Confirm use of AC distribution box after multiplus

[demongman7]

For some reason I have really been struggling to find an appropriate pre-made solution for my AC distribution panel after my multiplus 3000W. To my knowledge, I should have a 50A main breaker w/ reverse polarity because the multiplus can pull from both shore / batteries for a combined 50A. However, I'm having a lot of trouble finding an AC distribution panel with a 50A breaker already installed. Even the blue sea panels are typically 30A breaker. Therefore, I'm hoping someone may validate that my plan for an AC distribution panel is not dangerous or crazy.

I purchased a Paneltronics Standard AC 6 position breaker panel, and a Paneltronics 50A w/ reverse polarity breaker. I plan to replace the pre-installed 30A breaker with the new 50A breaker. Does anyone see a reason why I shouldn't (or can't) do this? I haven't been able to confirm what the max capacity of the panel is, but I expect it should be well above 75A given the breakers that come pre-installed, and considering the fact that there are empty positions. I called paneltronics several times with no answer. Am I missing something obvious? I see on Explorist life's website he hacks together his own distribution box, and Faroutride quotes a blue sea 50A panel that I can't find, but what are other people doing for this situation with a 3k multiplus?

I've included a picture of this part of my wiring diagram - I have a 30A shore power inlet, multiplus 3k, and this distribution panel will lead to 4x 20A GFCI outlets, one of which powers a water heater. I know the Paneltronics panel comes with 15A and 10A breakers pre-installed, so they will technically be undersized for my outlets - but as long as this isn't a huge problem, I'll just position it so the 10A breaker is used for an outlet that I don't expect to see large loads.

 

[Hedges]

I'm not sure any "main" breaker is required on the output feeding breaker panel.

The manual mentions GFCI ("earth leakage") breaker. It also says 75A, for 25A from inverter + 50A

"AC-out-1 (see appendix A)The AC output cable can be connected directly to the terminal block "AC-out".From left to right: “PE” (earth), “N” (neutral) and “L” (phase).With its PowerAssist feature the Multi can add up to 3kVA (that is 3000 / 120 = 25A) to the output during periods of peak power requirement. Together with a maximum input current of 50A this means that the output can supply up to 50 + 25 = 75A.An earth leakage circuit breaker and a fuse or circuit breaker rated to support the expected load must be included in series with the output, and cable cross-section must be sized accordingly. The maximum rating of the fuse or circuit breaker is 75A."

https://www.victronenergy.com/upload/documents/Manual-MultiPlus-3k-120V-(firmware-xxxx4xx)-EN.pdf

The particular breaker you're looking at has 3 poles, to disconnect from neutral of shore power and to detect reverse of Line and Neutral, causing it to disconnect. Your application single phase 120V. A 1-pole breaker on output of inverter would shut off feed to panel.

Same breaker listed elsewhere:

Paneltronics Breaker 50 Amps w/Reverse Polarity Trip Coil - White

Shore Main Circuit Breaker with Reverse Polarity Trip Coil, 50 Amps, White Amperage: 50 Amps Shore main AC circuit breaker for Paneltronics electrical distribu

www.wholesalemarine.com

Does the panel you bought come with a 3-pole 30A breaker?
Does it have a busbar to distribute its output to the other breakers? That would be sized for some maximum current.

 

[demongman7]

I'm not sure any "main" breaker is required on the output feeding breaker panel.

The manual mentions GFCI ("earth leakage") breaker. It also says 75A, for 25A from inverter + 50A

"AC-out-1 (see appendix A)The AC output cable can be connected directly to the terminal block "AC-out".From left to right: “PE” (earth), “N” (neutral) and “L” (phase).With its PowerAssist feature the Multi can add up to 3kVA (that is 3000 / 120 = 25A) to the output during periods of peak power requirement. Together with a maximum input current of 50A this means that the output can supply up to 50 + 25 = 75A.An earth leakage circuit breaker and a fuse or circuit breaker rated to support the expected load must be included in series with the output, and cable cross-section must be sized accordingly. The maximum rating of the fuse or circuit breaker is 75A."

https://www.victronenergy.com/upload/documents/Manual-MultiPlus-3k-120V-(firmware-xxxx4xx)-EN.pdf

The particular breaker you're looking at has 3 poles, to disconnect from neutral of shore power and to detect reverse of Line and Neutral, causing it to disconnect. Your application single phase 120V. A 1-pole breaker on output of inverter would shut off feed to panel.

Same breaker listed elsewhere:

Paneltronics Breaker 50 Amps w/Reverse Polarity Trip Coil - White

Shore Main Circuit Breaker with Reverse Polarity Trip Coil, 50 Amps, White Amperage: 50 Amps Shore main AC circuit breaker for Paneltronics electrical distribu

www.wholesalemarine.com

Does the panel you bought come with a 3-pole 30A breaker?
Does it have a busbar to distribute its output to the other breakers? That would be sized for some maximum current.

Thanks for the response! I appreciate you pointing out the manual's comments on max output with PowerAssist - in this case if the output could reach 75A, it seems that I would want a 75A breaker instead of 50A? (Although I can't imagine a scenario where I require 75A all at once). Strangely, all of the guides for van builds that I've seen have only ever suggested a 50A main breaker, but I haven't seen one that uses a 75A after the inverter.

With regard to your two questions, I guess this is what I'm having trouble confirming. I have not received the panel yet, but suspect it does come with a 3-pole 30A breaker based on the information included here on a different website. I think it would have to have a busbar included to distribute output to the other breakers, but am not sure what it is sized for or how to confirm. I'll continue to try and call Paneltronics.

Is there a better solution that anyone would recommend for what I'm trying to do? I'm fine buying anything at this point, just seems like there isn't a perfect, simple solution that I've found.

 

[demongman7]

Thanks for the response! I appreciate you pointing out the manual's comments on max output with PowerAssist - in this case if the output could reach 75A, it seems that I would want a 75A breaker instead of 50A? (Although I can't imagine a scenario where I require 75A all at once). Strangely, all of the guides for van builds that I've seen have only ever suggested a 50A main breaker, but I haven't seen one that uses a 75A after the inverter.

With regard to your two questions, I guess this is what I'm having trouble confirming. I have not received the panel yet, but suspect it does come with a 3-pole 30A breaker based on the information included here on a different website. I think it would have to have a busbar included to distribute output to the other breakers, but am not sure what it is sized for or how to confirm. I'll continue to try and call Paneltronics.

Is there a better solution that anyone would recommend for what I'm trying to do? I'm fine buying anything at this point, just seems like there isn't a perfect, simple solution that I've found.

Separately, if the maximum output of the Multiplus is truly 75A, maybe I would be better off using a 50A breaker, but somehow program the multiplus to limit output to 50A rather than 75A?

 

[Q-Dog]

Do you really need a "main" breaker? What is the scenario that would trip a 50 amp or 75 amp breaker without tripping an individual circuit breaker or overloading the inverter?

 

[demongman7]

Ok - I got a bit more information from Paneltronics - they say the 50A breaker I selected will work as a replacement for the default 30A breaker in the panel. So now it's just a question if this setup makes sense with my 3K Multiplus.

To your questions - they said the included breaker is not a traditional 'three-pole', rather it's a 2 pole with a special pole for reverse polarity (one pole would be 65VAC wheras a traditional 3 pole would have the same V across all three). In the linked diagram, to replace, normally I'd remove the surge arrestor and reattach to the new 50A breaker. However, paneltronics said because this is going to be hard wired for an inverter, there is no chance for reverse polarity, and a dual pole breaker would be sufficient. If I keep this panel, I don't need to reconnect the surge arrestor in my case.

Also the included bus bars are rated to 100A.

So effectively, it seems possible to swap the 50A breaker into the panel but I'm back to square 1 to determine whether this makes sense for 3K Multiplus considering the comments surrounding 75A maximum output per @Hedges That said, my shore inlet is limited to 30A, so in my view 30A + 25A from PowerAssist = 55A max potential. So a 50A breaker would not be too far off.

 

[demongman7]

Do you really need a "main" breaker? What is the scenario that would trip a 50 amp or 75 amp breaker without tripping an individual circuit breaker or overloading the inverter?

Honestly I don't know - I agree with you that I think I'd trip an individual breaker (either at outlet or on the panel) long before I hit 50A on the main, but nearly every van electrical wiring diagram I see has a 50A main reverse polarity breaker after the inverter so I feel like there must be a reason. This also confuses me when considering the feedback from the Paneltronics rep who said in a hardwired application there is no chance for reverse polarity - so why all the reverse polarity breakers in van wiring diagrams?