9-12,000 watt Portable Standby Generator Recommendations

[Flintknapper]

I'm resurrecting my own thread from a year ago.

One thing I've learned about is Bonded Neutral versus Floating Neutral Generators.

Maybe it's not a common issue, looks like it can be an issue if both the Generator and the connection are bonded when connected as a "whole house" feed?

Two bonds can make for some unexpected charges/electrocution from the generator itself?

Sounds like a Floating Neutral is the preferred?

EDIT - a while back on this thread @Flintknapper was kind enough to post a photo of his generator.

I now notice it's labelled as "Neutral Bonded to the Frame." Not sure if good or bad.

View attachment 117103

My genset also has a ground 'lug' that can be used to attach the frame to a grounding rod (driven 5' into the ground). This helps provide a low resistance path to ground in the event of 'stray voltage'. And that is how I used it when powering my house panel.....prior to getting a whole house stand by generator.

But yes, it is important to understand the difference in a Bonded Neutral and Floating Neutral. When and where each is most appropriate and some of the caveats.

Bonded Neutral vs Floating Neutral in Generator

Our guide explains Bonded Neutral vs Floating Neutral in Generator differences, applications (backup power, home connection), and choosing the right one. Ensure safe and reliable generator operation!

www.electronicshub.org

 

[RBsingl]

NEC doesn't allow for the neutral to be bonded to ground at two separate points so to meet code if you have a bonded neutral generator, the transfer switch needs to also switch the neutral lead from the genset.

My diesel standby generator is mounted remotely in the barn and it uses a floating neutral setup with the generator neutral permanently bonded to neutral in the rest of the electrical system. The generator frame is separately grounded to a group of ground rods which are bonded to the common ground system.

Whether to use bonded or floating neutral depends upon the installation. Once the decision is made (sometimes made for you by the generator manufacturer) then the transfer switch and specific wiring connections must be correct for the choice.

Rodger

 

[RCW]

Okay guys - - You've all been so helpful.

Spurs more questions as I learn. Please bear with me.

I'm going with an appropriate "Inter-Lock" kit like mentioned in my other thread. Transfer Switch for Generator Power in Outages | OrangeTractorTalks - Everything Kubota

Not what I'm getting but an example. Genny cannot direct feed the panel lest the Main is OFF.

Generator Interlock Kit Collection Compatible With Square D Generator Interlock Kit For Homeline 150 And 200 Amp Panels 1-3/8 Inch Space Between Main & Generator Breaker,temu

That will take care of the 50A feed to the panel......4-wire @ 6 gauge. 2-hot, ground and neutral.

I have a new (15 years ago) installation of a 200A- 40-space Square D Homeline Panel with proper ground rods, etc. Neutral is bonded there.

Don't want two locations bonded....

Our contractor has done many. It's not an issue of the direct feed/interlock that concerns me as much as the proper generator.

I'll need a Floating Neutral Generator for that, correct?

What about the other 120 or 240v connections on the generator?

We have 2 freezers and a refrigerator in our garage.

I envisioned plugging our freezers, garage lighting, etc. in separately from the extra 120 outlets on the generator.....

Is that an issue if the genny is floating neutral?

I know some generators have GFCI 120v outlets....

I appreciate your great advice....

 

[RCW]

Moving back to the top. House renovations coming next couple weeks.

Haven't picked out a generator, but have medicine cabinets solid...

I'll try to summarize where I'm at concisely:

• Will do an 50A "Interlock" in Load Center/Service Panel to accommodate generator connection. Appears NEC compliant and prevents "back feeding" with Main on. Chosen over a transfer switch. Allows more latitude for active circuits.

• QUESTION 1: I want a Floating Neutral generator to connect 50A to the interlock? New Service: House is properly grounded, etc. Alternative is grounding a Bonded Generator. Not preferred when in an emergent situation.

• QUESTION 2: Can a Floating Neutral generator be a hazard if running "self-contained" appliance like a refrigerators, freezers, or welder? Expect the 240v/50A feed to run concurrent with use of multiple 120v outlets on the generator to run some appliances, like freezers...Do some accommodations need to be made for those 3-wire 120v connections? (Some/many 120v outlets are GFCI on the generators....)

Thanks much. Look forward to some more great advice.

 

[RCW]

Want to partially close the loop on this project.

Generator delivered yesterday. Haven't even put oil in it yet.

Contractor is due anytime for second bathroom project. Connection to the house will be part of that project.

Genny is 12,000 watt/9,500 gasoline or 11,400/9,025 propane. Doubt I'll use propane, but it is an option.

It is a floating neutral. Should be good for the 50A (4 conductor) connection to the house and has an option to ground if needed.

 

[Smokeydog]

Preparing for power outages with my pto genset has eliminated them!….so far. Do enjoy the low maintenance aspect.

Do have combination of small or large portable generators that have helped the past decades.

 

[RCW]

Will close the loop a little more.

Generator plug installed and a cord ready to go.

House plug. At the end of our patio. Good spot.

Cord - only 15 feet long, but I can make a longer one if need be.

Generator side 50A

House side to plug

 

[RCW]

Okay, this is going to be fini….

Going to be windy next couple days so did a test run of the generator.

All worked great. Interlock on the breaker box prevents generator from feeding load center with main on.

Generator ran the whole house. Of course big loads like dryer and wall ovens were off.

At 12kw, generator engine barely changed when putting load on it.

I also checked a couple outlets to make sure they were working properly, which they were.

Happy with the results.

 

[D2Cat]

Now you're ready for whatever mother nature throws at you!! Has to be some peace of mind.

 

[RCW]

Now you're ready for whatever mother nature throws at you!! Has to be some peace of mind.

You bet. Real easy switch-over to the genny. It took the limited load with barely a noticeable change in engine noise. No way my old 5,500w could have done it.

2022 was a real challenge; we had 4 outages that had us without power for a total of 9 or 10 days