IOTA Circuit breaker Box

You have a 20a breaker on the main panel for the inverter's output, but what is the circuit in the RV that the new breaker protects, and what is on that circuit? How does that circuit's wire (12AWG yellow supposed to be) also wire to that same new 20a breaker?

Would the breaker when off be able to stop inverter power from getting to that circuit? Not like a Main and a Branch?

Some folks use a sub- panel with circuits on it to run from the inverter. That way they can leave the converter, etc, on the main panel and not have that on the inverter.

The 120v wire from inverter output to the breaker has a ground wire (bare copper) in it. That ground wire should go to the RV frame, same as the 30a Main breaker's wire does. Neutral goes to the N buss, Hot to the breaker.

I have a 2000w PSW and a 300w MSW inverter. Both show two yellows (proper) with the three light tester in their 120v receptacles.

Went back quickly through posts and didn't find make and model of inverter.
Many inverters have a floating neutral. The instructions should show where to connect the ground to the neutral.

Well...I installed the inverter the other weekend and tested it after isolating it from shore power with a recepticle plug tester. It showed "open ground".
I must say that I have been relying on my friend for help who has experience installing a 3K inverter in his Motorhome and who has designed and installed 4 solar panel systems.
We must have overlooked something. The system on shore power with the inverter isolated tests OK and works just fine.
We did replace the single 20 amp breaker with a double 20 amp breaker. Originally it was marked 20 amp air conditioner. Now 1 is connected to the original A/C and the other is dedicated for the inverter.
Perhaps the inverter is not grounded properly? How would I check that out?
My family and I are actually staying in the rig now... so I might be able to go over it.
Any ideas or suggestions would be appreciated....thanks!

dougrainer wrote:
I asked about 50 or 30 amp service because you CANNOT add excess amp draw to a 30 amp box. 30 amp RV boxes are designed for the 30 amp load in the RV and are designed to split the loads to total 30 amp. If you are trying to run an extra 20 amp circuit and appliance you will overload and trip the Main 30 amp breaker in the Breaker box or the CG pedestal pole breaker. Not really dangerous as the breakers will do their job but just an annoyance. Doug

30A boxes are already overloaded. Try running a/c, water heater, refrigerator, lights and one good plug load at the same time.

A bigger issue to note about adding circuits is the NEC only allows five branch circuits from a 30A panel. This note only applies if you actually care what the NEC says.

You should not backfeed the 120 volt system from an inverter!
This does not have any safeguards to prevent backfeeding into the power suppliers system.

DIVE2XS wrote:
The 2nd 20 amp breaker is only used when I have isolated the shore power from the system to use the inverter. I just wanted to be able to use it during short periods such as staying overnight enroute to another location so I don't have to fire up the generator to support the medical devices and such for the night.

You don't need any more circuit breakers to do that. All you do is plug the shore cable into the inverter and shut off the converter. (with the fridge and WH on gas to reduce 120v load)

It is possible that you are trying to say that you want to put the converter on its own circuit breaker so it can be a switch to turn the converter on and off. That is if the converter now shares its breaker with the receptacles.

EDIT--Iota converters are mostly(all?) the plug in type, so just unplug it to turn it off.

Also most converters only need 15a breakers on 14 wire. Higher amp, non-PF corrected converters such as the PD 80 ampers do require 20a breakers and 12 wire.

To add to the confusion, I know my 2003 Komfort 5er (built in Oregon) had a "USA" and a "Canadian" version. The USA version had all "20a" breakers, while the Canadian version was all 15a except the one for the air conditioner. I don't know if the USA version really had 12 wire to all its receptacles and if those had the 20/15 plug ins. Mine had 14 wire to 15a CBs and receptacles.

DIVE2XS wrote:
The 2nd 20 amp breaker is only used when I have isolated the shore power from the system to use the inverter. I just wanted to be able to use it during short periods such as staying overnight enroute to another location so I don't have to fire up the generator to support the medical devices and such for the night.

Consider a small $50 transfer switch in the existing branch circuit. This provides automatic isolation. Allows you to use the existing outlets. Can provide backup power automatically if the utility power goes out.

https://www.donrowe.com/KISAE-TS15A-Automatic-Transfer-Switch-p/ts15a.htm

The 2nd 20 amp breaker is only used when I have isolated the shore power from the system to use the inverter. I just wanted to be able to use it during short periods such as staying overnight enroute to another location so I don't have to fire up the generator to support the medical devices and such for the night.

dougrainer wrote:
I asked about 50 or 30 amp service because you CANNOT add excess amp draw to a 30 amp box. 30 amp RV boxes are designed for the 30 amp load in the RV and are designed to split the loads to total 30 amp. If you are trying to run an extra 20 amp circuit and appliance you will overload and trip the Main 30 amp breaker in the Breaker box or the CG pedestal pole breaker. Not really dangerous as the breakers will do their job but just an annoyance. Doug

I believe NEC allows max 5 branch circuits with a 30 amp main. The breaker ratings and appliances in a 30 amp RV very typically can exceed 30 amp draw. Manual power management is needed or the lights go out.

Regardless of NEC I added 2 more breakers but they are for items very rarely used. Never an issue.

dougrainer wrote:
I asked about 50 or 30 amp service because you CANNOT add excess amp draw to a 30 amp box. 30 amp RV boxes are designed for the 30 amp load in the RV and are designed to split the loads to total 30 amp. If you are trying to run an extra 20 amp circuit and appliance you will overload and trip the Main 30 amp breaker in the Breaker box or the CG pedestal pole breaker. Not really dangerous as the breakers will do their job but just an annoyance. Doug

You still have the option of "power management" to not overload.

There is also the confusion where USA posters often say "20a" when talking about 15a. The key is whether the "20a" really has 12 wire instead of 14 wire to it.

Not sure the OP has a clue about all that.