards

Tom

"Tom Horne" < snipped-for-privacy@veriqrmzon.net> wrote in message
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wrote:

'Tis sweet, isn't it? Hope your neighbors saw the light which makes it even better.
I have my cabin set up with a manual transfer switch but still use a roll-out generator, an artifact from before I retired and moved here to my mountain cabin permanently. I didn't want a generator outside permanently where it could get stolen.
Last August there was a scheduled outage that was supposed to be for 4 hours for a substation upgrade but ended up stretching to over 15. We had warning so I rolled my generator out, hooked up the cables (power and remote starter) and was ready. When the lights went out, I threw the switch, hit the starter and viola! My lights and most importantly, my AC and wellpump were back in action. Later that evening I DID cook supper on my electric stove.
Next morning I went down to the general store for the morning chat'n'chew. I pulled up on my electric scooter which was silent. I heard my loud-mouth neighbor running his mouth to the proprietor, bitching about how that SOB neighbor of his was the only place up there that had lights last night. I slipped through the screen door and let it slam loudly behind me. Loud-mouth jumped and when he turned around he looked like the cat caught in the canary cage. Had I bought the generator with a MasterCard, it could have been
1 7kw generator            $1,800 2 7 gallon tanks of fuel    $50
Pissing off your neighbor    Priceless!!!!!
John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN Risk: $20 hooker, year old condom.
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Hi John, yeah it was sweet in a smug sort of way. There was only us an a mate up the road who had lights. He's a builder and he also had a generator which he uses when he's on site. Everywhere else was flickering candles. I've did have some comments from friends & neighbours but all in a friendly banter sort of way.
Cheers
Tom
wrote:

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Basically you need to magnetize the field winding with say a 12vdc source. The owners manual typically will describe the procedure. The last gen that I flashed was a industrial 50hz 3kw motorized generator. I disconnected the field and fed 12vdc into the field windings. As long as the field core is slightly magnetized it will be enough to get the stator to produce enough voltage to get the exciter going.
Cheers

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wrote:

Get a 12 volt battery, use the one in your car or use a battery charger if you have one with sufficient current capability. Open up the connection box on the generator and find the leads coming from the stator. These connect to the outlets. Disconnect them from any other wiring and momentarily connect them to the 12 volts. Simply brushing the wire from the battery against the generator wire will be enough. Reconnect the stator wires and crank.
This pulse of current re-establishes the residual magnetism necessary to bring the generator up when started. This magnetism can go away over time.
If the above "static flash" doesn't work then do a "dynamic flash". Connect a "Jesus cord" (plug on one end, alligator clips on the other) to the outlet on the generator. Connect a 100 watt 120 volt bulb in series with the hot leg. Apply the 12 volts between the bulb and the neutral of the line. The instant the DC current flows, the generator will start generating 120 volts AC. The bulb is to prevent much AC current from being applied to the battery. The bulb should light instantly and remain lit as long as the battery is connected.
If this doesn't work and if your generator has slip rings and brushes then the next step is to see if the brushes are stuck in their holders and/or the slip rings are glazed over, preventing the rotor field from being energized. At this point you really do need the manual to assist with locating the brushes and accessing them.
John -- John De Armond See my website for my current email address http://www.neon-john.com http://www.johndearmond.com <-- best little blog on the net! Tellico Plains, Occupied TN Okay, okay, I'll take it back ... UNfuck you!
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the
fine
that?
Before you flash it try prodding the throttle and see if some increased RPMs will get it going.
I've done it with a 6 volt 5 Ah battery with success. I just connect one side of the battery to the AC output and while the engine is running momentarily connect the other side. Once the AC voltage starts to climb I disconnect the battery. You might want to put a fuse in line with the battery so you don't blow it up. Then run it for a while with a load (like someone else said).
I've not done it sucessfully with the generator not running. It sounds safer but had no effect on my particular genny.
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