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Inverter ground

When not plugged in to shore power, and operating on the inverter does the 120v ground do anything? I'm not the brightest but I don't see how it can do anything it's not grounded
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Inverter ground

Reply #1 –
Bruce,
There are a lot of electrical geniuses on this forum ( I for sure, am not one). But let me take a guess. The ground in the inverter system is similar to the ground wire on your car. While not going to actual "Ground", it is the electrical mechanism to complete the circuit so that the electrical power can flow.

It'll be interesting to see how close I am on this.

Len
Len and Deb Speiser
1999 U270 36'
2017 Jeep Wrangler Unlimited
You're either on the bus, or you're off the bus!--Ken Kesey
If you're lucky enough to live in a bus, you're lucky enough!

Re: Inverter ground

Reply #2 –
Quote from: bbeane –
When not plugged in to shore power, and operating on the inverter does the 120v ground do anything? I'm not the brightest but I don't see how it can do anything it's not grounded
Without looking at your electrical schematics....... I will take a stab at explaining this. First I am not sure which 120v ground you are referring to, or what exact ground point is not connected.
Per code a residential 120/240 volt power source should have the neutral and grounding conductor bonded together as close as possible to the voltage source. I would think this should apply to an inverter also as it is the 120v power source. The Neutral or "grounded conductor" is a normal current carrying conductor and the "ground" or "grounding conductor" normally a bare or green colored conductor is there to facilitate the operation of the ground fault or short circuit device. Current is only present on the "ground" in a fault condition.
If it is not connected at the power source? then you are correct, it wont do what it is supposed to do. It must provide a fault path back to its source.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Inverter ground

Reply #3 –
Len, I realize what you are saying, however the inverter on the 120v side is not grounded to anything. Unlike a shore power that is " supposed" to be connected to a ground rod. I wouldn't think that the 12v and 120v grounds would be integrated in the inverter. In the event of a short on the 120v side the 12v side is not going to be happy.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Inverter ground

Reply #4 –
120 VAC in your RV
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Inverter ground

Reply #5 –
It would be nice if the RV parks had a ground rod by the water hook up. We could attach a ground cable to it when we hookup. We could push our own ground rod in but I would probably find one of the utilities. Our own ground rod might be good when boondocking. Maybe that would help if you had a problem like a hot skin on your coach?
I know this would be redundant to the ground in the park hookup but so easy to do and would add another layer of protection.
John Duld
1995 U320C SE 40'

Re: Inverter ground

Reply #6 –
I went through this last winter, when I discovered my surge protector showing "no ground" when plugged my little 300 watt inverter for the front video system.
I read several places this is normal, and to NOT hook the ground to anything, or it will "let the smoke out of the inverter". I believe on my inverter, they just installed a ground lug port, for the accessory plugged into it.
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: Inverter ground

Reply #7 –
The ground side of the landline 120 volt wiring is not connected to the neutral side like it is in your house.  Ground it is connected to the frame of the coach with a big green wire at the main circuit panel.

It is important to know what you are plugging into at the post.  Miswired posts are common and can do damage to things in your coach or worse, to you when you plug in.

Your inverter (or converter or charger or solar charger) should have a ground lug on it that should be connected with appropriate sized wire to a solid metal point that shows continuity to the 120 volt ground.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Inverter ground

Reply #8 –
Quote from: Roger & Susan in Home2 –
The ground side of the 120 volt wiring is not connected to the neutral side like it is in your house.  Ground it is connected to the frame of the coach with a big green wire at the main circuit panel.

Correct...... the neutral and ground should be separated in the coach wiring as it is in the coach power cord. Theses two should only be bonded at the closest point to the power source. Usually the utility meter can or the Main panel of your house.

It is important to know what younare plugging into at the post.  Miswired posts are common and can do damage to things in your coach or worse, to you when you plug in.

Your inverter (or converter or charger or solar charger) should have a ground lug on it that should be connected with appropriate sized wire to a solid metal point that shows continuity to the 120 volt ground.

The chassis should be connected to the power cord grounding conductor along with all of the 12volt grounds.

Incorrectly wired campground pedestals are NOT uncommon...... unfortunately.

 
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: Inverter ground

Reply #9 –
Quote from: FourTravelers –
Per code a residential 120/240 volt power source should have the neutral and grounding conductor bonded together as close as possible to the voltage source. I would think this should apply to an inverter also as it is the 120v power source.
The AIMS inverter I installed in our '91 bonded ground to neutral when providing inverter power to the inverter powered outlets, and unbonded ground and neutral when passing shore power through to the inverter powered outlets. The manual states this meets code requirements.
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Inverter ground

Reply #10 –
Quote from: prfleming –
The AIMS inverter I installed in our '91 bonded ground to neutral when providing inverter power to the inverter powered outlets, and unbonded ground and neutral when passing shore power through to the inverter powered outlets.

This is the common way, always read the installations instructions for YOUR inverter to verify that is how yours should be wired.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Inverter ground

Reply #11 –
AIMS also recommended using 8 gauge or greater wire to ground the inverter chassis to the coach chassis, I used 4 gauge, as I had some of that available.
Peter and Tammy Fleming
1991 U300 GV 40 - Sold, owned for 4 years
Downsized to Roadtrek Popular 210 class B

Re: Inverter ground

Reply #12 –
Here is what Victron says for the MultiPlus...

"The MultiPlus is a safety class I product (supplied with a ground terminal for safety purposes). Its AC input and/or output terminals and/or grounding point on the outside of the product must be provided with an uninterruptible grounding point for safety purposes.  The MultiPlus is provided with a ground relay ... that automatically connects the Neutral output to the chassis if no external AC supply is available. If an external AC supply is provided, the ground relay H will open before the input safety relay closes. This ensures the correct operation of an earth leakage circuit breaker that is connected to the output.

─ In a mobile installation (for example, with a shore current plug), interrupting the shore connection will simultaneously disconnect the grounding connection. In that case, the casing must be connected to the chassis of the vehicle"

Be sure to connect the Multiplus case to a coach chassis ground.  I used a 6 ga green sheathed wire.


Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN
 

Re: Inverter ground

Reply #13 –
Quote from: prfleming –
The AIMS inverter I installed in our '91 bonded ground to neutral when providing inverter power to the inverter powered outlets, and unbonded ground and neutral when passing shore power through to the inverter powered outlets. The manual states this meets code requirements.

It should meet codes requirement, bonding the ground to neutral when supplying power to its connected outlets and providing isolation when passing shore power to outlets.

good to know and thanks for sharing....... would like to know if all inverter manufacturers are required to meet this same design?
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota