Yes on the Midnight SPDs.
We are on a new page ... so thank you again for your patience and detailed explanations. I've reread the thread at least 10 times. No telling what I haven't yet absorbed though. ;)
Added interlock breaker.
> Don't want to get distracted with this right now. But, once I have the base design I'm considering adding the Midnight Solar AC Panel which provides a 60amp bypass from the PV input to the main panel if SI is down. I suppose the interlocked breaker backfeed from...
Focusing on the breakers, I simplified the diagram per this post and another that referenced the 70A main breaker.
70A in the main panel to SIs
56A in the PV landing panel to/from SI.
32A breaker (25A max output) for each SB 6.0 ... will change if I go with the 7.7 (40A breaker for 32A max...
@Hedges, I'm confused about 3 strings; i.e. 3 MPPT. Seems to me I get to maximum wattage with only 2 strings, so really unsure how or why 3 strings would be leveraged. Unless we are thinking 2 of the strings are at 90' different orientation so only 2 highly active at any one time.
The...
yes, @Hedges and I discussed. I subsequently saw this (see JPG) from: that helps further clarify. Basically, if grid-tied should have 1W SB for 1W of Sunny Island.
I wasn't clear above, the sizing was for the AC-1 (island) side so I'm going for 1:1 on wattage.
so, with 2 SI, I will have 2...
@Hedges @MurphyGuy String sizing validation.
Sunny Boy 6.0 - 3 MPPT - 10a/mppt - 100-550V operating voltage - 600V max
Not committed to this, just using it as an exercise: JA Solar 410 W 40.87 VOC
18x ~410W 41 V
9s x 2 - I didn't write 2p here because each string will go into a separate MPPT...
Agree with your point on price. What if I said I was going to buy the equipment right away, but still was going to approach the build incrementally? Thoughts on that as an approach?
@Hedges @MurphyGuy - When I lead software development projects I'm very good at breaking down a project into achievable units and iterating so that we can both show traction and successes as well as reduce risk to a big bang deliverable.
Therefore, my inclination is to do the same with this...
I cannot find where you get 12kw SI (2x6048) can manage 24kW SB.
Here's the Sunny Island datasheet.
https://files.sma.de/downloads/SI6048US-DS-en-28.pdf?_ga=2.6202801.344650644.1647641451-782371609.1647173240
@Hedges - Really embarrassing question, but if I have 2 Square D 40MW225 panels with 200 amp main breaker, does that mean I have 400 amps coming into the house?
The one panel does not feed the other. They both come from the meter.
ah, might not know what I'm talking about....should have said 200a panel breaker. No idea on the busbar. Will have to figure that out.
I do have a Square D panel 40MW225. So, I'm guessing that means 225a bus bar.
Actually, I have two 40MW225s.
Truly embarrassing that I have an electrical...