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SRNE 20KW parallel ASP journey.

Nice tip, thank you.

I have but I'm going to redo it again or at least make some modifications when I add the 5th pack.
I threw it together in haste knowing I'll be adding another pack(s) in the fall.
I need to move the front bottom layer to the top because I didn't account for the bottom shelf being shorter than the top layer, the row barely fits.
The straps are bugging me too.
.... I can do better ...
Wow, that's a lot of power under those inverters! Hate to see a wrench dropped on one of those busbars..

What's the Ah on those new batts? Are the straps adjusted to a certain tension, or are you trying to just keep the cells from expanding too much?

I've seen that those new MB31 cells are out, rated at 314Ah. You can get them now for $105 at 18650 battery store.
 
Nice tip, thank you.

I have but I'm going to redo it again or at least make some modifications when I add the 5th pack.
I threw it together in haste knowing I'll be adding another pack(s) in the fall.
I need to move the front bottom layer to the top because I didn't account for the bottom shelf being shorter than the top layer, the row barely fits.
The straps are bugging me too.
.... I can do better ...
Trying to come up with ideas for a diy battery shelf, cabinet, kind of thing welded from mild steel, or possibly aluminum, that allows easy access to the individual cells in the banks. At first was thinking a modular lego stacking kind of approach, think connex boxes stacked on top of each other, but with each cell weighting ~10lbs, and w/16cells+box, that would be a lot for one person to lift each assembly off to reach a lower bank of cells. Now wondering about heavy duty shelf sliders for each bank that would allow each bank to be opened like a cabinet drawer.

Ideas?
 
Wow, that's a lot of power under those inverters! Hate to see a wrench dropped on one of those busbars..
Yea, I'm going to add a top too. I like to live dangerously but I'm growing up.😂
What's the Ah on those new batts? Are the straps adjusted to a certain tension, or are you trying to just keep the cells from expanding too much?
1045AH - 2 230AH, 1 305AH, 1 280AH.
I'm going to parallel the 230AH when I add another pack.
Just trying to keep them restrained, cinched hand tight at low SOC.
I need to get some proper ends plates.
I've seen that those new MB31 cells are out, rated at 314Ah. You can get them now for $105 at 18650 battery store.
That's a darn good price. I've considered them for the next pack.
Trying to come up with ideas for a diy battery shelf, cabinet, kind of thing welded from mild steel, or possibly aluminum, that allows easy access to the individual cells in the banks. At first was thinking a modular lego stacking kind of approach, think connex boxes stacked on top of each other, but with each cell weighting ~10lbs, and w/16cells+box, that would be a lot for one person to lift each assembly off to reach a lower bank of cells. Now wondering about heavy duty shelf sliders for each bank that would allow each bank to be opened like a cabinet drawer.

Ideas?
I think @Zwy has the best approach with the repurposed cabinet.
I've player a bunch out in my head and keep coming back to that.
 
Now wondering about heavy duty shelf sliders for each bank that would allow each bank to be opened like a cabinet drawer.
I thought about this as well - use full extension drawer glides with 200 lb rating to support a small angle iron frame that the pack can just sit in.
For most things, pulling out the 'drawer' and removing the top of the pack would give you access to all the cells.
If more needed to be done, you could lift out the pack from the angle frame.

The reason I didn't do it: (yet)
My packs are 27" front to back - and to clear other items I would need 30" glides x 8 sets = expensive.
Wires and things need to be out of the way of the full extension glides, so they don't attempt to be load carrying conductors.
If you/someone pulled out more than one or two "drawers" the whole works could tip. I guess bolt it down but just saying.
Once I had all the cells and packs balanced, it seemed unnecessary to have quick access anymore.
Maybe when I upgrade to twin 12kW inverters...
 
I think @Zwy has the best approach with the repurposed cabinet.
I've player a bunch out in my head and keep coming back to that.
Currently working on the cabinet for the shop and this cabinet is slightly larger. Same height but is about 8 inches deeper and 10 inches wider. If you are looking for one, find one that is 60" wide and about 20" deep. This makes it so much easier to run everything.

I'm busy with building the array at the moment.
 
Almost a perfect curve. I need to buy an EV...
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ASPs have been flawless.
Dude what are all those 7k load spikes? Is that top chart out of SA?
 
No idea why I can't delete you quote .
Dude what are all those 7k load spikes? Is that top chart out of SA?
Could have been the stove, oven, or dryer and the well pump. A lot of cooking and laundry and laundry was getting done.

Yes, you can tap the chart to get a menu at the top that lets you share that chart, then you can select background color.
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@42OhmsPA Are you running the NE Solar 370W panels to the MPPT's?

Originally I had planned on 20 or 21 panels for the large array using 1/2 of the used tornado damaged MT Solar mounts I bought cheap. Configuration was landscape 4x5 with the odd panel somewhere if I used 21 panels. 7S configuration, 3 strings or a pair of 7S and one 6S.

Over the weekend I started to build the base for the array, poles have been in over a month and I just finished the video highlights of that today. Originally these mounts were single pole with 3x5 configuration. I'm using 2 poles and planned on the 4x5. But after getting the center frame sections all bolted together I thought I can add a wing on each end and have 5x5, so 25 panels total. The wings are extras as I combined the mounts and these would have been on the ends, I only have to bolt them on. I had some concerns with clearance on the sides for moving equipment past the array and that is why I originally planned on only 22.5 feet width, the added 3.75 feet long wings will add 7.5 feet.

With 5x5, that means most likely one 7S string and three 6S strings. My question is about combining probably a pair of the 6S and what you have been running for MPPT strings. 9S would put me over on VOC when it is -30°F here, 8S would work but what about the extra panel? 7S works for single strings but overpanels the MPPT if combining 2 parallel strings (and you know what I think about over paneling if you have enough MPPT's) but only 180W of over paneling so not a big deal. 6S with 2P to one MPPT works out well and leaves one MPPT still open with one 7S and the other 6S each using one MPPT.

How did you run your strings?

I'll still have 6 panels left, will have to buy more panels to use those up. :ROFLMAO:
 
@42OhmsPA Are you running the NE Solar 370W panels to the MPPT's?

Originally I had planned on 20 or 21 panels for the large array using 1/2 of the used tornado damaged MT Solar mounts I bought cheap. Configuration was landscape 4x5 with the odd panel somewhere if I used 21 panels. 7S configuration, 3 strings or a pair of 7S and one 6S.

Over the weekend I started to build the base for the array, poles have been in over a month and I just finished the video highlights of that today. Originally these mounts were single pole with 3x5 configuration. I'm using 2 poles and planned on the 4x5. But after getting the center frame sections all bolted together I thought I can add a wing on each end and have 5x5, so 25 panels total. The wings are extras as I combined the mounts and these would have been on the ends, I only have to bolt them on. I had some concerns with clearance on the sides for moving equipment past the array and that is why I originally planned on only 22.5 feet width, the added 3.75 feet long wings will add 7.5 feet.

With 5x5, that means most likely one 7S string and three 6S strings. My question is about combining probably a pair of the 6S and what you have been running for MPPT strings. 9S would put me over on VOC when it is -30°F here, 8S would work but what about the extra panel? 7S works for single strings but overpanels the MPPT if combining 2 parallel strings (and you know what I think about over paneling if you have enough MPPT's) but only 180W of over paneling so not a big deal. 6S with 2P to one MPPT works out well and leaves one MPPT still open with one 7S and the other 6S each using one MPPT.

How did you run your strings?

I'll still have 6 panels left, will have to buy more panels to use those up. :ROFLMAO:
Currently on the 1st ground mount I'm 7S2P with the NE solar 370W and I see a fair amount of clipping at 22A, I plan to split this into 2 strings for winter.
The roofs are 9S2P S and W 315W Q Cells but they are angled poorly for winter, I've seen this mppt maxed out a few times in the summer but I don't need that extra power so I'm not worried about the 170W overage.
The next ground mount will be an 8S or or 9S setup with the 370W NE Solar, leaning towards a 3x3 layout.

Ground mount is inverter 2 in the attached.
 

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Currently on the 1st ground mount I'm 7S2P with the NE solar 370W and I see a fair amount of clipping at 22A, I plan to split this into 2 strings for winter.

That answers my question. I thought it would probably clip with 6S2P as that will be 22A, just lower VOC. It could be you are hitting the limit on MPPT rated capacity, it is 5500W each. I'm not big on running things at full capacity anyway.

I have a few thousand feet of 10AWG already so adding another string isn't a problem as the array is about 70 feet from the shop. But down the road it changes things if I want to add on as all MPPT's will be used unless I use 8S and leave the one panel not connected.

The roofs are 9S2P S and W 315W Q Cells but they are angled poorly for winter, I've seen this mppt maxed out a few times in the summer but I don't need that extra power so I'm not worried about the 170W overage.
The next ground mount will be an 8S or or 9S setup with the 370W NE Solar, leaning towards a 3x3 layout.

Has to be warmer there in winter than here. I had run the specs thru the Midnite calculator for -30°F and VOC gets up there. It gets dang cold here in winter mid January usually.
 
I am running x10 325W Ja Solar and x11 325W Ja solar to my ASF. My roof is 210°SW at (4/12) 26.6° pitch. It is pretty much setup for winter, but I have seen 115% output (7.89kW) this month on a crazy cloudy/sunny day, but most of the time I max out at 4-5kWh. Both arrays/MPPTs are way below the 5500W and 22A limit. The highest total for a day I have seen is 21kWh, but I have to really work to use that much. My batteries are almost always full before noon. It will be interesting to see how well it does in winter.

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I've decided on the array and will be adding the wings but leaving off one lower panel. I have to push snow past the array in the winter and that was the reason I originally planned on a 4x5 array in landscape. It also was one of the reasons I did not use Sinclair as I needed height for the array, not width.

Array will be 5x5 with one lower panel off so 24 panels in 8S strings. VOC at -30°F will be 385V. This leaves 7 panels left and I was planning on 21 panels with 7S with the narrower mount. I'll use those 7 panels someday on another mount. I will have an extra MPPT I won't be using either. With the one panel left off that column, it makes it much nicer to drive past with higher ground clearance on that lower corner.

One more thing is the 17' Iron Ridge rails need extensions and I'll get 80" total cut off the bottom of 2 rails which will work for the extensions.

The poles and foundation cost the same whether I install 20 or 24 panels.

All around win on this idea.
 
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Ok, totally newbie question but I am trying to figure out if these ASP 10kw would work for me.

Monitoring our usage shows that we do sometimes pull as much as 80 amps. If I have 2 of these paralleled, and had no PV or battery power available, I would be able to push 63 amps in bypass from each inverter to a combing panel for 126 amps available total to our distribution panel? Is that correct? Or is the bypass limited to the capacity of the inverters (20kw total)

And if I have an 80 amp draw, and only have 40 amps available in PV/battery, does the inverter switch to grid bypass for all of that load or does it blend what I have available in PV/battery along with the grid?

Sorry for the newb questions. Just want to make sure I understand before I make any purchases.
 
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Ok, totally newbie question but I am trying to figure out if these ASP 10kw would work for me.

Monitoring our usage shows that we do sometimes pull as much as 80 amps. If I have 2 of these paralleled, and had no PV or battery power available, I would be able to push 63 amps in bypass from each inverter to a combing panel for 126 amps available total to our distribution panel? Is that correct? Or is the bypass limited to the capacity of the inverters (20kw total)

And if I have an 80 amp draw, and only have 40 amps available in PV/battery, does the inverter switch to grid bypass for all of that load or does it blend what I have available in PV/battery along with the grid?

Sorry for the newb questions. Just want to make sure I understand before I make any purchases.
If your in uti mode and have the mix lod set to enable it will provide what it can from the pv and make up the difference from the grid.

4000 watt load > pv providing 2000 watts would make grid provide 2000 watts.

On the amps bypass part the unit can spit out 63 amps per unit. Two units will give you 126 amps. Three would give you 189 amps. Etc.
 

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