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Portable generator floating neutral

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Bmxer883

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Location
Pa
Occupation
Industrial electrician
So I just want to make sure there is nothing wrong with my thinking. I bought a 2000w inverter generator to run my fridge or furnace with just a cord. But I didn't realize till I got it home it's a floating neutral I just made a dummy plug with jumper ground to neutral and plugged it in with the circuit. Now it should be good correct?

I have a 5000w normal generator I use to back feed house it's floating neutral but my house has a bonding point so it's good I just don't trust to run my stuff with electronics.

I deal with more industrial electric and just wanted opinions who know code and residential better than me. Thanks
 
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Bmxer883

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Location
Pa
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Industrial electrician
As long as it's safe I only use in power outage I'm saving for a whole house generator.

And yes I don't trust my cheap 5000w generator from what I read you can't trust any portable generator that's not a inverter. Even tho my parents been doing it for years now with out issue.
 
roger

roger

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Bmxer, please update your profile to include occupation and location.
 
TwoBlocked

TwoBlocked

Senior Member
Location
Bradford County, PA
Occupation
Industrial Electrician
The instruction manual should tell you how to ground the generator. Probably there is a threaded stud you run a lugged grounding wire to a ground rod with.
 
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shortcircuit2

Senior Member
Location
South of Bawstin
zbang said:
Screamingly correct? No, the bond should be inside the generator.
Functional, yes. (It provides a fault current path to trip the breaker.)
Click to expand...
Whats the difference of a floating neutral generator back feeding a home placed a distance away from the homes main service with the bond at the homes service panel?

A neutral to ground terminal jumper in a cord cap will like you say functionally create a safer fault current path for his floating neutral generator depending on what (and how) it is connected to.

I have a Honda 2100i and it is floating. I bond mine with a cord cap #10 copper jumper N-G inserted into the 120-volt receptacle on the gen-set to back-feed my trailer. All the GFCI devices work with the cord cap inserted and don't when removed.

I will have to do more research on it because I don't understand why Honda floats the neutral on them. These little portable generators are more often used at camp sites and should be bonded.

And NO...it doesn't need a ground rod...as it is used as a temporary power source.
 
Dsg319

Dsg319

Senior Member
Location
West Virginia
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Wv Master “lectrician”
What are the advantages of making these small gensets bonded instead of leaving them floating?
 
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suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
Dsg319 said:
What are the advantages of making these small gensets bonded instead of leaving them floating?
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I dont think there is any. It is an ungrounded isolated power source. A fault should not shock you. Two faults maybe, but you or the dirt need to be involved. If the genny case is plastic, that further isolates you from earth making a shock less likely. GFCI is a secondary failsafe.

A negative for bonding it at the factory is that is technically not allowed with a solid neutral transfer switch. Mist people dont have transfer switches that switch the neutral.
 
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Bmxer883

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Location
Pa
Occupation
Industrial electrician
suemarkp said:
I dont think there is any. It is an ungrounded isolated power source. A fault should not shock you. Two faults maybe, but you or the dirt need to be involved. If the genny case is plastic, that further isolates you from earth making a shock less likely. GFCI is a secondary failsafe.

A negative for bonding it at the factory is that is technically not allowed with a solid neutral transfer switch. Mist people dont have transfer switches that switch the neutral.
Click to expand...
The idea to bonding a generator would be if you wanted to use it as a portable like run power tools or something in that case you wouldn't want a floating neutral
 
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Bmxer883

Member
Location
Pa
Occupation
Industrial electrician
shortcircuit2 said:
Whats the difference of a floating neutral generator back feeding a home placed a distance away from the homes main service with the bond at the homes service panel?

A neutral to ground terminal jumper in a cord cap will like you say functionally create a safer fault current path for his floating neutral generator depending on what (and how) it is connected to.

I have a Honda 2100i and it is floating. I bond mine with a cord cap #10 copper jumper N-G inserted into the 120-volt receptacle on the gen-set to back-feed my trailer. All the GFCI devices work with the cord cap inserted and don't when removed.

I will have to do more research on it because I don't understand why Honda floats the neutral on them. These little portable generators are more often used at camp sites and should be bonded.

And NO...it doesn't need a ground rod...as it is used as a temporary power source.
Click to expand...
My thoughts exactly.. and yeah I don't care to use a ground rod really doubt it's going to get hit by lightning and that's all it's really for lol
 
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suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
Bmxer883 said:
The idea to bonding a generator would be if you wanted to use it as a portable like run power tools or something in that case you wouldn't want a floating neutral
Click to expand...
Again why? You need to change your mindset when dealing with ungrounded systems. Nothing happens to you on a single fault on an ungrounded system. If there is a second fault that doesnt cause the breaker to trip yet creates a shock hazard, the gfci is your defence.
 
TwoBlocked

TwoBlocked

Senior Member
Location
Bradford County, PA
Occupation
Industrial Electrician
I stand somewhat corrected. From an OSHA fact sheet: https://www.osha.gov/sites/default/files/publications/grounding_port_generator.pdf

"Thus, rather than connect to a grounding electrode system, such as a driven ground rod, the generator’s frame replaces the grounding electrode. If these conditions do not exist, then a grounding electrode, such as a ground rod, is required."

I stand by what I said about going by the manufacturer's manual.
 
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Bmxer883

Member
Location
Pa
Occupation
Industrial electrician
suemarkp said:
Again why? You need to change your mindset when dealing with ungrounded systems. Nothing happens to you on a single fault on an ungrounded system. If there is a second fault that doesnt cause the breaker to trip yet creates a shock hazard, the gfci is your defence.
Click to expand...
I guess I'm not understanding. What's the difference then in a old house that only has a hot and neutral are you saying that's safe then cause it's ungrounded?
 
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suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
Bmxer883 said:
I guess I'm not understanding. What's the difference then in a old house that only has a hot and neutral are you saying that's safe then cause it's ungrounded?
Click to expand...
No. Power from the power company is earthed at the transformer and is solid neutral from pole to pole so the neutral is connected to the dirt whether the house is connected to dirt or not. So a house black wire can shock you if you are standing on the ground.

If the power company transformer was completely isolated from the earth (no neutral-earth bond anywhere) then you would not be shocked if you touched the black wire in an ungrounded house. But our utility distribution systems are not this way. A floating neutral generator is.

Like I said, you need to change your thinking when dealing with ungrounded systems.
 
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suemarkp

Senior Member
Location
Kent, WA
Occupation
Retired Engineer
And I believe the grounding requirement for stand alone generators, whether floating or bonded neutral, is dissipation of static electricity. Spinning rotors in air can build up static.
 
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