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Discussion Starter #1
Of all the times to find out your generator won't work;
My mother in law called here at 6:30 AM yesterday to tell us that the tornado we heard about that hit ~35 miles away on the news had hit her house, and "thought" that she remembered that I had a generator that I'd used when we were last out of power.
So I load it in my truck and head up. Hook it up (had not been started in ~a year or so) and..... motor starts like always (thanks to Sta Bil I believe) but... open the fridge (we plugged it in direct) and... no light. so I find 2 circular saws and... nope no power.
I hit all 3 reset switches then remember that I'd never used "those" plugs so they may well have been dead since I have had it. so I go buy a twist lock plug and make a "custom" adapter extension cord... nothing.
this is a 15-ish year old Generac that my Dad had bought new and has always worked... until now. the last time I was out of power it worked flawlessly. Now..... nothing.
We wound up borrowing a generator elsewhere close by and got her going (Com Ed has since restored teh power to their house)

but..... why would a generator work fine last time and not at all this time? It has been in my dry garage ever since the last time it was used. I didnt feel like taking the panel apart "right then" under those conditions especially since we had another generator readily available....... but meanwhile... what to do now, so it works next time?
Do they lose "polarization" like an old starter generator?
 

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you need to excite the field. take a corded drill, plug it in the genny, pull the trigger and then turn the chuck backwards by hand. this will induce some voltage to the genny and hopefully it will work properly. this is why you are suppsoed to exercise gen set with a load. just running them does nothing for the gen head.

edit: meant to add i prefer to plug up a hair dryer or a couple of worklights when running my genny. it lets me put a known load on it of at least 1000W. of course, smaller gensets don't need to be overloaded. a 100W bulb is really all it takes but i like to get a good load on them.
 

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Discussion Starter #3
thanks. I will again be there tomorrow and I'll try that. (gotta stop and buy a gas powered pole pruner on the way up there)

Do this with the genset engine running? and no, I have NOT run the genset since my last power outage. nor has it been run "just for the sake of running it" the only time it has had no load on it was from the time I fired the engine til I could reach the plugs and plug them in. Couple minutes maybe.
 

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" Field Flashing of Portable Generators

This tip comes from the Briggs & Stratton Customer Education Department. As an alternative to flashing a rotor winding with a battery applied to the brushes, an electric drill may be used. Follow these steps to flash the generator:

* Plug the electric drill into the generator receptacle.

* If the drill is reversible, move the direction switch to the forward position.

* Start the generator

* While depressing the trigger on the drill, spin the drill chuck in reverse direction. This will excite the field and the generator will now produce electricity. If spinning the chuck one direction does not work, try spinning the chuck in the other direction as you may have the reverse switch positioned backwards.

Use caution not to get your hand or other materials caught in the chuck. As soon as the field is excited, the generator will produce power and the drill will turn on.

The reason this works is because the electric motor in the drill will act as a small generator when spun backwards. The magnets in the drill's motor induce a voltage into the motor windings, which is fed back through the trigger, cord and into the generators receptacle. From there it goes into the power winding of the stator. The voltage going through the power winding creates a magnetic field, which is intensified due to the iron core of the stator laminations. The rotor intersects this magnetic field as it is spun past the power winding, thus inducing a voltage in the rotor winding. Once current flow is present in the rotor winding the rotor has been flashed.

If flashing the field does not make the generator work, you may have additional problems, besides a lack of magnetism in the rotor. Further testing will be needed. Hopefully, this will give a simple way to field flash your generator if needed"
 

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yes, do it with the genny running and the breakers ON. don't grip the chuck too hard, as once it excites it will come up to power quickly and the chuck will instantly try to spin in the proper direction. you want to turn it backwards, but have the drill set for forward.

just sitting there and not being used will cause it just like running it with no load, the field just breaks down over time.

BTW, the same thing happens to tons of welders. excite the field and a bad welder is fixed!
 

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I'm glad I read this post. I think I will make a copy and attach it to my generator. Just in case.
 

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:ditto:Good "just in case" info here. :thanku:
 

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" Field Flashing of Portable Generators

This tip comes from the Briggs & Stratton Customer Education Department. As an alternative to flashing a rotor winding with a battery applied to the brushes, an electric drill may be used. Follow these steps to flash the generator:

* Plug the electric drill into the generator receptacle.

* If the drill is reversible, move the direction switch to the forward position.

* Start the generator

* While depressing the trigger on the drill, spin the drill chuck in reverse direction. This will excite the field and the generator will now produce electricity. If spinning the chuck one direction does not work, try spinning the chuck in the other direction as you may have the reverse switch positioned backwards.

Use caution not to get your hand or other materials caught in the chuck. As soon as the field is excited, the generator will produce power and the drill will turn on.

The reason this works is because the electric motor in the drill will act as a small generator when spun backwards. The magnets in the drill's motor induce a voltage into the motor windings, which is fed back through the trigger, cord and into the generators receptacle. From there it goes into the power winding of the stator. The voltage going through the power winding creates a magnetic field, which is intensified due to the iron core of the stator laminations. The rotor intersects this magnetic field as it is spun past the power winding, thus inducing a voltage in the rotor winding. Once current flow is present in the rotor winding the rotor has been flashed.

If flashing the field does not make the generator work, you may have additional problems, besides a lack of magnetism in the rotor. Further testing will be needed. Hopefully, this will give a simple way to field flash your generator if needed"
ThkU PaulChristenson, for the HUDGE / COST SAVING explanation / tip:

I got a large L/C Honda generator (from estate), that is suffering from the same "de-energized" problem, plus it needs a $400 carbutetor:
- O'h well / one problem at a time....

If the moderators are looking
- maybe a post like this one could be voted in a new category / TOP 10 OF THE MONTH TIP !!

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Beaumont { :>)) www.petperfectexpress.com
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1992 JD 318 original paint w/484 hr. on P218g Onan & #49 snow blower / 1998 JD GT262 w/brand new Kawasaki OHV & 48" rebuilt deck
http://www.mytractorforum.com/showthread.php?t=135838
 

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I Love All Color Tractors
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Great information and advice fellas. Thanks a bundle.
 

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Are you sure the breakers aren't tripped, perhaps from being transported? Sometimes breakers will trip from a physical shock, such as vibration or being dropped.

Good idea for flashing the generator! I, too,will make a copy and put it next to my generator.
 

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Discussion Starter #12
Are you sure the breakers aren't tripped, perhaps from being transported? Sometimes breakers will trip from a physical shock, such as vibration or being dropped.

Good idea for flashing the generator! I, too,will make a copy and put it next to my generator.
resetting the breakers was the 1st thing I tried and numerous times.
 

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Discussion Starter #13
well I guess the panel has to come apart; I tried the drill trick. beyond that I guess I take it in. but I cringe at the $75/hour at the local electric motor rewinding shop
 

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Kevin posted the drill trick and another using a magnet to re-energize a generator awhile back. Can't find the thread but you might look around for it.

Mike
 

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Might try "flashing" it with a 12V battery before hauling it in for a check up..maybe the drill isn't putting enough juice to the fieilds to magnetize them..

I use an old 110V cord ,hook the battery to the two wires,get the generator running and just plug it in and unplug it as soon as you hear the engine bog down as the generator kicks in,its usually almost instantly--DONT leave it plugged in too long,as 110V AC will go in the battery,and that will be dangerous!....if it dont work then,you'll need a pro to check it out..
 

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Don;

Post a picture or two of the generator end. If it's got a cover over the brushes. Pull the cover and take a pic. The procedure to diagnose this and see where you're at isn't complicated, just need a few details

Scott
 

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Somebody gave me a Chicago Electric generator model 91213 from Harbor Freight. It has the Chinese Jiangdong 5.5 Honda clone engine, which starts and runs like a top, but the generator produces no output. Tried flashing the field using the electric drill trick, but no luck. One thing, this is a brushless generator, does that make any difference?

Anyway, I took my trusty Craftsman electric drill, plugged it into the running genset, flipped it to forward, and turned the chuck backwards as fast as I could by hand, and nothing happened. Just out of curiosity, I decided to check the output of the drill and see if it was indeed producing voltage. So I attached my digital voltmeter to the power plug of the drill and chucked my DeWalt cordless drill to the Craftsman. Pulled the trigger and let the DeWalt run the corded drill as fast as it could. The output on the meter never got over 2.2 volts! What a disappointment, surely 2.2 volts isn't enough? So maybe I should try the 9V battery trick instead? Seems strange to plug a 9V DC battery into a 120V AC outlet, but I'll try anything once.
 

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I''m wondering if the electronics in the variable speed control won't let voltage pass through from the motor to the plug when the motor is turned by hand (even if the trigger is pressed).
 
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