What is the Tesla mounting bracket seismically rated for single-stacked? Of course double-stacked++ needs to be ground-mounted.
The installer said each power wall weighs approximately 275 lb. and must fasten to two studs. As directed by the electrical lead to avoid pilot holes to find the stud to maintain the fire rating, he found and hit the both studs straight on. The walls typically follow the Uniform Building Code to withstand loads. The packs seems to mount similar to flat panel TVs. For ground mount the pack was put on a 4" thick foam pad, then the pad was pulled and the pack latched to the bracket.
All in all, amazed it was done in a single day. An hour was spent waiting for project manager to drop by to clear up a topic relating to the team being unprepared for hidden conduit installation. This ended up being a good thing as it gave me time to digest the mount height restrictions, fire rating aspects, and realized there wasn't much value added with a hidden conduit up-charge. The Wall Connector being installed tomorrow have the same issue with the fire rated wall for hidden conduit. The gateway and backup load center is to be back to back. The backup load center is replacing the existing garage subpanel, and the existing 2-inch conduit to service panel 3 ft away was sufficient. I definitely did not want to trigger the "hidden conduit" up-charge to only run wire thru the ceiling plumbing soffit. 8 hours of actual work by a 2 man crew. Given labor rates as they are, installation prices have grown to at least cover 16 hours of total labor. The Wall Connector installation labor, in today's prices, is the same cost as the Wall Connector installation.
As for other deviations to what was expected and planned:
1. I was not expecting the Clipper Creek 32A charge station to be backed up, but they landed the breaker into the 200A backup load center. Per the norm, the load was under 60A for two Powerwalls. The corollary benefit is that I didn't not need to add a NEMA 6-15 or NEMA 6-20 to charge cars using backup power during an outage. As a customer sanity check, with load calculation in my head I have room for this in the panel. As another sanity check, in practice, I know what my loads are from a full-on load test, confident I will not fault out the Powerwall system.
2. I was very amazed that Tesla did a 1:1 swap of my 125A subpanel with Tesla's backup load center. The electrician was able to match drill two existing conduits (one to the service and one to the EV charger which I put in with permit). The best part was no additional conduit what so ever for the gateway and backup load center. The gateway is a box with no breakers, and no generation panel. Simply one surface mount gate outside. Super clean and didn't need WiFi and didn't need to tie into Cat 5e. Elegant. Perfect, I didn't need hidden conduit for this.
3. The breaker schedule wasn't laid out or conveyed. Very likely creative license given to the electrical lead. This is the case where lack of plans is actually good to allow the field to make decisions.
4. Initially wanted to mechanically interlock the Wall Connector vs. the Clipper Creek. Now that the panel changed, the interlock won't play nicely. Tesla moved every small load (even landscape lighting) to the backup load center, which is a bonus. As planned, the A/C and Wall Connector will not be backed up.
5. I was hoping to have only 5 disconnects/throws, but there are 6. No real room for a whole house surge protector.
I hope this is insightful.
