# Generator N-G bonding verification question



## JMapes (9 mo ago)

I attempted to verify if my generator has the N-G bond but getting information that seems to me is conflicting. It's from early-mid 2000s and I don't have the manual and can't find a label on it about bonding. It's the standard gas type that does straight 120v. (NOT one of those weird 60v hot and N out of phase.)

Nothing connected, not running, I set multimeter to Ohms and get 0L (no line) between N and G. Then I start it and measure AC volts between hot and N I get 120v (as expected). Strangely, from hot to G I also get 120v, which I expected to see 0v. I don't quite understand. Would anyone help elaborate what I am missing?


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## sdowney717 (12 mo ago)

"Strangely, from hot to G I also get 120v, which I expected to see 0v."

EVERY Gen better see 120v from hot to ground, otherwise what use is the ground wire for protecting people from electric shock.
If an appliance plugged into gen has a ground fault with the device metal outside electrified to hot potential and the ground had no connection to allow hot current to short to ground, like a broken ground wire, the entire device is live with power, so if you are touching it and then touch the gen, you complete the circuit and are shocked, and maybe dead.

A ground wire is not normally a current carrying wire, but a neutral wire is as it completes the circuit.
I would have expected a 0(L) ohm reading between the neutral and the ground wires.


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## JMapes (9 mo ago)

I agree but I don't understand how that's happening since I see 0L (no line) when measuring ohms from N to G. What did I miss?


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## sdowney717 (12 mo ago)

JMapes said:


> I agree but I don't understand how that's happening since I see 0L (no line) when measuring ohms from N to G. What did I miss?


Maybe this gen has a relay that connects ground to neutral only when it is producing power.

What are the ohms between neutral and ground measured when it is running?

Personally I think such a thing introduces a potential unsafe condition, cause what if that fails?


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## sdowney717 (12 mo ago)

https://samlexamerica.com/wp-content/uploads/2019/12/13009-0614_NeutraltoGroundSwitchinginRVandMarineApplications.pdf



Does this help? Kind of tired, past my bedtime.


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## JMapes (9 mo ago)

I'm wondering if this is normal and I am just showing my inexperience with a multimeter. In any unbonded system would you see 120v between the hot and ground? It would just mean there is a difference in voltage potential, which is the case regardless of bonding. Can someone confirm if I got that straight?


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## OrlyP (Oct 19, 2021)

Does the generator have an ON/OFF breaker? Was it turned ON when you did the continuity testing between N-G?

It's possible that the bonding is at a point before the breaker. Since you're measuring stuff at the receptacles, that's already downstream of the breaker. Some bonds are done immediately inside the stator so N-G at the receptacles are open when the breaker is off, but becomes bonded as soon as you switch on the breaker.

Not saying this is it, but just one possible explanation.


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## sdowney717 (12 mo ago)

I looked into a lot of this years ago when I got my boat which has shore power and an Onan gen hard wired, and I was replacing my transfer switching. Of course neutral and ground are permanently bonded in the generator control box. Meaning the connecting wires from the transfer switch into the box have white neutral and green ground attached together inside of it.

So I was wondering and realized finally, the transfer switch switches both hot AND neutral together, as in when on shore power the hot AND neutral wire coming from generator are completely disconnected, and will never carry any current. So the ground wire which is common to the whole AC system, gen and shore power is remaining contiguous and fully functional. The gens white neutral wire simply becomes just another ground wire.

AND also the grounding system is not needed, it is only a safety ground wire to aid against electric shock, and it is also not good enough at stopping that risk which is why GFCI was invented, and GFCI works pretty good at lowering the shock hazards but of course it is not perfect. GFCI will shock you if your body is part of the circuit and your body is ungrounded, the detection cutoff is 5 milliamps. Hold the hot in one hand, the neutral in other of a GFCI protected circuit and you can be killed if current cant return some other way so as the GFCI breaker to detect a current leakage and turn off the power.

GFCI breakers also do not need a ground connection to function.


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## sdowney717 (12 mo ago)

I think also in a 120/240 vac system, the neutral has to be grounded or not open circuit as the voltages can fluctuate up and down on the 120v sides.


Open Neutral: Voltage Fluctuation and Stray Voltage – Voltage Disturbance


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## sdowney717 (12 mo ago)

And think about your portable generator connected to a home distribution panel with an interlock breaker setup and the neutral and ground wires. The gen has no ground rod of its own, but when connected to the home AC system, the home ac system has 2 ground rods pounded deep into the ground, so it does then have ground rods by way of it connecting wire which has a ground wire inside.
The interlock only switches the hot wires, neutral wires are not switched, this is considered ok as it is a portable temporary source of AC power, and the portable gen has no ground connection to the earth, rubber wheels and all that except by way of the ground wire back to the house ground system. (is what I think is the reason)
The ground to neutral connection is only in the distribution panel. If the gen was always the source of power, then the ground to neutral bond would have to be at the generator. The goal is I suppose in not creating ground loops where some current is always flowing through the ground back to its source. Which is possible if the neutral wire has high resistance, and you have multiple ground to neutral bonds in many places. Which if the generator has no ground rod of its own, cant happen.


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## JMapes (9 mo ago)

sdowney717 said:


> And think about your portable generator connected to a home distribution panel with an interlock breaker setup and the neutral and ground wires. The gen has no ground rod of its own, but when connected to the home AC system, the home ac system has 2 ground rods pounded deep into the ground, so it does then have ground rods by way of it connecting wire which has a ground wire inside.
> The interlock only switches the hot wires, neutral wires are not switched, this is considered ok as it is a portable temporary source of AC power, and the portable gen has no ground connection to the earth, rubber wheels and all that except by way of the ground wire back to the house ground system. (is what I think is the reason)
> The ground to neutral connection is only in the distribution panel. If the gen was always the source of power, then the ground to neutral bond would have to be at the generator. The goal is I suppose in not creating ground loops where some current is always flowing through the ground back to its source. Which is possible if the neutral wire has high resistance, and you have multiple ground to neutral bonds in many places. Which if the generator has no ground rod of its own, cant happen.


Few things:

1) To connect a generator that has an N-G bond to a house main panel you cannot use a interlock kit. You need a 3-pole transfer switch that also cuts the neutral wire and both hots. It is termed a "separately derived system."

2) Generators with no N-G bond are "non separately derived" and basically are just an extension of the main breaker panel. This is where you could use an interlock kit or a 2-pole transfer switch. And there is no need to add any ground rods.

3) It's not about the neutral wire having high resistance or something. It's about paths back to the source. Current will take all available paths simultaneously in parallel. If you have multiple N-G bonds in the system then some amperage will take white/neutral back to source, and some will take the ground wire. Some portion on one and some portion on the other. Obviously dangerous and must be avoided by following the previous 2 points.

At this point my original question technically remains unsolved but after sleeping on this I am feeling pretty sure I have an unbonded generator (no N-G bond).


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## pipe (Jun 27, 2021)




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## JMapes (9 mo ago)

pipe said:


>


Yes pipe I saw that vid. It doesn't explain why I see AC voltage when I put my multimeter probes going from hot to ground. That's my lingering question at the moment.


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## sdowney717 (12 mo ago)

I just measured my gens for a neutral to ground bond.
The TroyBilt, no neutral to ground bond.
The Generac, has a neutral to ground bond. I already new it did when I looked at the wiring diagram online.

I have used both for interlock panels over the years.
Disconnecting the frame bond wire on the Generac does not break the neutral to ground bond, and how could it, as the thing is bonded inside the receptacle - breaker box itself, deliberately hard wired that way from what I recall noticing.


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## GenKnot (Dec 20, 2021)

JMapes said:


> It doesn't explain why I see AC voltage when I put my multimeter probes going from hot to ground.


That should not be happening if the gen has a floating neutral configuration.

A floating neutral generator will read no voltage between the frame and neutral or between the frame and hot. (Note: You may read some voltage if the gen is running because the rotating magnetic fields may induce a little bit of current into the frame, but it is of no concern when it comes to safety.) You will also read no continuity between the frame and neutral or hot. For a floating neutral generator, both sides of the current carrying conductors are considered hot.

So, if you are reading 120V between the frame/ground and hot, then the gen is bonded.

Here is an example of a floating neutral configuration...









Notice that the ground conductors on the receptacles are connected to the frame, and there is also an Earth Terminal provided to connect to a ground rod. But nowhere is the frame/ground and the neutral (W) connected. To convert this gen to a bonded neutral a wire would be necessary between the ground and neutral wiring.


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## JMapes (9 mo ago)

Sdowney for my sanity do you mind starting both generators once and setting your multimeter to AC volts please? Nothing plugged into either one, just stand alone. And please do both since you said one is bonded and one is not, that gives a good comparison between both styles. How many volts do you get from hot to ground on each one? If the number you see on the meter seems strange please provide it anyway as it's displayed on the meter.


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## sdowney717 (12 mo ago)

JMapes said:


> Few things:
> 
> 1) To connect a generator that has an N-G bond to a house main panel you cannot use a interlock kit. You need a 3-pole transfer switch that also cuts the neutral wire and both hots. And besides that you are supposed to give the generator its own ground rods, as it is termed a separately derived system.
> 
> ...


3) * It's not about the neutral wire having high resistance or something.*
From another forum this in response to number 3 in your post,
"Your* neutral current will split* and run down both the neutral and ground* based on their resistance*."
I already said that too.








Bonded Generator & Interlock Kit


Ok I have a quick question that ive been going blind with all the different answers. I have a Square D Panel with a Square D interlock kit installed. My question is my Generator has a Bonded neutral on it. So when I hook it up it is backfeeding my panel to my 30A breaker and the Main...




www.electriciantalk.com


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## sdowney717 (12 mo ago)

There is no problem with an interlock kit and a neutral bonded generator.

*Note from moderator: The post, and forum member cited, are from another forum not affiliated with Power Equipment Forum. Take the post for what it's worth.*


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## JMapes (9 mo ago)

sdowney717 said:


> View attachment 11406
> 
> 
> There is no problem with an interlock kit and a neutral bonded generator.


Sdowney yes it will technically work but it's unsafe, incorrect design, and a code violation. Just like running the generator indoors, works fine, but hazardous. So, for that generator (N-G bonded) you are supposed to simply plug devices direct to the generator with extension cords. That's it. Or if you really want to connect it to your main panel you need a 3-pole transfer. That way you avoid the scenario of multiple N-G bonds in the same system. Posting a good article on this below.

By the way I'm not insulting anyone that plugs in their generator when it's below 0 degrees to heat their home, even if it's a code violation. You gotta do what you gotta do. Just saying if you can plan in advance with safety in mind then that's the way to go. Actually that's why I started this forum thread with my first post.

Do you mind seeing my last post before this one? I'd really appreciate if you would be willing to run that test and share your readings.









Connecting Your Portable Generator in a Derived System


Connecting Your Portable Generator in a Separately Derived or Non-Separately Derived System




www.trystar.com




.


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## JMapes (9 mo ago)

GenKnot said:


> That should not be happening if the gen has a floating neutral configuration.
> 
> A floating neutral generator will read no voltage between the frame and neutral or between the frame and hot. (Note: You may read some voltage if the gen is running because the rotating magnetic fields may induce a little bit of current into the frame, but it is of no concern when it comes to safety.) You will also read no continuity between the frame and neutral or hot. For a floating neutral generator, both sides of the current carrying conductors are considered hot.
> 
> ...


Measuring Ohms I have 0L (no continuity) between neutral and ground though. When I start the generator I've got to be seeing phantom voltage or something due to not having a real load on it. Nothing plugged in besides multimeter. I feel pretty confident generator is unbonded and there must be some logical explanation for the hot-to-ground voltage reading.


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## GenKnot (Dec 20, 2021)

JMapes said:


> When I start the generator I've got to be seeing phantom voltage or something due to not having a real load on it.


Quite possible that you are seeing a phantom voltage. You could find out by installing a wire between ground and neutral (in other words bonding it) and then start the gen. If a breaker does not trip then everything is fine. That would mean you currently have an unbonded gen.


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## sdowney717 (12 mo ago)

ANY power switching is ok as long as the generator output is not GFCI protected, bonded or not bonded neutral it is OK.

So either one of my two gens, since the 120/240 vac outlet is not GFCI protected, it wont be tripping any breakers.
And of course it does not. Everything works fine.

If the output panel of the generator is full on GFCI protected, then output breaker on the gen will trip off when switching power, means you have to also switch the neutral then, so a different kind of switch, an interlock in the panel wont work for such a generator.

Solution is dont buy full GFCI output panel generators. Which honestly you dont need. Downstream GFCI protection from the distribution panel onwards is where most people have electrical shock exposure.

And I wonder if this could work, switch the interlock FIRST in the panel, then turn on the output breaker on the generator. Too bad, I have no way to test that.


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## sdowney717 (12 mo ago)

__
https://www.reddit.com/r/Generator/comments/lw2vjo

AND in CANADA the Interlock panels for generator connection are illegal, unless they switch the neutral wire. As I have no intention of EVER living in Canada, not a concern. But some people on this forum might live in Canada. They have their own electric codes and we in the USA have our own electric codes.


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## GenKnot (Dec 20, 2021)

The Reliance switch that he refers to in the video has a third pole that switches the neutral. So, it works okay with a bonded gen (and GFCIs) and would be considered a separately derived system.





XRC0303D X Series - Reliance Controls Corporation


XRC0303D X Series - Reliance Controls Corporation - Manufacturers of Transfer Switches and Panels for Portable Generators. Toll-Free Information (800) 634-6155. Product details,manuals, install video and information,vendor locator,product selector,troubleshooting,product support




www.reliancecontrols.com





















Note the difference in the gen bonding, the switching of the neutral conductor, and the ground rods.


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## sdowney717 (12 mo ago)

GenKnot said:


> The Reliance switch that he refers to in the video has a third pole that switches the neutral. So, it works okay with a bonded gen (and GFCIs) and would be considered a separately derived system.
> 
> 
> 
> ...


Yes, well I have no plans to do any changes. I prefer my interlock setup from Square-D

I designed my boats system, and switch the neutral along with the hot wires using two 30 amp 4 pole double throw cascading relays. Works fantastic for years now.

I welded up this box myself

















This is the basic idea, I can switch from 3 different power sources to one output










I did find though that activating the relay coils on 120vac, cause marina power can be poor quality, they may buzz. So i drive them using 17v DC current instead of 120v AC current.
Since DC is steady they are absolutely silent, even if marina power falls off.

Did that using 2 wall warts and voltage divider to modify the voltage.
I also can control these relays at the helm with regular small toggle switches, now driven by low voltage DC, it is very safe setup. I have to switch twin 30 amp shore power lines, so needed 4 pole relays. My boat is not 240vac anything. But sure someone could adapt to about anything desired, like 240 vac power.


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## JMapes (9 mo ago)

sdowney717 said:


> ANY power switching is ok as long as the generator output is not GFCI protected, bonded or not bonded neutral it is OK.
> 
> So either one of my two gens, since the 120/240 vac outlet is not GFCI protected, it wont be tripping any breakers.
> And of course it does not. Everything works fine.
> ...


Bud, I think we speak different languages. Your argument seems to be that if you kick it on and a breaker doesn't trip then it works and it's fine. If it does trip, like a GFCI, then just swap the GFCI with non-GFCI. I hope I'm not misrepresenting your advice.

Unfortunately I don't feel safe stopping there. Actually the system I'm looking at working on has been "cowboyed" by my grandpa for 40 years and I am coming in to straighten it out and make it safe. There is a cabin with a regular NEMA 5-15R wall outlet (like you'd have inside your living room) directly on the exterior and in full exposure to the elements, with buried UF-B cable (who am I kidding it's probably nm-b) coming directly out of the ground (no conduit) plugged into that outlet with a NEMA 5-15P plug. Not even a plate or any attempt at covering. The birds and squirrels can see the live wires in plain view.

Yeah... someone who cares about understanding safe electrical work needs to put some effort into that cabin (I guess that's going to be me). That's why I posted - to try to make this safer for my family/grandpa. So getting everything planned first before I begin. Sdowney do you mind running the hot-to-ground test with your multimeter on AC Volts to both your running generators please and posting the results?


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## sdowney717 (12 mo ago)

I get the feeling some of you really dislike Interlock breakers in main panels, well that is just your opinion, too bad for anyone listening in to the nonsense.

I already linked to an electric forum, where the consensus was it was fine to do it.

BESIDES that, we have people coming in here asking very elementary questions, then saying they are experts?

*Note from moderator: The post, and forum member cited, are from another forum not affiliated with Power Equipment Forum. Take the post for what it's worth.*


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## sdowney717 (12 mo ago)

Not going to put gas in either gen just to run a test, then have to drain it all out again.

Is there an ignore poster feature on this forum?


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## JMapes (9 mo ago)

sdowney717 said:


> I get the feeling some of you really dislike Interlock breakers in main panels, well that is just your opinion, too bad for anyone listening in to the nonsense.
> 
> I already linked to an electric forum, where the consensus was it was fine to do it.
> 
> BESIDES that, we have people coming in here asking very elementary questions, then saying they are experts?


My question has nothing to do with interlocks even remotely, nor have I up to this point offered any opinion on them. I did provide documentation to you that links to OSHA and NEC code since you brought up the topic. I'm not the electrical expert; I am an engineer in an entirely different field. I trust OSHA and NEC as the electrical experts. If you found a forum where the consensus was to reject OSHA and NEC code I would stop there and move on.

With that out of the way, yes actually I like your idea to use a manual interlock method for boats, since you are already manually connecting and disconnecting everything else and in full control of where the electricity is flowing.

That's probably the single most annoying thing for me about a manual interlock bracket during a power outage at home (completely different scenario), in that you have no idea when power restores without getting out your binoculars and seeing if the neighbors have lights on. You don't necessarily want (or care) about having your thumb on controlling the power. My first house was like that. My second house had a 13kwh Generac with an automatic transfer switch and worked automatically. Much more convenient. In my third house now which has no power redundancy (except a small battery backup I installed for my sump) but no power outages so far in 8 months so maybe I won't install anything further for now (maybe solar someday).

Are you willing to run the test I asked? We don't have a consensus on the expected (versus actual) hot-to-ground voltage for N-G bonded versus non-N-G bonded systems, which is the OP...


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## Powergen (10 mo ago)

Excuse me for hijacking this thread. I'm no expert and was needing guidance on my gen setup. My Gen is neutral bonded and I don't think my panel is where my two pole 30amp gen breaker is when using this breaker in my square D panel. I have two separate neutral and ground locations and no green ground screw in this panel. I do have another breaker box outside by the meter for the pool pump etc, it may be grounded there.. Would I be ok using this setup the way it is with my neutral bonded GEN?
















I will include pics of what I have and any advice would be greatly appreciated.


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## JMapes (9 mo ago)

sdowney717 said:


> Not going to put gas in either gen just to run a test, then have to drain it all out again.
> 
> Is there an ignore poster feature on this forum?


Ignore poster? You know, you responded to my thread in the first place, and didn't answer the question. You say the answer is "elementary". I agree it probably is. Nevertheless there is still no consenses yet.

If I find the answer before someone else posts it here I'll follow back up in good faith to the others who may be following or refer back to this in the future. Thanks.


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## sdowney717 (12 mo ago)

Powergen said:


> Excuse me for hijacking this thread. I'm no expert and was needing guidance on my gen setup. My Gen is neutral bonded and I don't think my panel is where my two pole 30amp gen breaker is when using this breaker in my square D panel. I have two separate neutral and ground locations and no green ground screw in this panel. I do have another breaker box outside by the meter for the pool pump etc, it may be grounded there.. Would I be ok using this setup the way it is with my neutral bonded GEN?
> View attachment 11414
> 
> View attachment 11413
> ...


You unbonded panel seems to be a subpanel then? And the outside breaker panel is the main panel. If so, the panel is setup fine.

SO AGAIN here read this with electricians talking about bonded gens and interlocks.








Bonded Generator & Interlock Kit


Ok I have a quick question that ive been going blind with all the different answers. I have a Square D Panel with a Square D interlock kit installed. My question is my Generator has a Bonded neutral on it. So when I hook it up it is backfeeding my panel to my 30A breaker and the Main...




www.electriciantalk.com





*Note from moderator: The post, and forum member cited, are from another forum not affiliated with Power Equipment Forum. Take the post for what it's worth.*


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## sdowney717 (12 mo ago)

Gen Interlock on sub panel


I have a Service that has a 150A Breaker Enclosure for Service Main on the outside of building and a 200A Sub Panel inside building with Main lugs only. Can I install another 150A mainbreaker kit in Subpanel to be able to use Mechanical Interlock Kit from Interlock for back feeding a 2pole 50A...



forums.mikeholt.com




Here is a Mike Holt discussion on the very subject. And that site is also well moderated by good electricians

*Note from moderator: The post, and forum member cited, are from another forum not affiliated with Power Equipment Forum. Take the post for what it's worth.*


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## JMapes (9 mo ago)

Powergen said:


> Excuse me for hijacking this thread. I'm no expert and was needing guidance on my gen setup. My Gen is neutral bonded and I don't think my panel is where my two pole 30amp gen breaker is when using this breaker in my square D panel. I have two separate neutral and ground locations and no green ground screw in this panel. I do have another breaker box outside by the meter for the pool pump etc, it may be grounded there.. Would I be ok using this setup the way it is with my neutral bonded GEN?
> View attachment 11414
> 
> View attachment 11413
> ...


You have a main panel (N-G bonded) at the first service disconnect (where the electric company drops a few heavy gauge wires to you) connected to a sub panel (not N-G bonded again there but relying on the single existing bond at the main disconnect). Adding a generator that has an N-G bond would be a separately derived system. If you see a few posts back, GenKnot posted about this already in this thread, 6 posts before your post (post # 24) 

See 1926.404(f)(3) and onward:





1926.404 - Wiring design and protection. | Occupational Safety and Health Administration







www.osha.gov





And also:





eTool : Electric Power Generation, Transmission, and Distribution - Hazardous Energy Control - Protective Grounding and Bonding | Occupational Safety and Health Administration







www.osha.gov


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## GenKnot (Dec 20, 2021)

Powergen said:


> Would I be ok using this setup the way it is with my neutral bonded GEN?


That would be considered a separately derived system. The neutral would need to be switched, or you can remove the N-G bond at the gen. See the drawings in post #24.
You can only have N-G bonded in one place in a system. Your subpanel does not have N-G bonded because the main panel would have it.


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## GenKnot (Dec 20, 2021)

Oh, I see that JMapes and I were replying at the same time.


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## JMapes (9 mo ago)

Hey Powergen does your generator breaker bracket actually "interlock"? The point of that metal bracket around it is to physically block anyone from potentially having the 200A top breaker and the generator 30A double breaker switched on simultaneously. It's supposed to mechanically ensure one is on, or the other (or both off). Doesn't look to be the case, maybe it's my eyes?


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## Powergen (10 mo ago)

I was hoping I wouldn't have to tear into my gen control panel to disconnect the neutral bond, thinking my sub panel was ok for a neutral bond gen. eventhough it was neutral bonded at the outside main meter panel. Like I said I'm no expert. I will just have to remember to reverse it back to neutral bonded when I use it out in the field. Thanks everyone.


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## Powergen (10 mo ago)

JMapes said:


> Hey Powergen does your generator breaker bracket actually "interlock"? The point of that metal bracket around it is to physically block anyone from potentially having the 200A top breaker and the generator 30A double breaker switched on simultaneously. It's supposed to mechanically ensure one is on, or the other (or both off). Doesn't look to be the case, maybe it's my eyes?


Yes it interlock. There is no way to have the main breaker on and gen breaker on at the same time. The breaker cover has the interlock on it. Not shown in the pic


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## GenKnot (Dec 20, 2021)

Powergen said:


> I was hoping I wouldn't have to tear into my gen control panel to disconnect the neutral bond, thinking my sub panel was ok for a neutral bond gen. eventhough it was neutral bonded at the outside main meter panel. Like I said I'm no expert. I will just have to remember to reverse it back to neutral bonded when I use it out in the field. Thanks everyone.


Some people faced with that situation put a heavy duty switch on their gen to go back and forth on the N-G Bond. Just remember to label everything clearly. A generator that has been modified from its factory condition should always be labeled as such.


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## JMapes (9 mo ago)

Powergen said:


> I was hoping I wouldn't have to tear into my gen control panel to disconnect the neutral bond, thinking my sub panel was ok for a neutral bond gen. eventhough it was neutral bonded at the outside main meter panel. Like I said I'm no expert. I will just have to remember to reverse it back to neutral bonded when I use it out in the field. Thanks everyone.


Would you be able to locate and post the correct manual and/or wiring diagram for your specific generator? We can take a look.


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## Powergen (10 mo ago)

GenKnot said:


> Some people faced with that situation put a heavy duty switch on their gen to go back and forth on the N-G Bond. Just remember to label everything clearly. A generator that has been modified from its factory condition should always be labeled as such.


Thats a great idea. Any suggestions on a heavy-duty switch? It would make it easier going from neutral bond to not by having this. Run a heavy guard wire to the switch and mount the switch somewhere on the gen. Any suggestions?


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## Powergen (10 mo ago)

JMapes said:


> Would you be able to locate and post the correct manual and/or wiring diagram for your specific generator? We can take a look.


Not sure how to share the link to the owners manual. I can share pics though LOL. This is the Gen I have. Appreciate the feed back.


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## GenKnot (Dec 20, 2021)

JMapes said:


> Would you be able to locate and post the correct manual and/or wiring diagram for your specific generator? We can take a look.


Powergen has a Champion 100520.


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## GenKnot (Dec 20, 2021)

Oops, did it again. Posting at same time, but this time with Powergen.


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## JMapes (9 mo ago)

Powergen said:


> Thats a great idea. Any suggestions on a heavy-duty switch? It would make it easier going from neutral bond to not by having this. Run a heavy guard wire to the switch and mount the switch somewhere on the gen. Any suggestions?


Alternatively I have seen numerous stories of people who choose an unused receptacle on their generator and make a homemade bonding plug to insert which shorts the neutral and ground wires.

Here's an example video below for a NEMA 5-15P but you could do the same thing for a NEMA L5-20P for example. Personally I would go with this option so I could fully reverse the generator back to "factory" in case you ever needed to, for example if you were in a pinch and might be easier to sell it that way. Also seems easier to perform the modification... just need a blank plug and a short piece of 12 gauge solid copper to make the bonding plug.

Disclaimer, I've never done this, just sharing what I've seen.


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## GenKnot (Dec 20, 2021)

👆 Yes, those plugs work great too. You just have to remember to take it with you.

Or a switch...maybe something like this:








Amazon.com: DaierTek Safety Cover Toggle Switch Guard ON Off 2 Pin Red Aircraft Covered Rocker Switch 20A 12VDC / 120VAC Heavy Duty SPST for Car Truck Automotive : Automotive


Buy DaierTek Safety Cover Toggle Switch Guard ON Off 2 Pin Red Aircraft Covered Rocker Switch 20A 12VDC / 120VAC Heavy Duty SPST for Car Truck Automotive: Toggle - Amazon.com ✓ FREE DELIVERY possible on eligible purchases



www.amazon.com


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## JMapes (9 mo ago)

Powergen I looked at your manual. It simply shows the neutral plugs connected with a line going to all the ground plugs, right at the receptacles. When you open the unit up, the neutral to ground bonding jumper might be physically located right at one of the receptacles, just like the schematic shows. I posted a Youtube video below from them for a similar model generator to yours (in that case it's an unbonded model) which shows the same thing. It also looks like the manufacturer may be willing to offer advice/support if you call.

Additionally noticed your generator outlets appear to be GFCI. Once you remove the bonding jumper I am not sure if the outlets will work correctly (I wouldn't even try) until you restore some manner of neutral-to-ground bonding in the system. Once you connect up to your house it should make it work effectively same as factory again.

Take good pictures and notes and store them safely so you remember how to reverse any modifications in 10 years from now when you've forgotten.


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## GenKnot (Dec 20, 2021)

JMapes said:


> Additionally noticed your generator outlets appear to be GFCI. Once you remove the bonding jumper I am not sure if the outlets will work correctly (I wouldn't even try) until you restore some manner of neutral-to-ground bonding in the system. Once you connect up to your house it should make it work effectively same as factory again.


The GFCIs should still work because they measure the difference between the two current carrying conductors (hot & neutral). The test button won't work without ground, but that function should be restored once the gen gets connected up to the house as you mentioned.


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## Powergen (10 mo ago)

Thanks guys👍, I will take this information and decide which would work for me.


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## JMapes (9 mo ago)

Hope the info helps. Do us a favor though and come back and give an update when it's all done.


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## motormonkey (Jul 10, 2016)

When determining what is acceptable electrical practice, the FIRST place to look for reference is the NATIONAL ELECTRICAL CODE (or its equivalent in the country you're in) and NOT posts on an internet forum from people who may or may not know what they're doing.


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## somedumbguy (Sep 17, 2020)

JMapes said:


> I attempted to verify if my generator has the N-G bond but getting information that seems to me is conflicting. It's from early-mid 2000s and I don't have the manual and can't find a label on it about bonding. It's the standard gas type that does straight 120v. (NOT one of those weird 60v hot and N out of phase.)
> 
> Nothing connected, not running, I set multimeter to Ohms and get 0L (no line) between N and G. Then I start it and measure AC volts between hot and N I get 120v (as expected). Strangely, from hot to G I also get 120v, which I expected to see 0v. I don't quite understand. Would anyone help elaborate what I am missing?


JMapes ... From what you have said about the measurements you took, I believe your generator does have the neutral bonded to the frame of the generator, and that the "ground" terminal of any outlets on the generator are also connected/bonded to the frame. How are you going to use this generator? (1) Using outlets on the generator to run extension cords to your house bypassing the in home electrical systems to power your TV, Fridge, etc (2) As a portable to power loads outside while camping or using outdoor tools and lawn equipment, etc, or (3) to feed your house electrical system through its circuit panel box.? Deciding if the bonds should be altered depends on if you choose 1, 2, or 3.


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## JMapes (9 mo ago)

somedumbguy said:


> JMapes ... From what you have said about the measurements you took, I believe your generator does have the neutral bonded to the frame of the generator, and that the "ground" terminal of any outlets on the generator are also connected/bonded to the frame. How are you going to use this generator? (1) Using outlets on the generator to run extension cords to your house bypassing the in home electrical systems to power your TV, Fridge, etc (2) As a portable to power loads outside while camping or using outdoor tools and lawn equipment, etc, or (3) to feed your house electrical system through its circuit panel box.? Deciding if the bonds should be altered depends on if you choose 1, 2, or 3.


In my case I'm planning to revamp the electrical strategy for an offgrid cabin, and to install a solar system that includes a battery. This is a couple of months out yet (solar panels and battery on back order), and in the mean time learning all I can about safe electricity and really getting my head wrapped around this stuff.

Today the cabin has a neaby building with a 4500W generator with a L14-30R outlet protected with a 30A "pop-out" breaker (built into generator) runnin 50 feet (underground, detached structures) directly into a really really old subpanel in the trailer with lugs and fuses (no main breaker, and yes actual fuses). When the generator is in a 240V mode (basically it always has been used that way) the L14-30R has the hot-X and hot-Y plugs wired to separate coils in the generator (look up Honda 4500EX). Those correspond to the separate lugs in the trailer subpanel, which each have 2 fuses (and dedicated circuits, 4 total) connected to them. If you switch the generator to 120v mode it kills the hot-Y and basically half the appliances in the trailer stop working (as intended).

When I disconnect all plugs from the generator (and turn off the generator) and connect my multimeter to neutral and other probe to ground I get 0L (no connection). I believe I can simply stop there and conclude yes it's unbonded neutral. While the trailer is "unplugged" from the generator (no power anywhere inside the trailer) if I probe ground to white wires I get 0 Ohms. I don't see in the sub panel where they're shorted to each other (ground and white), and not intentionally bonded from what I can tell. So going to work on solving that mystery this weekend. Obviously they are connected someplace, I may have to disconnect cables one at a time and keep testing to narrow possibilities and isolate. Once I locate that bond, the long term plan will be to remove (relocate) it, at the same time I do all the other changes.

Planning to replace all the lights in the trailer to LED which will reduce the maximum continuous concurrent load from 3537W to 2776W (measured using a cheap "6 Function Mini Digital Clamp Meter" purchased from Harbor Freight) and then I'll kick the generator from 240v mode to 120v mode. This disconnects the hot-Y from that L14-30R totally from all other conductors inside of the generator, and flips all the other "hot" plugs to connect in parallel and they all share both main windings in the generator. Everything in the trailer runs off of just 120v so it's fine. Then I will wire nut off the hot-Y (which will no longer be hot) and disconnect it from the panel. Then I'll bridge both hot lugs in the trailer sub panel with a 6awg THHN, so essentially all 4 fuses will be running off of the same single hot-X conductor in the L14-30R which is powered by both windings. Should run better that way, and will set the stage for my solar rig which will be strictly 120v.

Final setup will be 2 series of 3 parallel solar panels, terminating to 2x 15 amp DC breakers in a combiner box, and then to a 3500W Renogy 48V solar inverter. Inverter will have a 5.12kWh battery attached (with a built-in breaker). Generator will also connect directly to the AC-IN lugs (hot, neutral, ground) on the Renogy. Then Renogy hands off AC-OUT (hot, neutral, ground) to a new main panel I will install (where the Neutral-Ground bonding will occur) coming into a 30A single pole AC breaker, and then another separate 30A single breaker toward the trailer. Renogy will limit AC charging (from generator) to 5A with a setting I'll input (to avoid overcurrent on the feed from generator). Will also have another 15A breaker in main panel so we can have a circuit for the outbuilding - might connect a 25W incandescent bulb to keep from freezing in the winter.

So it's important to me that I eliminate all other points this old system may be bonded so the single bonding can occur at the new main panel with the 30A breakers.


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## OrlyP (Oct 19, 2021)

Late to the party and apologies if I missed it in one of the previous posts but, what is the make/model of the generator in question?


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## JMapes (9 mo ago)

OrlyP said:


> Late to the party and apologies if I missed it in one of the previous posts but, what is the make/model of the generator in question?


Chassis says Honda EX 4500 and when I look at the bar code it says EX4500SK1A. Also just for the record the manual says unbonded neutral BUT I really don't trust manuals from overseas companies like Honda.


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## OrlyP (Oct 19, 2021)

JMapes said:


> Chassis says Honda EX 4500 and when I look at the bar code it says EX4500SK1A


From what I can gather from the schematic is that the EX4500S has an unbonded Neutral. 

Do you get any voltage read between N-G when the generator is running? 

If N-G is 0V, do you get any continuity between them (again with generator running)? Of course, do not do continuity tests between N-G if the voltage across them is higher than 0V.


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## JMapes (9 mo ago)

OrlyP said:


> From what I can gather from the schematic is that the EX4500S has an unbonded Neutral.
> 
> Do you get any voltage read between N-G when the generator is running?
> 
> If N-G is 0V, do you get any continuity between them (again with generator running)? Of course, do not do continuity tests between N-G if the voltage across them is higher than 0V.


Did some reading and apparently you can sometimes see above 0V on multimeter even when it really is 0V. Supposed to switch multimeter to "LoZ" (low impedence) to see if it shows 0.00V in that mode, which my cheap-o multimeter doesn't have. So I have to make due without being able to fully trust my voltage reading. Good suggestions though, thank you, going to try this.


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## OrlyP (Oct 19, 2021)

JMapes said:


> Did some reading and apparently you can sometimes see above 0V on multimeter even when it really is 0V. Supposed to switch multimeter to "LoZ" (low impedence) to see if it shows 0.00V in that mode, which my cheap-o multimeter doesn't have. So I have to make due without being able to fully trust my voltage reading. Good suggestions though, thank you, going to try this.


Yeah, I guess you can say that under 1V is just stray voltage from proximity and coupling effect but still essentially considered 0V.


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## GenKnot (Dec 20, 2021)

JMapes said:


> Strangely, from hot to G I also get 120v, which I expected to see 0v.


I agree that the gen is unbonded, but how is the opening comment about reading 120V from hot to ground explained?


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## GenKnot (Dec 20, 2021)

@JMapes Just FYI... If you happen to run into issues with the Renogy inverter rejecting the generator, it will probably be a THD issue. I received this information from MPPT Solar a few months ago when I was asking them some questions about their inverter. I would suspect that Renogy may have the same response.


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## JMapes (9 mo ago)

GenKnot said:


> I agree that the gen is unbonded, but how is the opening comment about reading 120V from hot to ground explained?


It might not have been 120v. I really need to measure again. But there was definitely a voltage reading from the multimeter. So I saw some numbers "yep 120v" and moved on. I'll be up there this weekend (cabin is a fair drive away) so I can double check.


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## GenKnot (Dec 20, 2021)

JMapes said:


> It might not have been 120v. I really need to measure again. But there was definitely a voltage reading from the multimeter.


Okay, that would change everything. An unbonded gen would read 0V between Ground and either Hot or Neutral. You may see some small, induced voltage as I stated in post #15.


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## somedumbguy (Sep 17, 2020)

GenKnot said:


> I agree that the gen is unbonded, but how is the opening comment about reading 120V from hot to ground explained?


Good question GenKnot. JMapes; when you were taking these initial measurments was the generator, running or not, connected to the cabin panel in some way via the L14-30 outlet? Does the cabin electrical system have a grounding system? Is the neutral of the old fuse panel bonded to a true ground? Remember that once you connect the L14-30 cable, the ground of the "house" wiring comes into play. am not familiar with "off-grid" electrical systems for cabins; is it truly off-grid and never has utility power? You mention a trailer and nearby building. You need to understand how/if the neutral and ground wires are connected in these structures and if/how there is a true earth ground built into the system.


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## JMapes (9 mo ago)

somedumbguy said:


> Good question GenKnot. JMapes; when you were taking these initial measurments was the generator, running or not, connected to the cabin panel in some way via the L14-30 outlet? Does the cabin electrical system have a grounding system? Is the neutral of the old fuse panel bonded to a true ground? Remember that once you connect the L14-30 cable, the ground of the "house" wiring comes into play. am not familiar with "off-grid" electrical systems for cabins; is it truly off-grid and never has utility power? You mention a trailer and nearby building. You need to understand how/if the neutral and ground wires are connected in these structures and if/how there is a true earth ground built into the system.


Generator had no cables plugged into it at all. There definitely is a ground-to-neutral connection somewhere in the trailer (intended or not) which I still need to find - project for this weekend. Well aware of that. But no the generator had nothing plugged in. I'll take a more careful series of measurements this weekend.


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## JMapes (9 mo ago)

GenKnot said:


> @JMapes Just FYI... If you happen to run into issues with the Renogy inverter rejecting the generator, it will probably be a THD issue. I received this information from MPPT Solar a few months ago when I was asking them some questions about their inverter. I would suspect that Renogy may have the same response.
> View attachment 11452


Hmm yes my generator is a traditional alternator generator and not inverter style. Now this has me thinking if it would be beneficial from a waveform perspective to run the generator in 120v mode versus 240v mode. Wonder if it's cleaner running on one winding versus both. I may just have to try both ways. Will be as easy to test as flipping a switch.


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## sdowney717 (12 mo ago)

Another interesting discussion from a high posting electrician on the site mentions that there already exist multiple ground to neutral bonds coexistent with your home's distribution panel, such as at the utility power poles and of course all along your street. I don't recall grounding my meter panel when I installed a new meter base a few years ago, so the second other connecting neutral to ground bond exists at my utility power pole about 75 feet away.









Portable generator question


Thanks everyone, got the Reliance inlet box and the QO lockout installed, going the order the genny next! Which model generator?




www.electriciantalk.com




Take a look at Post #24
-------------------------------------------------------------------------------------------------------
And then the mention of nuisance shocking. And this mention of very little current actually flows through the earth ground between them, I do of course understand the reason for why it is done. I also know people like to follow written codes and rules. If your just going to criticize, dont bother responding,



https://forum.nachi.org/t/ground-and-neutral-bonded-at-service-box/24636


"The neutral wire from the utility is also* grounded* at the pole and other locations (e.g. the neighbors service). The earth actually does become a parallel path for current, however the impedance (resistance) is so great compared to the neutral circuit wire, that very little current actually flows through the ground. (due to multiple neutral to ground bonds, i.e., your home service entrance)"


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## JMapes (9 mo ago)

sdowney717 said:


> Another interesting discussion from a high posting electrician on the site mentions that there already exist multiple ground to neutral bonds coexistent with your home's distribution panel, such as at the utility power poles and of course all along your street. I don't recall grounding my meter panel when I installed a new meter base a few years ago, so the second other connecting neutral to ground bond exists at my utility power pole about 75 feet away.
> 
> 
> 
> ...


Hey SDowney give this Mike Holt video a watch from 15:42 to 17:12. If you think it's interesting you may like to enjoy the whole video. It's a good one.





In short you need a main bonding jumper between neutral and ground at your main electric panel to provide a very "short" and direct path for current to take via ground, back to neutral, so there will be enough amps to trip your breaker. I think if your electric company already has a jumper that's very very closeby you may be able to safely lack any jumper on your end and just rely on theirs, but I believe the determining factor there may be if there is an actual ground wire running directly (unspliced wire) from your main electric panel straight to their equipment where the jumper is. I am honestly not sure, actually that sounds expensive. Of course if you lack that wire and just connect to your ground rod, and the power company connects to their ground rod, there's no way those ground rods (just dirt, no direct wire) will be enough to trip your breaker.

At my house all the power company drops to me is 2 hots and a neutral. They don't give me a ground wire from their transformer box. So in my case if I had no N-G bonding jumper at my house I would effectively have absolutely no N-G bonding at all in my system. This is regardless of what the power company is doing, it doesn't matter how many N-G bonds they have if I'm not connected to those, my breaker is just not going to trip. But yes the electric company has neutral to ground jumpers all over the place, at least 5 of them every mile of power lines, and in some cases many more than that.

Also worth noting the post #24 you referenced was made by a banned account. The problem with that post in particular is called "objectionable current" and I have no idea if that has anything to do with what got them banned, but again worth nothing. Banned accounts aren't the first place I look for advice.

Let me pose you this question. If you see no problem with sending current over your ground wires on purpose (objectionable current), why use white wires at all? Might as well just replace all of your white wires with bare copper, and short them to the "ground" terminals also. Connect bare copper to all of the silver lugs on your outlets, and the ground lugs, and bond them to all the metal chassis throughout your home. The metal framing for your toaster is essentially now a big "neutral" white colored wire.

It's exactly the same situation when you have N-G bonds in both your main panel and in your generator, using an interlock only (not switching neutral with a 3-pole switch), and while running on generator power (utility switched off). In that example, your whole generator frame is a big (LIVE) white wire, as well as the bare copper wire running from your generator to main electric panel. So just to walk through the current flow it goes: Generator -> black/red wire -> main electric panel -> parallel paths via white wire (and ground via main bonding jumper at service disconnect) -> generator neutral terminal (and generator ground wire, chassis, neutral-ground bond, and finally to neutral terminal). If you can't see how that's dangerous, then I would be curious to see the volt and amp readings on your generator ground wire while everything in the house is running. I imagine if you have everything running off generator and you stand in a puddle in the rain and touch the generator you could get a shock. Actually seems like a scenario it would be very dangerous for you to have a good ground rod installed for your generator, that would be almost certainly fatal.

Hey SDowney I had to read this again... actually in your case I'm just assuming you don't have a ground wire running from your panel to your utility pole. So again assuming that, the power company gives you 2 hots and a neutral, correct? So you effectively have no bonding jumper besides the generator? That doesn't sound right. In that case, though, if you had a ground fault that would have to transit your generator through probably 10 gauge wire with enough amps to trip your breaker. Still that's definitely not right but at least you do technically have only one N-G bonding point I guess? I would be curious to hear what an inspector would say about that. I imagine they would say the main bonding jumper belongs at the service disconnect instead of at the generator. Let me see if I can find the code...


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## JMapes (9 mo ago)

This should solve -

250.24 (5) Load-Side Grounding Connections. A grounded conductor shall not be connected to normally non-current-carrying metal parts of equipment, to equipment grounding conductor(s), or be reconnected to ground on the load side of the service disconnecting means except as otherwise permitted in this article.

250.30 Informational Note No. 1: An alternate ac power source, such as an on-site generator, is not a separately derived system if the grounded conductor is solidly interconnected to a service-supplied system grounded conductor. An example of such a situation is where alternate source transfer equipment does not include a switching action in the grounded conductor and allows it to remain solidly connected to the service-supplied grounded conductor when the alternate source is operational and supplying the load served.


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## motormonkey (Jul 10, 2016)

JMapes said:


> This should solve -
> 
> 250.24 (5) Load-Side Grounding Connections. A grounded conductor shall not be connected to normally non-current-carrying metal parts of equipment, to equipment grounding conductor(s), or be reconnected to ground on the load side of the service disconnecting means except as otherwise permitted in this article.
> 
> 250.30 Informational Note No. 1: An alternate ac power source, such as an on-site generator, is not a separately derived system if the grounded conductor is solidly interconnected to a service-supplied system grounded conductor. An example of such a situation is where alternate source transfer equipment does not include a switching action in the grounded conductor and allows it to remain solidly connected to the service-supplied grounded conductor when the alternate source is operational and supplying the load served.


Yes, that should solve, along with one additional piece of information. 

2020 NEC, Article 250.30(A)(1) System Bonding Jumper. An unspliced system bonding jumper shall comply with 250.28(A) through (D). This connection shall be made at any single point on the separately derived system from the source to the first system disconnecting means or overcurrent device, or it shall be made at the source of a separately derived system that has no disconnecting means of overcurrent devices,in accordance with 250.30(a)(1)(a) or (b).


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## GenKnot (Dec 20, 2021)

👆 Precisely (post #69), and that matches up with the diagram...










One of the biggest things (IMO) that confuses people are the words "grounded conductor" and "grounding". *Grounded conductor* (for our purposes) is referring to the neutral wire. *Grounding* refers to the equipment ground wiring (aka EGC) that is earthed in the system and also bonded (at only one point) to the neutral in the system.

If there is no switching action in the grounded conductor (neutral) through the transfer equipment/switch, then the generator system remains grounded with the transfer switch in either position (normal or standby) by the grounding electrode conductor at the service.


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## somedumbguy (Sep 17, 2020)

GenKnot said:


> ..
> One of the biggest things (IMO) that confuses people are the words "grounded conductor" and "grounding". *Grounded conductor* (for our purposes) is referring to the neutral wire. *Grounding* refers to the equipment ground wiring (aka EGC) that is earthed in the system and also bonded (at only one point) to the neutral in the system.


GenKnot ... Yes, that has certainly confused me more than a few times. I still have a hard time reading these code-speak things because my brain is so busy translating "grounded" to neutral and "grounding" to "ground" that I can't keep my mind on the main point of their sentence. I've always assumed that they don't like to use the term "neutral" because a neutral/white wire can easily become hot if there is a loose/broken connection. (I learned that the hard way)!


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## JMapes (9 mo ago)

somedumbguy said:


> GenKnot ... Yes, that has certainly confused me more than a few times. I still have a hard time reading these code-speak things because my brain is so busy translating "grounded" to neutral and "grounding" to "ground" that I can't keep my mind on the main point of their sentence. I've always assumed that they don't like to use the term "neutral" because a neutral/white wire can easily become hot if there is a loose/broken connection. (I learned that the hard way)!


Could you elaborate a little more on the loose/broken connection causing a neutral/white to become hot? Still learning and trying to visualize what you mean.


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## GenKnot (Dec 20, 2021)

I know exactly what he is referring to. I have been shocked many times by such a scenario...








Break in wire or loose connection at wire nut in neutral wire.


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## JMapes (9 mo ago)

Makes perfect sense. Thanks.


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## iowagold (Jan 22, 2020)

it is all about reference!
what state of charge you are comparing to.
so make sure to use the one gloved hand and insulated shoes!
"when in doubt check it out!"
always check for voltage!
or lock out the main panel as source when opening up a wiring panel or box

always check for voltage!.


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## somedumbguy (Sep 17, 2020)

iowagold said:


> it is all about reference!
> what state of charge you are comparing to.
> so make sure to use the one gloved hand and insulated shoes!
> "when in doubt check it out!"
> ...


absolutely. The tricky thing about electricity is even if a circuit appears to work OK, that doesn't mean it was wired correctly/safely. The well known example is a light fixture with the switch on the neutral wire rather than the hot wire. That works fine, but is a shock hazard if someone is changing the bulb, even if the switch is turned off. I owned an older house which didn't have any grounding at the wall outlets. (I believe that was very common back-in-the-day). And the outlets were daisy-chained on circuits without any regard to proper polarity. That's a shock hazard too, especially if someone starts replacing the outlets with modern polarized plugs without correcting the polarity issues in the wiring.
Sorry to get so far off topic, JMapes, but it sounds like you are getting into a very complicated project. If I was involved in something like that, I wouldn't assume that anything that is already in place was originally done properly/safely by today's standards, especially an older property, one involving multiple buildings, or where you have reason to think DIYers did some of the wiring. (I am a DIYer)!


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## iowagold (Jan 22, 2020)

always consult electrical code!
and follow and upgrade to match the latest is the best plan.
and also watch the fire code regulations as well.

insurance needs things to be right for good coverage.

it might cost a bit more up front but.
in the BIG picture but keeping up to code is cheaper...
and a few years down the road it is a good thing when you go to sell the property!
it is worth more if it is up to with in 5 years of current code.

safety first on all of this stuff!


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## JMapes (9 mo ago)

Well here are my exact readings from today. Still not sure what to make of. Nothing plugged into generator, no ground rod, nothing, just completely isolated. Hoping you guys will have a field day with this. Also not sure if it matters but my multimeter is a INNOVA 3320 I always put the red probe on the "hotter" of the 2 terminals being tested (in order hot > neutral > ground) and black on the other terminal.


Generator NOT running: 120V mode

L14-30R
Ground to Neutral reads 0L Ohms (no continuity)

L5-30R
Ground to Neutral reads 0L Ohms (no continuity)


Generator NOT running: 240V mode

L14-30R
Ground to Neutral reads 0L Ohms (no continuity)

L5-30R
Ground to Neutral reads 0L Ohms (no continuity)


Generator RUNNING: 120V mode

L14-30R
Ground to Neutral reads 0L Ohms (no continuity)
Ground to Neutral reads 46.9 Volts AC
Ground to Hot (Red "X", actual hot) reads 69V
Ground to Hot (Black "Y", switched off in 120 mode) reads 1.7V
Hot (Red "X") to Neutral reads 120.7V
Hot (Black "Y", switched off in 120 mode) reads 7V

L5-30R
Ground to Neutral reads 0L Ohms (no continuity)
Ground to Neutral reads 46 Volts AC
Ground to Hot reads 69V
Hot to Neutral reads 120V


Generator RUNNING: 240V mode

L14-30R
Ground to Neutral reads 0L Ohms (no continuity)
Ground to Neutral reads 8 Volts AC
Ground to Hot (Red "X") reads 124.4V
Ground to Hot (Black "Y") reads 109.9V
Hot (Red "X") to Neutral reads 120.9V
Hot (Black "Y") reads 121.1V

L5-30R
Ground to Neutral reads 0L Ohms (no continuity)
Ground to Neutral reads 8 Volts AC
Ground to Hot reads 110V
Hot to Neutral reads 120.9V


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## OrlyP (Oct 19, 2021)

JMapes said:


> Well here are my exact readings from today. Still not sure what to make of. Nothing plugged into generator, no ground rod, nothing, just completely isolated. Hoping you guys will have a field day with this. Also not sure if it matters but my multimeter is a INNOVA 3320 I always put the red probe on the "hotter" of the 2 terminals being tested (in order hot > neutral > ground) and black on the other terminal.
> 
> 
> Generator NOT running: 120V mode
> ...


Based on that, I'm now certain it's unbonded.

The Hot to Ground voltage readings are likely just induced voltages and will probably have a high impedance. If you're up to it, can you put a test incandescent light bulb across Hot and Ground? That'll tell us if current will actually flow. But don't get your Hot feed from a GFCI outlet (if equipped) as it will just trip doing this test.


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## GenKnot (Dec 20, 2021)

The readings look like they are probably normal for that machine. I am a bit surprised that you did continuity readings on a running gen though. Ohm readings are usually done on de-energized circuits...sometimes the meter goes up in a puff of smoke otherwise.

One test that you can do is to put in a N-G bonding plug and see if the voltage readings look more like normal grid voltages...they should. With a floating gen voltage readings can look pretty wonky from a ground reference point.

Since you are rebuilding the electrical system at the cabin and including solar, I am sure you are trying to get a reliable system in place. I would consider replacing this gen with an inverter type so as to gain fuel efficiency and future-proof against possible issues with electronics too (for example, the Renogy inverter may not like this gen). Take a look at the WEN units. They are reasonably priced and usually there is no shipping or tax if ordered from their website. If you don't mind a pull start, the 6250/5KW WEN GN625i is hard to beat. You could sell the current gen to help offset the cost or keep it as a backup.


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## JMapes (9 mo ago)

GenKnot said:


> The readings look like they are probably normal for that machine. I am a bit surprised that you did continuity readings on a running gen though. Ohm readings are usually done on de-energized circuits...sometimes the meter goes up in a puff of smoke otherwise.
> 
> One test that you can do is to put in a N-G bonding plug and see if the voltage readings look more like normal grid voltages...they should. With a floating gen voltage readings can look pretty wonky from a ground reference point.
> 
> Since you are rebuilding the electrical system at the cabin and including solar, I am sure you are trying to get a reliable system in place. I would consider replacing this gen with an inverter type so as to gain fuel efficiency and future-proof against possible issues with electronics too (for example, the Renogy inverter may not like this gen). Take a look at the WEN units. They are reasonably priced and usually there is no shipping or tax if ordered from their website. If you don't mind a pull start, the 6250/5KW WEN GN625i is hard to beat. You could sell the current gen to help offset the cost or keep it as a backup.


At some point it was suggested in this discussion to do an N-G Ohm reading while generator running. Still learning so willing to try most things as long as I believe I'm avoiding personal danger. If my meter did go up in smoke it would be a nice excuse to buy a Fluke 117! _sunglasses_


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## GenKnot (Dec 20, 2021)

JMapes said:


> At some point it was suggested in this discussion to do an N-G Ohm reading while generator running.


Yeah, I know it was suggested. Not much I can say about that.


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## GenKnot (Dec 20, 2021)

"With the circuit de-energized, connect the test leads across the component being tested."








How to Test for Continuity with a Digital Multimeter


Learn how to test continuity using a digital multimeter.




www.fluke.com


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## somedumbguy (Sep 17, 2020)

jmapes; Good work. I'm trying to make sure I understand your latest test results/conditions. (It would be helpful to have a picture of the outlets on your generator). 

In your very first post, you said "Then I start it and measure AC volts between hot and N I get 120v (as expected). Strangely, from hot to G I also get 120v, which I expected to see 0v. I don't quite understand. Would anyone help elaborate what I am missing?" 

Was one of your most recent tests a repeat of that first test? (Where were you probing in that very first post and what was the 120/240 position? Was it a standard onboard 120 outlet? the L14-30 outlet? or the L5-30 outlet? ) Your first post implies (to me) a bonded generator but the latest imply floating. You think the first was just a mistake? (Been there, done that)!

What I'm really getting at is that at some point you are going to want to focus in on the configuration(s?) you actually intend to use when you are all done and make sure that the gen is delivering what you want.

Also, when the generator is connected to the cabin, the readings may be different. For example, when/if the L14--30 configuration is used to power the cabin, the cable running to the building panel will end up connecting the ground and neutral together at the generator, even if they are not already as appears to be the case with a floating neutral generator. At least that is how a house with a service panel would be wired. (Does something different happen with off-grid wiring or with solar)?


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## JMapes (9 mo ago)

somedumbguy said:


> jmapes; Good work. I'm trying to make sure I understand your latest test results/conditions. (It would be helpful to have a picture of the outlets on your generator).
> 
> In your very first post, you said "Then I start it and measure AC volts between hot and N I get 120v (as expected). Strangely, from hot to G I also get 120v, which I expected to see 0v. I don't quite understand. Would anyone help elaborate what I am missing?"
> 
> ...


The original test was on the L14-30R with generator running in 240V mode from Ground to Hot (Red "X") and read approximately 120V (latest test measured exactly 124.4V) which we are now chalking up to induced voltage.

Final configuration will have the panel inside the cabin as a sub panel, with no bonding between neutral and ground. A main panel will be mounted near the generator which will have a neutral-ground bond and a couple of ground rods running to it. Everything above ground bonds to the main panel ground, which then connects to the ground rods.

The neutral-ground bond has to exist somewhere in the system in one place. This provides a low resistance path so the ground connection can be used as a return current path in the event of a fault to trip breaker and automatically switch to a safe state (breaker flipped off). Same idea as on-grid house wiring.


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## OrlyP (Oct 19, 2021)

GenKnot said:


> Yeah, I know it was suggested. Not much I can say about that.


Was that me?

Did left a caveat that the voltage needs to be zero before testing for continuity.... in case there's some weird logic in the genhead or control panel that switches between bond and unbonded depending on whether it's running or not.


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## GenKnot (Dec 20, 2021)

OrlyP said:


> Was that me?


Nope.


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## somedumbguy (Sep 17, 2020)

OrlyP said:


> Was that me?


Maybe it was me. I asked a question about the readings jmapes was getting and used the phrase "running or not". Maybe that implied it was OK to test continuity that way. That wasn't what I meant but I can see how it might be interpreted that way. Sorry.


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## GenKnot (Dec 20, 2021)

somedumbguy said:


> Maybe it was me.


Nope.


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## JMapes (9 mo ago)

Wired a hot-ground test incandescent. Tested in my kitchen and popped GFCI. Tested on another outlet and lit up just fine. Then drove to cabin and tested on generator (stand alone, nothing else plugged) and did not light! Plugged in cabin and it lit right up. Additionally, found a bonding screw in the cabin fuse box - just a plain screw (not green). Confirmed with multimeter when I removed that screw there was no bonding in the system. Restored that for time being until I install the new panel and convert the existing panel into a sub-panel. Thanks everyone for your help with this. Learned some things.


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## OrlyP (Oct 19, 2021)

It's great you finally got to the bottom of things.


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