This can be at best, delayed gratification, but I at least have photos of the adventures, whereas I don't have any of the "sand" level tasks I've done - they were done prior to me being aware of the existence of badge bits, and usually completed too quickly to get pics...
(Disclaimer) This install is a paid job I did for a client recently. I am a professional IT consultant and technician.
A client is running a startup business, housing their servers in their (residential) basement. I've never met most of the employees, as everyone works remotely, but the residential grid power isn't always the most reliable, and they found out the hard way, that their typical computer UPSs would only keep the servers running for about 15 minutes. After an hour and a half downtime, they decided to seek my help/advice. There's a small standby generator, but it's only sized to keep the sump pumps running and the furnace. It preceded the startup, and the property owner didn't want to replace it with a higher capacity one.
I measured their power usage for the server room (I think that's one of the lower tasks, but I don't have any pics of that part), and I proposed an expandable "DIY" version of a powerwall, because they mentioned that they needed to expand their server capacity to keep up with their business growth. They were drawing about 5Kw, just from the server room, so I suggested a 6Kw system that could be expanded by adding more units and networking them. We discussed their preferred up-time (hours, not minutes), and where the powerwall could/should be installed. Initially, the server room was supplied by 2x 20 amp 120V branch circuits for the servers, and a 30 amp 240V circuit for the minisplit AC system that cooled the room. Their planned expansion would increase their power usage to possibly 8 Kw.
I ended up installing a 100 Amp sub-panel to supply the inverter(s) - allowing for the planned expansion, a manual transfer switch (to be able to do maintenance on the inverters and bypass them while keeping the servers running, and a load-side breaker box for the branch circuits of all the server room equipment. I also installed a new light fixture in the space, to make it easier/safer to work in the room, and a separate 20 amp GFCI outlet on its own breaker, mostly for tool/utility use in the space. If I can find pics of that, I'll post them to the lower level task threads...
All high voltage wiring in this area, is required to be in metal conduit, so new conduit runs were needed. I hadn't previously ever worked with bending 1" EMT conduit, so that was an adventure and a learning experience for me. I did have a helper, but as they were skittish about working on high voltage, they worked on assembling the battery boxes while I worked with the conduit, the hydraulic knockout cutter, populating the breaker boxes and connecting the AC wiring.
They helped with the heavy lifting to mount the unit on the wall, and pulling wires through the conduit, among other things that aren't relevant to this submission.
The lithium iron phosphate batteries were ordered directly from a Chinese supplier, prior to the tarrif wars, as were the first 2 battery boxes. The initial system capacity was 6 Kw continuous and 32 Kwh battery storage. The following year (6 months later) they decided to go thru their planned upgrades and a second inverter was installed, along with 2 more battery boxes, bringing the system capacity up to 12 Kw and 64 Kwh of battery capacity. The initial system proved itself well, as there was a 4 hour 19 minute outage during a major storm, where the residents were out of town, got notified by the utility company of the outage, and couldn't do anything about it... The system ran flawlessly and none of the remote users even knew that power was out!
After that, they accepted my recommendations to expand the battery capacity to 4 boxes, as the inverter capacity can be independently expanded, separate from expanding the battery capacity.
It's hard to assess how much of the time was spent on the powerwall part, as there was a lot of other things going on during this project. The relevant processes we went through were:
1) site location and capacity planning {30 minutes}
2) installing new conduit for the sub-panel feeder {2 hrs}
3) locating/mounting the sub-panel {30 minutes}
4) pulling wire from the main breaker box 60' to the sub-panel {45 minutes}
5) locating/mounting the bypass transfer switch and load breaker box {60 minutes}
6) installing new conduit from the server room for the branch circuits, since we were moving them to the new load panel
through the existing walls/ceiling {4 hrs}
7) running wiring and installing new breakers to bring mission-critical systems back online {1.5 hrs}
(We'd gotten permission for a 24-hr maintenance window, to shut everything down for this, with the promise that everything would be back up in 24 hrs, and that future expansion wouldn't cause additional downtime. During this window, several of the rackmount cabinets were rearranged to make more room for more servers and more conventional UPSs, in addition to installing operating systems on the new servers in an adjacent room, replace aged UPS batteries on the old UPSs, install the new UPSs, etc. Most of that isn't documented here because it's not relevant to the BB)
After the power was restored to the server room, we could install the inverter and batteries with less pressure to "get back up ASAP, so we took the night off and came back the next day. We did build a rolling platform for the battery boxes, because of their weight, but that time isn't relevant to this submission.
installing the plywood mounting board with blocking behind it {60 minutes}
9) installing the concrete backer board (the inverters are supposed to be installed on a non-combustible surface) {15 minutes}
10) mounting the inverter on the wall {10 minutes}
11) running wiring for the inverter supply and load {30 minutes}
12) making custom battery cables {30 minutes}
13) connecting the batteries to the inverter, and bringing it online {2 hrs}
14) testing power outages to see if the system works {5 minutes}
Some time afterwards, we were called to upgrade the server room with more servers, which required adding 2 new 30 amp branch circuits to the load panel, the related new conduit, an additional inverter, and a pair of additional battery boxes. I include a picture of the expanded "DIY" powerwall setup, although I don't think it's a hard requirement for meeting this BB.
