Inverter Prep Musings

[howson]

A recent post by donincanada59 has had me flummoxed. I think (maybe) I understand what's going on. Below is presented for your ridicule and scorn. (Kidding--but I would like feedback and your .02.)

The post referenced is here: https://gdrvowners.com/forum/operati...4153#post74153

Note that I'll post a PDF version in post 2 of this thread that is a duplicate of the embedded pictures (but the preferred format for some members).

If you quote this post, please trim out the pictures to shorten your reply/post.

---

---

---

---

After looking at this for an hour or so, the only reason I can see for the second 30A breaker is the output connection on the breaker is used as an input to pass 120vAC to the Microwave, General, and GFCI breakers.

Anyone disagree or have a different perspective?

Howard

[howson]

The attached PDF as noted in post 1 is attached.

[Country Campers]

That is the way I understand it. The power would go to the inverter, if it has a built in ATS, if not then it would go to the ATS then to the inverter. Either way it just passes the inverter when on shore power and only powers the 3 breakers to the right of the inverter "in" to the panel. I think that the pictures above explain this very well.

Brian

[ncitro]

That's what I picture as well. The second inverter breaker is really a main breaker for a small sub panel that's housed in the same enclosure. The jumper allows the circuits in the subpanel to receive shore power when there's no inverter installed. This install would only allow the inverter to power the subpanel, in order to feed the entire panel (as with a split phase Multiplus) you'd still need to pull the mains out to the Multiplus and leave that jumper in place.

[Jlawles2]

howson Howard, please bear with me a moment.

1 - Both the first picture of the full 10 breaker panel and the empty 10 breaker panel appear to be the same. (Main should be at the LEFT of picture 2)
2 - The breaker panel is wired A-B-A-B-A-B-A-B-B-B (note the 2 50A breakers). I can see this by looking at the lugs in the panel. It's apparent by looking at the top lugs that 1,3,5,and 7 are all on the same bar, while 2,4, and 6, are on the opposing bar, not clear is that 9 and 10 are also tied to 8 (hard to see the tie bar between 8 and 9 but clearly 9 and 10 lugs are on the same U shaped piece).
3 - by counting the lugs starting at the top of picture 1 and left of picture 2, the inverter prep is across lugs 7 and 8 (unless 8 is not part of 6 this will result in 240VAC) and lugs 9 and 10 appear to be on the same lug (B-B).

So this worries me a bit without seeing some additional details. Unless the inverter is using the opposing leg as the trip for supplying power, it appears the inverter is wired to feed from 24VAC.

Is there an inverter sub panel as this might clarify a few questions, or if there is a break in the bar between 7 and 8.

The breaker may be redundant, but it's the simplest way to make the connection the way the system is designed.

[ncitro]

I think it's wired for 120v to the inverter, there's a break in the bar between 7&8. 7 goes out to the inverter (or through the jumper) and back into 8 which is the main for the subpanel that feeds 9&10.

[howson]

Jlawles2 -- I had not considered the "A-B" setup, which makes sense based on the real world configuration (Mains are together at one end of the distribution box).

There is absolutely 120V going to the inverter (and being passed to the Refrigerator, General, and GFCI circuits) so while the drawings are not accurate showing that level of detail, the concept shown is still valid. The main point was to show (at least to my level of understanding) why GD used two 30A circuit breakers and labeled them "Inverter".

Thanks for the clarification on the Mains. I gotta remember about that A-B thing. That's the second time you've had to remind me about it!

[kengquist]

Jlawles2 -- I had not considered the "A-B" setup, which makes sense based on the real world configuration (Mains are together at one end of the distribution box).

There is absolutely 120V going to the inverter (and being passed to the Refrigerator, General, and GFCI circuits) so while the drawings are not accurate showing that level of detail, the concept shown is still valid. The main point was to show (at least to my level of understanding) why GD used two 30A circuit breakers and labeled them "Inverter".

Thanks for the clarification on the Mains. I gotta remember about that A-B thing. That's the second time you've had to remind me about it!

Reading your comment above, does your reference to the 120V going tot he inverter "and being passed to the refrigerator, general, and GFCI circuits" mean all of the outlets are hot when you have the inverter, even though there's no solar?

[howson]

kengquist -- first, noted that was your first post here on the forum. Assuming you're an owner of a Grand Design product, when you get a moment check out the Welcome Letter to New Members here: https://gdrvowners.com/forum/main-fo...to-new-members

Regarding your question, what must be understood is that solar can be (and in many times is) completely independent of an inverter circuit. The opposite is true, too. An RV can be equipped with an inverter and not have solar. How can there be an inverter without solar? An inverter uses power from the RV's batteries. How an RV's batteries are charged can be from a number of different sources. One of the ways to recharge batteries is solar, but solar is not required to use an inverter.

In the example circuit shown in this thread, when plugged into shore power the microwave, GFCI, and General circuits will have power. (I know..."duh"...sorry for stating the obvious!)

When shore power is offline, the inverter is powered on, and the RV's battery bank is connected to the inverter the Microwave, GFCI and General circuits are indeed "hot" as they are connected to the inverter's output. Overall power available, though, is limited to the inverter's capability (and how much juice is left in the battery bank).

I might have answered this question with more detail than desired...or maybe I missed the mark completely. Let me know either way if I cleared up any confusion (or added to it).

Howard

[kengquist]

kengquist -- first, noted that was your first post here on the forum. Assuming you're an owner of a Grand Design product, when you get a moment check out the Welcome Letter to New Members here: https://gdrvowners.com/forum/main-fo...to-new-members

Regarding your question, what must be understood is that solar can be (and in many times is) completely independent of an inverter circuit. The opposite is true, too. An RV can be equipped with an inverter and not have solar. How can there be an inverter without solar? An inverter uses power from the RV's batteries. How an RV's batteries batteries are charged can be from a number of different sources. One of the ways to recharge batteries is solar, but solar is not required to use an inverter.

In the example circuit shown in this thread, when plugged into shore power the microwave, GFCI, and General circuits will have power. (I know..."duh"...sorry for stating the obvious!)

When shore power is offline, the inverter is powered on, and the RV's battery bank is connected to the inverter the Microwave, GFCI and General circuits are indeed "hot" as they are connected to the inverter's output. Overall power available, though, is limited to the inverter's capability (and how much juice is left in the battery bank).

I might have answered this question with more detail than desired...or maybe I missed the mark completely. Let me know either way if I cleared up any confusion (or added to it).

Howard

Thank you so much. This is exactly as I had understood it to be, but someone is arguing with me that I'm not correct. I appreciate your confirmation and explanation.