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We have the NEC code for residential electrical, ABYC standards for marine electrical, is there an equivalent for mobile/vehicle/rv electrical?

So in a sense, the chassis of an isolated (from earth) vehicle electrical system, is functionally equivalent to earth ground in building electrical systems.
That statement is broad sweeping. Functionally equivalent is difficult to understand unless you completely understand the function of earth ground in building systems.
 
That statement is broad sweeping. Functionally equivalent is difficult to understand unless you completely understand the function of earth ground in building systems.

You're right. Probably not the best term to use. How about "conceptually similar"
 
One reason I am interested in RV Electrical System grounding is because of my exposure to Inverter System grounding recently.
I installed an MHS1230 inverter in my camper. The Magnum Owners Manual provided details for proper grounding of the Campers Electrical System. Here's the text and figure given:

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In addition, here are the definitions of terms used:

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One reason I am interested in RV Electrical System grounding is because of my exposure to Inverter System grounding recently.
I installed an MHS1230 inverter in my camper. The Magnum Owners Manual provided details for proper grounding of the Campers Electrical System. Here's the text and figure given:

View attachment 10558

In addition, here are the definitions of terms used:

(having image problems, will reboot and try again)

This is really good info, thanks! I've read similar advice in the Samlex manual but this is more clear. I think that so far, my design has followed these practices (though the only equipment I've explicitly equipment grounded/bonded is the inverter chassis and the PV frame as these are the only components that explicitly mention grounding in their manuals. The only other difference I see is that my DC ground busbar is connected to the negative busbar not directly to the battery negative
 
This is really good info, thanks! I've read similar advice in the Samlex manual but this is more clear.
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Yes, Magnum Energy has their stuff together. excellent install/operation info in their manuals.
 
There is another challenge for pass thru smart inverters. The System Bonding Jumper (SBJ). The one and only one point in an electrical system where the ac system Neutral and Ground wires are bonded together. Here's the info:

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I can't really read the text of this last post, But from what I can see from the diagrams, this might be similar to this section of the Samlex Evo manual:

3.14.1 OUTPUT NEUTRAL TO CHASSIS GROUND BOND SWITCHING

As required by NEC and UL specification 458, AUTOMATIC Output Neutral to Chassis Ground bond switching arrangement has been provided in these units through “Output Neutral to Chassis Ground Bond Switching Relay” [K4 in Figs 4.1(a) and 4.1(b)] to switch bonding of the Output Neutral Connector of the Inverter Charger as follows:

• When operating as an inverter, the current carrying conductor of the Inverter Section that is connected to the Output Neutral connector of the Inverter Charger is bonded to the metal chassis of the inverter by the “Output Neutral to Chassis Ground Bond Switching Relay” [K4 in Figs 4.1(a) and 4.1(b)]. As the metal chassis of the inverter is in turn bonded to the RV Ground (chassis of the RV) or to the Boat Ground (DC Negative Grounding Bus Bar and the Main AC Grounding Bus Bar are tied together in a boat and this is called the “Boat Ground”), this current carrying conductor of the Inverter Section will become the Grounded Conductor (GC) or the Neutral of the Inverter Section.

• When in Charging Mode, the Neutral conductor of the Grid power/Generator will be connected to the Output Neutral connector of the Inverter Charger. At the same time, the “Output Neutral to Chassis Ground Bond Switching Relay” [K4 in Figs 4.1(a) and 4.1(b)] will unbond (disconnect) the Output Neutral connector of the Inverter Charger from the chassis of the Inverter Charger. This will ensure that the Grounded Conductor (GC) / Neutral of the Grid power/Generator is bonded to the Earth Ground at one single point at the location of the AC Power Distribution System of the Marina/RV Park.

• Disabling Neutral to Ground Bond: In some applications, the Output Neutral may be required to remain isolated from the chassis/Ground at all times. For this, automatic Ouput Neutral to Chassis Ground bond can be disabled by disconnecting the Male/Female Quick Disconnect located in the AC wiring compartment. [Please see (i) 13, Fig 3.9 and (ii) "QD" in Figs 4.1(a) and 4.1(b)].
 
The portable generator challenge, when used to provide shore power to a RV electrical system.
Note that a portable generator is most likely not UL listed for use in an RV.......
The challenge is that some portable generators do not have a System Bonding Jumper (SBJ) connecting the Neutral wire to the ground wire at the source, the generator. This is the case with the Honda EU Inverter 2000i portable generator.
I searched for an answer years ago when I bought the generator and found this:

 
So in a sense, the chassis of an isolated (from earth) vehicle electrical system, is functionally equivalent to earth ground in building electrical systems.
Hmmm, I‘m certain that I’ve been reading that, for connecting to shore power at least, chassis does get connected to shore ground. I’ve also read that neutral absolutely does not get bonded to ground in/on the RV.

edit: yeah...page 2 of the comments shows you are aware. ?
 
...........I’ve also read that neutral absolutely does not get bonded to ground in/on the RV.
.........
Absolutely is an all inclusive statement.
-If an RV is on shore power supply, the Neutral-Ground bond is provided at the shore power source and ground is provided from the shore power source. The RV chassis is bonded to the ground buss at the RV 120v/240v panel. Neutral and ground are isolated in the RV.
-If the RV is on its on board generator power supply, the Neutral-Ground bond is provided at the generator and ground is provided at the generator power source (generator chassis bonded to rv chassis). The RV chassis is bonded to the ground buss at the RV 120v/240v panel. Neutral and ground are isolated in the RV.
-If the RV is on its inverter power supply, the Neutral-Ground bond is provided at the inverter and ground is provided at the inverter power source (inverter chassis bonded to rv chassis). The RV chassis is bonded to the ground buss at the RV 120v/240v panel. Neutral and ground are isolated in the RV.
 
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Where did you read that?
Disclaimer, for anyone looking for concrete consultation or advice from an electrician, DO NOT TAKE THESE STATEMENTS AS GOLDEN. I am NOT an electrician.

I do not remember, now, but it appears some of the data linked here also supports that. Neutral to ground bond is to be handled by shore. As it applies to generators, I do not remember fully remember now, but I think you are supposed to know if the genset has neutral bonded to its chassis, and if so, that bond is supposed to be disabled. One more detail that changes (or effects) the way this wiring is supposed to happen is if your shore power receptacle (I think the one that lives on the RV) is a GFCI outlet or not. I do not recall the details of this now, but I know enough to know these are areas to be extremely aware of and cautious about when performing the install. You can bet when it comes down to actually doing this wiring, I will be following codes and instructions line by line while checking and double-checking the work I’ll be doing. I will also know that the sources I use to guide me will be checked and double-checked as authoritative. I do not wish to be a hazard to myself or someone else.
 
Absolutely is an all inclusive statement.
-If an RV is on shore power supply, the Neutral-Ground bond is provided at the shore power source and ground is provided from the shore power source. The RV chassis is bonded to the ground buss at the RV 120v/240v panel. Neutral and ground are isolated in the RV.
-If the RV is on its on board generator power supply, the Neutral-Ground bond is provided at the generator and ground is provided at the generator power source (generator chassis bonded to rv chassis). The RV chassis is bonded to the ground buss at the RV 120v/240v panel. Neutral and ground are isolated in the RV.
-If the RV is on its inverter power supply, the Neutral-Ground bond is provided at the inverter and ground is provided at the inverter power source (inverter chassis bonded to rv chassis). The RV chassis is bonded to the ground buss at the RV 120v/240v panel. Neutral and ground are isolated in the RV.
You’re right. My apologies for wording it the way I did, and am absolutely happy to defer to someone authoritative on the matter. That said, if I start seeing discussion that I think looks dangerous, (expert or not) I am going to chime in, at the very least to get whomever to hopefully rethink and/or double check to make sure they know what they’re doing.
 
Hmmm, I‘m certain that I’ve been reading that, for connecting to shore power at least, chassis does get connected to shore ground.
The important distinction here is the part in bold: "the chassis of an isolated (from earth) vehicle electrical system," when I talk about a vehicle Isolated from earth ground, I'm talking about a vehicle without shorepower (or not plugged into shorepower)
I’ve also read that neutral does not get bonded to ground in/on the RV.
This statement applies when connected to shorepower.
Or possibly a more correct way to think of it is: Neutral should be bonded to ground in 1 place only.
Since neutral and ground are bonded on the shore side of a shorepower connection, any onboard neutral ground bonds would need to be disconnected when shorepower is connected, but when not using shorepower, an onboard neutral ground bond would be used. An inverter/charger meant for mobile/marine installs often handles this for you (look for UL 458)

As to generators, I find them to be confusing and I have never used one (or planned to) so my knowledge is less than limited.

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In part due to my prodding (sorry :rolleyes:), @filtgerguy took the lead on the substantial task of writing a series of primers on grounding (they build on each other, part 4 is mobile specifc). I highly suggest checking them out if you have a chance. @RandyP I /We would value your input on the mobile section if you have any. You are more familiar with the RVIA/LV than most here, I don't know how well that covers grounding, but neither of us had a copy to reference. So if there are relevant tidbits, it would be good to know.
 
Wondering, are there any requirments to post a notice somewhere visible if you have propane tanks or a gas generator on board your RV?
 
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