Does Your EMS Shut Down When Running On a Generator?

[ncitro]

Thanks Neil.
I'm on the phone with Champion again, but likely will have to do as you suggested. I just read a Mike Sokol article online & he said some of the Chinese ones "...don’t have a floating neutral, nor do they have a bonded neutral. Instead they make 60-volts AC on the hot wire, and 60-volts AC on the neutral wire. Sorry, but I don’t have a fix for that one.".
That should be easy to check with a multi-meter.
Champion Manual says "Floating Neutral" and Champion says generator is grounded to frame inside...interesting for sure. I'm going to try a second brand new bonding plug, as maybe I got a bad plug. No idea...

Wow I would hope they are not doing that, but if they were I would think your EMS should see that as well. Hopefully its just the polarity reversed, that would at lease be fixable. I would doubt you have a bad bonding plug if you tested it as you said, I just made my own by putting a piece of wire between the two prongs inside a plug. There is no other magic there.

[Cate&Rob]

TucsonJimCate&Rob

Rob,
I'm told Jim's out of town...might you be able to offer any ideas on this??
Matt

Hi Matt,

I think you are on the right track. There is lots of confusing information from Champion on this. I would go back to basics with an ohm meter and the generator shut off and look for continuity between L & G and between N & G in all the generator output receptacles. It is possible that something wired incorrectly in the 15A outlet is screwing up the 30A outlet. If L, N and G are isolated from each other across all combinations of outlet terminals . . . this has to be something within the internal generator wiring.

Rob

[S&M_G]

Hi Matt,

I think you are on the right track. There is lots of confusing information from Champion on this. I would go back to basics with an ohm meter and the generator shut off and look for continuity between L & G and between N & G in all the generator output receptacles. It is possible that something wired incorrectly in the 15A outlet is screwing up the 30A outlet. If L, N and G are isolated from each other across all combinations of outlet terminals . . . this has to be something within the internal generator wiring.

Rob

Thanks Rob.

What I found with my multimeter set to 2M on scale & genset off:
--20amp outlet. N-G .221 L-G .238. N-L .241
--30amp RV outlet. N-G .550. L-G .548. N-L .541

Pulled the panel and inspected the wiring and outlets appear to be wired properly. Champion uses RED, BLUE, GRN/YLW for its wires. Red was wired to all "hot" ports, Blue to "neutral" and Grn/Ylw to grounds.
They had me inspect the wire harness connections to ensure all were fully seated and no wires coming out of back of connector. All good.

Champion believes it's a bad control unit or a programming fault within the control unit. Senior Technician (took 40 mins to get to him) said with a floating neutral the bonded plug should fix my issue and allow power to flow through the EPO/Surge Protector and GFI outlets to work. So....guess I will wait and see.

Question: If I had to use the generator, what would be the risk be to the RV, in addition to the obvious that we can't use a EPO/Surge Protector?

[Guest]

Champion recommends a ground rod to be connected to their external ground lug. Champion claims this will complete the bonded neutral (along with wiring mod) as long as you drive the copper rod 8ft into the earth???? Jims bonding adapter would be easier if you don't mind giving up one outlet.

I use an external EMS which is not used with our Champion 3500 Inverter generator when boondocking.

Can't carry 8ft of copper pipe to every boon docking site so I may consider a shorter piece of copper.

https://www.youtube.com/watch?v=_qVR5Yvktlk&t=85s

Jim

[TedS]

There is no need to connect the generator chassis ground the earth, the dirt. You don't want that electrical path through the earth. Imagine touching a hot line while you were standing on the electrically connected dirt. You would be a path for current flow, shock.

[Guest]

There is no need to connect the generator chassis ground the earth, the dirt. You don't want that electrical path through the earth. Imagine touching a hot line while you were standing on the electrically connected dirt. You would be a path for current flow, shock.

Ted,

Champion recommends this where honestly I have not used it. However maybe Champion is recommending the earth ground because the generator chassis is un-grounded where a second ground path is needed? This would be the only earth ground in the system as described in the video Howard posted. Perhaps a live generator chassis would be really bad.
Since I run the generator from the back of the truck at times, maybe this condition provides additional protection.
Jim

[TedS]

I believe that ground lug on the generator is connected to the generator chassis which is electrically connected to the generator.

Operating out of the truck would not need the ground lug be connected to anything. The truck is electrically isolated from the dirt. The generator floating neutral mode will work, the trailer ems will not. Bonding neutral to ground will work, so will the trailer ems.

On edit: changed gfci to ems.

[Jlawles2]

I wonder if either the bonding plug or the receptical on the generator is wired backwards??? If the bonding plug is improperly made (bonded hot to neutral), this is a direct short and will trip overload every time.

If comfortable working around electricity, verify the hot and neutral are on the correct legs. Then check the bonding plug again, i've made the mistake and seen it made several times on unmarked plugs to get 2 of the items reversed when looking at the backside b/c the diagram was from the other side.

[Guest]

Portable Generators with/without Bond to Neutral is a hard to wrap my head around, like why are companies allowed to build them that way.
The standards seemed to have different views about it.
ANSI/PGMA G300-2018 Safety and Performance of Portable Generators
ANSI/UL 2201 Mitigates Carbon Monoxide (CO) Poisoning for Portable Generators
NEC 250.34 Portable, Vehicle-Mounted, and Trailer-Mounted Generators
OSHA https://www.osha.gov/laws-regs/regul.../1926/1926.404

The most interesting and in depth site I found was Guy Holt's Local 481 GFCI Workshop - http://www.screenlightandgrip.com/ht..._Workshop.html
GFCI: Grounded Neutral Fault Detection Circuit.

Portable Generators - Half way down - (took me awhile to read that far)
Power Source Types: Floating Neutral generators, Bonded Neutral generators.

Systems Grounding and Equipment Grounding
Floating Neutrals vs. Bonded Neutrals, Floating Grounds vs Earth Grounds,

Portable Generators in Motion Picture Production - http://www.screenlightandgrip.com/ht...enerators.html

Older explanation of why <5kW portable generators don't have GFCI outlets
Portable Generators and OSHA Construction Regulations -
http://www.arrl.org/files/file/Techn...3-05%20(1).pdf

edit: Texas' electricity grid problems have me keenly interested in standby generators connections.

Very interesting read Gene.

A search on "System Grounding" and "Equipment Grounding" offers a great deal of information. I suppose if my Champion malfunctions and passes current to the chassis, an earth ground would prevent an issue. Since my unit housing is all plastic, I'll have to take a closer look to see if there are any metal parts that would be connected to the chassis. Bolts, Screws etc would most likely connect to the chassis.
To Teds point, if I cannot or do not touch the actual generator chassis, there would be no concern. If the chassis became hot and I touched it while standing on the ground, it looks like I could provide a path to an earth ground. Based on Champions advice and the information provided above, a ground lug along with Tucsons bonding plug would work with my EMS but I will need to use something shorter than 8ft of copper pipe. It would be easy to install a permanent earth ground on a private lot though.

Question: Would I disconnect the bonding plug if I want to use my generator to power through a transfer switch in my home during a power outage?

[Cate&Rob]

This discussion might be losing track of the purpose for a "ground" wire . . . or "safety ground" as it used to be called. Electric current is always trying to return to its source. The purpose of the safety ground is to provide a low resistance path back to the source from anything that becomes energized with electrical potential. The theory being that this low resistance path will safely flow enough current to open the fuse or the breaker on the feed side, stopping the flow off current. The intent is that the safety ground and the neutral only come together at the source of the electricity. (Thus the "bonding" plug often used with a portable generator)

The concept of using the earth as the ground path back to the source only works if everything associated with the wiring system also has the safety grounds attached to earth. This is not the case with an RV sitting on rubber tires with the landing gear sitting on plastic or wooden blocking. The RV is electrically isolated from the earth. The "ground" wire should go directly from the RV to the source of the electricity (the generator).

A GFCI compares the current flowing on the load side to the current flowing on the neutral side. If these are not exactly the same then the current is going somewhere else and the GFCI opens. A connection between neutral and ground somewhere other than at the source of the electricity can cause this . . . although, I will admit that I do not understand exactly why this is.

Rob

[gbkims]

Portable Generators and OSHA Construction Regulations - Rev 3-05 list three separate regulatory references.
1 Generator Grounding Electrode Exemption (system grounding)
2 Generator GFCI Exemption
3 Neutral Conductor Bonding Requirements for Generators

I'm not sure how these might apply to how portable inverter generators are used with RVs.


I think my Champion 4650W M# 200994 Inverter Generator operates as do nearly all the other inverter generators. (It's mostly going to be used at home.)

The generator's alternator AC output is rectified to DC, then DC is Inverted to 120VAC via the Inverter Module that has 2 ungrounded outputs for 120VAC..
Like shown at UNDERSTANDING PORTABLE INVERTER GENERATORS.

So they seem more like engine powered inverters vs. standard generators which output 120VAC directly from the generator's windings

The bonding plug that jumpers the ground to the neutral of the generator's outlets puts one of the Inverter's ungrounded H Bridge circuit outputs to chassis ground.
This works on most of the inverter generators. It does on my older Yamaha EF2400IS.
Since I haven't tried this with my new 200994 yet I'm wondering if bonding the Inverter's output is affecting its Current Sense circuit and tripping the Overload.

My 200994 front panel ground stud's GN-YL wire runs back to an engine ground point. I didn't pull apart the foam surrounding the back of the outlets to see how their grounds wire to the ground stud wire.
Another smaller GN-YL wire runs from an engine ground point to the front exterior of the inverter module.


How the inverters are designed seems to mostly off the shelf electronics.
https://www.ti.com/lit/pdf/slaa602 - 800VA Pure Sine Wave Inverter’s Reference Design
https://www.tntech.edu/engineering/p...i/Chapter2.pdf
https://www.edn.com/use-a-spwm-gener...-applications/
https://toshiba.semicon-storage.com/....jsp?did=61546

[KSC_Travels]

Hi all. Just for interest sake I came across this youtube channel a while back. Some good explanations on here about all things electricity. Can't vouch for its accuracy, but the explanations are well done (IMO).

[TedS]

Guest , you would remove the n-g bonding plug when you connect to power your house. The neutral is bonded to the ground in the house breaker panel.

[Guest]

Guest , you would remove the n-g bonding plug when you connect to power your house. The neutral is bonded to the ground in the house breaker panel.

Thanks Ted. One earth ground makes sense.

Jim

[TedS]

Hi all. Just for interest sake I came across this youtube channel a while back. Some good explanations on here about all things electricity. Can't vouch for its accuracy, but the explanations are well done (IMO).

That is a good video explanation for the why of ground and neutral connections. It's confusing when the battery example is used where the battery positive is connected to the socket base. Most US dc circuits would have the negative connected to the lamp base. Electron flow sense is opposite current flow sense in a circuit and that can be confusing , but that is historically true.