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Powering tools via a generator

Carol Reed said:
OK, Ryan. If I understand correctly, I should make the 'Edison" plug referred to in the link. It is simply a plug with a wire from the neutral to the ground plug lugs. I should plug it into any one of the 20 amp outlets. And label it as a GND to Neutral bond plug.
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That appears to be the recommendation. I'm only sort of happy with that for a couple of reasons:
  1. I'm not positive that the 120v outlet ground and neutral are 100% the same same as the ground/neutral on the 220v outlet. Please cross check that there is continuity between the 220 neutral and the 120 neutral and the same for the ground.
  2. I don't know the wire sizes inside the generator, are the wires for 120 outlet adequately sized for providing the neutral<->bond for the higher voltage 220 circuit? No idea.

So in general I'd be happier if the bond was actually done with some sort of bonding plate or ? inside the generator - but I have no idea how to do that.

Having said that it appears that (assuming that it does provide the bond as checked by item #1 above and of course cross checking that neutral and ground have continuity in the 220v outlet after plugging the "edison" plug in) it appears to be the "best" solution otherwise.

Carol Reed said:
Second, I should make sure that my distribution panel in the trailer is grounded to the frame of the trailer.
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While you are testing continuity make sure the skin of the trailer has continuity to the frame. I can't imagine how it wouldn't.. but we're here with a continuity tester and it will take less than a minute.

Carol Reed said:
Third, I should make sure that the ground of the genset's 30 amp outlet is grounded to the frame of the genset.

And that is all I should do. This should properly and safely allow the genset to power the trailer's distribution panel. The other genset outlets will be marked out of service.
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As I understand it yes :D

Carol Reed said:
That said, I am unsure how to verify the floating neutral the label on the genset says the 30 amp outlet is.
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You should be able to verify that with a continuity tester between the neutral and the ground plugs on the generator. If they have continuity between the two outlets then they are bonded. If they do not have continuity they are not.

Carol Reed said:
Finally, my assumption is when the genset is running I should measure 120VAC between each 'hot' and neutral. I should measure 0 volts from neutral to ground. And 0 volts from hot to ground. Am I right? Before I smoke anything.
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Correct except the hot->ground which will be 120v (the ground is an alternative return path if there is a short so its required to conduct the electricity). There may be some small voltage between ground and neutral (less than 2v-3v anything more is concerning; there can be potential voltage difference between any two wires of sufficient length - ask me sometime about wiring low voltage in tall buildings.. icky).
There is a nice diagram details the testing points and acceptable voltages here: http://www.noshockzone.org/rv-electrical-safety-part-iii-–-outlets/

Carol Reed said:
This far a search for a locally intelligent person on this subject has been fruitless, but I am not done looking.

And the education continues.
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I do wish you luck on your venture finding someone local, that would make us all a lot happier I believe!! It seems that this is a source of vast confusion even for many qualified electricians and they simply follow the rules as written without understanding any of the potential trade offs which is rather terrifying when you think about it (there are a lot of rules.. does everyone get them ALL right? what about the exceptions they sometimes matter as well).

Anyway please stay safe when testing! Glasses and rubber boots are recommended!
 
Carol Reed said:
And the education continues.
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I'm Mike Sokol, author of www.NoShockZone.org and electrical safety expert. I'm the guy who developed the G-N generator bonding plug mentioned in this thread, and dozens of RV users have emailed me that it works properly for their own RV generators. Even if you already have an internal G-N bond inside your generator, this plug should not harm anything. You'll want to plug it into any non-GFCI outlet on the generator itself, then you can use your 240-volt outlet to power the RV.

Note that the NEC does not require portable generators under 5KW to be G-N bonded, nor do they require them to be earth grounded. I think for most RV and portable power tool applications, adding a G-N bond is the best idea. That keeps your ground and neutral at the same potential and standard outlet tester will read this as correctly wired. Even if you have a floated Neutral, your capacitor-start motor should still be OK since the safety ground wire is never connected to the motor windings, only the frame of the motor itself.

Please contact me at mike@noshockzone.org for clarification if you need it.

Mike Sokol
www.NoShockZone.org
 
Wow, thanks, Mike. I am honored you weighed in! And thanks to Ryan for staying with me. I have a meeting tomorrow all day, but on Wednesday I plan to implement my three steps and measure accordingly. Now I need to find an adapter to connect my 50amp cord from the trailer's distribution panel to the 30amp twistlock outlet on the genset. Time to Google it.

Thanks again, guys. I will post my results.
 
Carol Reed said:
Wow, thanks, Mike. I am honored you weighed in! And thanks to Ryan for staying with me. I have a meeting tomorrow all day, but on Wednesday I plan to implement my three steps and measure accordingly. Now I need to find an adapter to connect my 50amp cord from the trailer's distribution panel to the 30amp twistlock outlet on the genset. Time to Google it.

Thanks again, guys. I will post my results.
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If it were me... I would simply make a custom cord with the proper ends, the parts for which I believe can all be obtained at the local home despot. You could alternatively make a short patch cord, but imho the fewer connection points in a circuit the better off you are.
 
Not cheap, Ryan. Finally found an adapter - $46 on Amazon. Individual parts probably would be as much. This one is nicely sealed. A shop made version is not worth it to me, though I could. Whatever might be saved would be miniscule and my version would not be sealed as this one is. So it is on order.

Shoot, the 35 foot 50 amp RV cord was nearly $150! And its bare end is terminated in the distribution panel.
 
Carol Reed said:
Open leg on the 220v outlet. Can't find any help on-line. Suggestions?
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Some gens have each leg fused separately, so check that first. Also, half your 120v~ outlets on the gen work off each leg. Are half of them dead, too? If they're okay, the problem might just be a loose connection behind the panel.

Are you sure it's dead in the generator, and not in your extension cord?
 
Round two.

Continuity checked through all legs. Don't know where the problem might have been as I dismantled the panel and removed the end cap pf the generator to do the checks. All checked out OK. No longer see an open anywhere. Could have been a loose connection. The connector from the gen to the panel is kinda sloppy. It doesn't 'click' together like I wish it did.

However. When I introduce a load on the gennie, it wants to die instead of increase RPM's to meet the load. Really only tried in on the 220v circuit because that is really the only one I need to work. Wonder what to look for now. The manuals are useless.

There is a small engine guy in town. I have talked with him before but I am not sure he knows what he is doing. There is a sparkie who is a member of the church. Hope he's planning on worshiping tomorrow. I'm gonna sandbag him afterwards.

@Jim. You are righ. Each leg is on its own breaker and half the outlets work on one leg and the others work on the other leg. Physically traced the wires, so I know.
 
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