Adding a 2000W Renogy Inverter to my Truck Camper

[CampingLife]

Hi All,

I am looking at adding a 2000W Renogy inverter to my truck camper. My current plan is to add this as an AC source, so it'll go straight to the distribution panel in the camper as if it was shore power or a generator, from there it'll run the ac circuit in the camper as it pulls from the 12v lithium battery. I also have solar and a dc-dc charger connected to my truck. I'm assuming the 7-pin truck connector's gorund cable is for the running/break lights on the camper and those are on a different circuit. I'm not sure how the aux-charging in the 7-pin connector impacts my system.

My primary concern is getting the "ground" correct for the system with an inverter added. My understanding is that the panel in the camper is considered a "sub-panel" and neutral and ground are not bonded. When you plug your camper into a generator, that generator bonds neutral with ground so if there is a fault, breakers or fuses blow so you don't get a zap when you touch a charged item. Alternatively, if you plug into shore power, you utilize shore power's ground. Now, with the inverter acting as my "shore power", I think the neutral needs to be bonded with the ground. Reading through the renogy manual, it explicitly states that the wired AC output has neutral bonded to ground within the inverter, so I should be good to essentially wire my inverter into the camper's distribution panel. Additionally, I"ll need to route the Inverter's chassis ground to the distribution panel's ground bus bar in case there is a fault and the inverter case becomes charged. Additionally, I"ll need to ensure that the converter is disable when the inverter is on and I'm guessing the inverter needs to be off if shore power is actually plugged in...but I"m not sure on this. Really appreciate any feedback. I have diagramed out the major components below:



Thank you!

 

[Bobert]

I'm assuming the 7-pin truck connector's gorund cable is for the running/break lights on the camper and those are on a different circuit. I'm not sure how the aux-charging in the 7-pin connector impacts my system.

You have 3 or 4 electrical systems on your rv. One is the driving lights and although the positive side of the supply for the running lights is totally separate from the other systems in the rv the ground interconnects between all the systems in the rv as a ground wire connects to the frame of the rv from the 7 pin connector. If you have a separate brake-away battery you could argue that the brakes are also a separate electrical system, also grounded to the frame. Your house battery system is also grounded to the frame of the trailer and so is the ground side of the ac system in the camper. So technically the 7 pin is a separate circuit but the ground is common to each system.

Most I have heard of doing this type of thing simply wire a 30amp plug onto the inverter and plug the shore power cord into that and that way they never accidentally connect shore power to the inverter or accidentally create a double neutral ground bond. It’s a pretty economical solution.
A manual transfer switch can also do this as long as it has enough connections to insure the breaking of the neutral ground bond when the inverter is bypassed in favor of shore power. The advantage of the transfer switch is that the larger ones could also switch the converter at the same time.

Make sure your you’re rig is safe if someone else hooks it up. Be sure it is impossible for someone to make the shore power cord “live” if the inverter is on, make a double neutral ground bond. The inverter converter loop issue is less dangerous but It would be better if that was foolproof too.

 

[CampingLife]

You have 3 or 4 electrical systems on your rv. One is the driving lights and although the positive side of the supply for the running lights is totally separate from the other systems in the rv the ground interconnects between all the systems in the rv as a ground wire connects to the frame of the rv from the 7 pin connector. If you have a separate brake-away battery you could argue that the brakes are also a separate electrical system, also grounded to the frame. Your house battery system is also grounded to the frame of the trailer and so is the ground side of the ac system in the camper. So technically the 7 pin is a separate circuit but the ground is common to each system.

Thank you! This is starting to make sense, everything sharing a common ground. Its a truck camper not a trailer but I suspect the

Most I have heard of doing this type of thing simply wire a 30amp plug onto the inverter and plug the shore power cord into that and that way they never accidentally connect shore power to the inverter or accidentally create a double neutral ground bond. It’s a pretty economical solution.
A manual transfer switch can also do this as long as it has enough connections to insure the breaking of the neutral ground bond when the inverter is bypassed in favor of shore power. The advantage of the transfer switch is that the larger ones could also switch the converter at the same time.

I really like this idea. I was looking at transfer switches but the reality is that I've plugged into shore power maybe 3 times in the last 3 years. This will be cheaper and allow me to maintain the ability to plugin to shore power. I assume that I will still need to run a wire from the inverter case's ground to the panel's ground in addition to plugging in the shore power cord. Any concerns with that wire being connected while the inverter is unplugged/off? It simply becomes part of the frame that is grounded at that point correct?

Make sure your you’re rig is safe if someone else hooks it up. Be sure it is impossible for someone to make the shore power cord “live” if the inverter is on, make a double neutral ground bond. The inverter converter loop issue is less dangerous but It would be better if that was foolproof too.

I think I will simply disconnect the converter to avoid this situation. Just to confirm, it is correct that the inverter forms the neutral-ground bond when it feeding the panel with AC?

Really appreciate the feedback.

 

[dcg9381]

I think I will simply disconnect the converter to avoid this situation. Just to confirm, it is correct that the inverter forms the neutral-ground bond when it feeding the panel with AC?

Really appreciate the feedback.

I've got a truck camper also, but this HAS to be a common problem with RVs. You may get better answers on an RV forum if you refer to the inverter as a "generator". I believe you are right that the inverter needs to bond N/G when on inverter power. I believe that the "converter" is the piece you're missing as it is what switches power sources. I don't see it in your picture. I ASSUME that it also switches away from the inverter N/G bond when you tie to shore power, but have not implemented one to know that this is the case.

 

[CampingLife]

That's exactly how I'm viewing it, as a generator. I don't know what I don't know though so I want to make sure to call it what it is in case there is an unknown.

 

[dcg9381]

I think I told you wrong. Converter is shore power to 12V battery charge. Apparently RVs have a "transfer switch". Bet good money the bonding is switched here. If you're running an inverter, you may want a "manual" transfer switch over the automatic type that comes with most generator equipped RVs.

 

[Bobert]

I think I will simply disconnect the converter to avoid this situation. Just to confirm, it is correct that the inverter forms the neutral-ground bond when it feeding the panel with AC?

That is going to depend on the inverter but you can test the inverter to see if has a neutral ground bond.

 

[CampingLife]

Thanks Bobert, the manual confirmed that inverter bonds neutral to ground.