EG4 48v PowerPro all weather batteries (two) 28K...OR...EG4-LL (six) 30K rack mounted.....with (two) 6000XP inverters

[energyhunter]

Summary: DIY first system running about one year, thanks to SS and Will Prowse: Upgraded two EG4 6500s, FROM 120v CL panel TO 240v split phase for ALL loads, utility only for back up; equivalent of SBU. Never selling power back to grid, so I chose two 6000XPs (purchased) instead of a single 18K. I will build a ground array with bifacial panels 395k ea or up to 470k ea if bifacial kicks in fully. (Unless y'all have a better idea.) East Tennessee sunshine is about 5.3 and average for panels tilt is 30 degrees.

Question (1) Wouldn't the two PowerPros (about 28K of storage) be adequate for this system? (EG4 has the firmware to adapt it), versus spending $2,000 more for the rack mounted six EG4LL-S (about 30K of storage)? The two PowerPros will be properly mounted outside the shed wall and the two 6000XPs will be inside that shed with the year round 9k mini split.

Question (2) Is 4 Gauge wire sufficient?
Distance from MAIN to new whole house panel in workshop/shed is about 75 ft. I purchased 85 ft of 4/3 copper NM cable for that run through schedule 80 electrical PVC mounted in the crawl space underneath the floor joists; runs about 70 ft plus 10 ft is buried one ft deep between house and workshop. House is 1500 sq ft w/average 120/240 circuits, includes 3 ton heat and A/C and workshop is 16 x 24 (384 sq ft) to have mostly 15a and 20a circuits. Very short distance to array so 10 gauge PV wire should be okay....

I'm sure I made some embarrassing errors here so am open to ALL suggestions and yes, I will have an electrician check my work. Safety is so important to me and I will try to adapt to the NEC for that reason; This is an unincorporated area, county only. Still not sure about a transfer switch.

 

[DIYrich]

I think pvc has to be buried 18 inches. Maybe 24. I think 4 awg wire is 80 amps.

 

[energyhunter]

I think pvc has to be buried 18 inches. Maybe 24. I think 4 awg wire is 80 amps.

Maybe someone can nail this down about the depth. ?? I thought I read somewhere that certain cables without PVC can be buried without conduit as long as they are 24 inches or more. The most shallow allowance I think was 12" in schedule 80 pvc conduit (grey, the thick stuff) but I am not certain. It also must be clearly marked above ground.

About the wire gauge with an 80 ft run, I think the breaker at the main will be 60 amp DP. I hope you are right about the 4 gauge because I paid over $700 for 85 ft of 4 gauge (4/3) cable. Thank you for your reply DIYrich.

 

[TM48]

FYI NEC doesn't allow NM cable in wet locations as in buried conduit. The conduit should be at least 18 inches down. As for the ampacity it depends on the exact type of cable.

 

[energyhunter]

Until someone knows for sure, I will be burying that 10 ft section of cable within sealed schedule 80 electrical pvc conduit at least 18". (East Tennessee.) This is the cable I have. You can see the 10 ft section between the house and the shed. Thank you TM48.

 

[Quattrohead]

I would go with the two power pro batteries and put them inside the shed too. Cost and convenience over rack batteries.
4 AWG, breakered appropriately should be fine for your feed but I do not think it will fit in the terminals of the 6000 XP, would it be okay to assume you would use a small breaker panel to combine the outputs of the 6000 XP together. This is kind of duplication as the inverters already have breakers built in but it is a very convenient way of combining them and gives you extra options for isolating one if you want to.

 

[millsan1]

I like my rack mounted, batteries, but if I started over I would go with the Power pro for sure.

 

[energyhunter]

I would go with the two power pro batteries and put them inside the shed too. Cost and convenience over rack batteries.
4 AWG, breakered appropriately should be fine for your feed but I do not think it will fit in the terminals of the 6000 XP, would it be okay to assume you would use a small breaker panel to combine the outputs of the 6000 XP together. This is kind of duplication as the inverters already have breakers built in but it is a very convenient way of combining them and gives you extra options for isolating one if you want to.

Good comment on the two PowerPro batteries. I checked the manual and the spec sheet but could not determine if the 4 AWG would fit the terminals. The small breaker panel idea for combining the two outputs for the two inverters might be practical for isolation as you say; Wasn't Will's setup like that? Thank you Quattrohead, great comments.

 

[energyhunter]

I like my rack mounted, batteries, but if I started over I would go with the Power pro for sure.

That is more points in favor of PowerPros. Thank you millsan1!

 

[DIYrich]

Maybe someone can nail this down about the depth. ?? I thought I read somewhere that certain cables without PVC can be buried without conduit as long as they are 24 inches or more. The most shallow allowance I think was 12" in schedule 80 pvc conduit (grey, the thick stuff)

RMC is 6", pvc is 18", direct burial is 24".

Underground Electrical Installations | Residential Electrical Installations | Commercial Electrical Installations.

Learn more about underground electrical installations. JADE Learning provides comprehensive courses on commercial and residential electrical installations.

www.jadelearning.com

If you limit to 120v, 20 amps, and GFCI protected, then 12" direct burial.

Digital Codes

ICC Digital Codes is the largest provider of model codes, custom codes and standards used worldwide to construct safe, sustainable, affordable and resilient structures.

codes.iccsafe.org

 

[energyhunter]

RMC is 6", pvc is 18", direct burial is 24".

Underground Electrical Installations | Residential Electrical Installations | Commercial Electrical Installations.

Learn more about underground electrical installations. JADE Learning provides comprehensive courses on commercial and residential electrical installations.

www.jadelearning.com

If you limit to 120v, 20 amps, and GFCI protected, then 12" direct burial.

Digital Codes

ICC Digital Codes is the largest provider of model codes, custom codes and standards used worldwide to construct safe, sustainable, affordable and resilient structures.

codes.iccsafe.org

Looking at both the illustration and the ICC Digital Codes, unless I've missed something, 18 inches would be the appropriate depth. As an aside, this is a walking area with no access for vehicles. The water line is buried 1-2 feet to the right of the proposed cable and it's entry to the house can be seen from the crawl space under the house. There is no gas or propane and the electrical main panel is fed overhead from the other side of the house. This is what I needed to see......Thank you DIYrich!

 

[ksmithaz1]

PowerPro vs Rack: Depends on mounting, and how much battery you expect to end up with. My next battery purchase I will likely replace the racks I have with two taller Ruixu's that hold 10 units. This puts 100KWH in 7 feet x 4 feet x 4 feet. If you have unlimited wall space or modest needs the power-pro will present a much more asthetic solution. There is also the maintenance aspect, pretty simple to pull and swap a rack-mounted setup.

Then again in 5 years we may have new tech, that makes this all obsolete.

 

[hwy17]

I would want the powerpros. Less batteries less problems.

 

[G00SE]

Everyone should have a few of each

 

[energyhunter]

PowerPro vs Rack: Depends on mounting, and how much battery you expect to end up with. My next battery purchase I will likely replace the racks I have with two taller Ruixu's that hold 10 units. This puts 100KW in 7 feet x 4 feet x 4 feet. If you have unlimited wall space or modest needs the power-pro will present a much more asthetic solution. There is also the maintenance aspect, pretty simple to pull and swap a rack-mounted setup.

Then again in 5 years we may have new tech, that makes this all obsolete.

Since there is rather limited space inside my workshop I am inclined to mount both PowerPros outside where they were ideally designed to be; With that said, I can always change my mind. If you accumulate 100KW it is likely you've done the math and can utilize that kind of power for your particular needs. I might add additional power storage over time. As fast as tech changes one can habitually off a grid back up, but sooner or later you have to dive in. Ironically my grid power went off last week while I was on hold to make a purchase from Signature Solar. I also lost my AT&T cell phone service the same day my Pharmacy was Cyber attacked and could not fill a prescription. There are those who would make ME obsolete.....

 

[energyhunter]

I would want the powerpros. Less batteries less problems.

The BMS may be better with the PowerPros.....?

 

[hwy17]

The BMS may be better with the PowerPros.....?

Signature will stand by both, but the Powerpro is newer and getting more development attention right now probably.

 

[energyhunter]

Everyone should have a few of each

If I remember correctly, years ago someone in the crowd surrounding Rockefeller in the streets of New York shouted out to him, "How much is enough?!?" He answered, "Just a little bit more!"

 

[energyhunter]

Signature will stand by both, but the Powerpro is newer and getting more development attention right now probably.

Yes, my experience with Signature Solar has proven that they are trustworthy and reliable for additional purchases. They are growing fast for a reason so I don't mind waiting in line for tech or customer help because they always come through for me. There are some other good solar resources too but proximity is a factor.

 

[ksmithaz1]

I think BMS is one of those diminishing return things. At some point you should pretty much get it right and not really need any more firmware upgrades as long as the BMS hardware is the same. Powerpro is getting more attention because it's NOT as stable, not because it is.