# home generator problem

**URL:** https://boards.straightdope.com/t/home-generator-problem/388182
**Category:** Factual Questions
**Created:** [January 16, 2007, 12:20pm UTC](https://boards.straightdope.com/t/home-generator-problem/388182 "2007-01-16T12:20:23Z")
**Posts on this page:** 5
**Page:** 1

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### Author: ![aruvqan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aruvqan/32/2891_2.png) [@aruvqan](https://boards.straightdope.com/u/aruvqan)
#### Post date: [January 16, 2007, 12:20pm UTC](https://boards.straightdope.com/t/home-generator-problem/388182/1 "2007-01-16T12:20:23Z")

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A friend of ours just got a used generator in a swap, and it worked once, then it wouldnt ‘flash the field’ [whatever that is…]

Is this something that can be fixed at home or does it need to go to a repair place?

It is a Powerguard 3000 - they asked mrAru because he knows how to flash the field on a submarine generator but this is _quite_ a bit dofferent =)

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### Author: ![Uncommon\_Sense](https://avatars.discourse-cdn.com/v4/letter/u/f9ae1b/32.png) [@Uncommon\_Sense](https://boards.straightdope.com/u/Uncommon_Sense)
#### Post date: [January 16, 2007, 1:53pm UTC](https://boards.straightdope.com/t/home-generator-problem/388182/2 "2007-01-16T13:53:09Z")

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[Google search for; generator “flash the field”](http://www.utterpower.com/Trouble.htm)  
I recommend that your friend calls the manufacturer and talks to a service rep before continuing though.

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### Author: ![gotpasswords](https://avatars.discourse-cdn.com/v4/letter/g/c57346/32.png) [@gotpasswords](https://boards.straightdope.com/u/gotpasswords)
#### Post date: [January 16, 2007, 4:30pm UTC](https://boards.straightdope.com/t/home-generator-problem/388182/3 "2007-01-16T16:30:04Z")

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How used is the genny? I’ve never heard of Powerguard, and it’s sounding like this is a no-name, orphaned import cheapie - around here, some of the auto parts places sell basic small generators for around $200. They usually wear labels like

3000 Wattspeak output

but in reality can only sustain about half that for any length of time.

If your friend’s into tinkering, it might be worth messing with, but otherwise, the fellow on the other side of the swap just might have come out ahead this time. 😛

How did they manage to diagnose this, anyway? Is there an idiot light that says “Field is unflashed” or is it simply not putting out any power? If it’s not making power, there may simply be a bad connection inside - I know this from experience and it’s reminding me that my own generator needs to be opened up so I can fix a loose wire. :smack:

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### Author: ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)
#### Post date: [January 16, 2007, 4:38pm UTC](https://boards.straightdope.com/t/home-generator-problem/388182/4 "2007-01-16T16:38:49Z")

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[Flashing the generator exciter field](http://www.dieselduck.ca/library/tech_notes/flashing_generator.htm):

> [@](#):
>
> Residual magnetism in the generator exciter field allows the generator to build up voltage during start-up. This magnetism is sometimes lost due to shelf time or improper operation, among other reasons. Restoring this residual magnetism is possible and is sometimes referred to as “flashing the exciter field”.

> [@](#):
>
> 1. Remove exciter field leads F+ and F- from the voltage regulator. CAUTION: Failure to remove the field leads from the regulator during flashing procedures may destroy the regulator.
> 2. Measure the exciter field resistance from the F+ to the F- lead. You should be able to read some resistance as you are measuring a continuous winding. An infinite resistance reading would indicate an open in the exciter field. Also check to be sure there is no path to ground.
> 3. Connect F+ to the positive pole of the battery.
> 4. Hold the F- lead by the insulated portion of the lead wire, touch F- to the negative pole of the battery for about 5 to 10 seconds, then remove.
> 5. Reconnect F+ and F- to the regulator. Repeat the procedure if the generator fails to build voltage.

If this doesn’t work, then there is another problem, possibly a broken conductor or burned out component or any number of other possibilites.

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### Author: ![aruvqan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aruvqan/32/2891_2.png) [@aruvqan](https://boards.straightdope.com/u/aruvqan)
#### Post date: [January 17, 2007, 12:11am UTC](https://boards.straightdope.com/t/home-generator-problem/388182/5 "2007-01-17T00:11:34Z")

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Well, mrAru has 20 years experience with generators in the navy - though as he pointed out they are much larger and way more expensive=) and he did various PMS-y type checks with arcane tools I have no working knowlege of … and he is convinced the field needs flashing. On the huge ship generators it is very well known and accessable, he is just not entirely certain what to do on tiny itty bitty civillian generators. I did google, extensively - and apparently the powr guard brand is actually extant [it has some sort of honda gas engine and is actually very solidly built, not cheap and manky thin metal and plastic]

I am just trying to help him help out Drew=)

Thanks for the suggestions=)
