Advice requested: wall connector & pedestal install

[YRide]

Looking for advice from anyone that’s done a standalone pedestal install!

1) How deep does the concrete pad need to go?

2) How wide?

3) Did you go with a) a rectangular form to perfectly match the base of the pedestal (9.75”x7”), b) a larger rectangular form then the pedestal base or c) a round form like a Sonotube?

4) does anyone who lives in San Jose hsve 3x EVSE? Thought I saw only 2x were allowed per house.

5) also for SJ people…if mounted next to (on the side) the driveway…do bollards or parking curbs need to be installed?

6) if I used Sch40 1” PVC, is there a requirement on trench width? Or just trench depth? Was planning to use a handheld georipper to hug just inside the properly line and keep as narrow as possible…this is a narrow 2” wide trench, and I would go down 18” to the top of the PVC, so 19-20” trench.

7) if I included a separate home-run with Romex 12/2 to the same pedestal for a new 120v gfci receptacle with 20A OCPD, is it ok to do that in the same conduit? If I did the math right…I have 4x #6 STR CU THHN and 3x #12 STR CU THHN…for a 28.06% fill capacity with 1” Sch40 PVC.

8) is it correct understanding that even though the ground wires on the #6 and the #12 are not considered “current carrying” that they still are considered for the fill capacity calculation? I was wondering if I could drop to 3/4” Sch40 PVC and still meet NEC?

9) do I need to use rigid Sch40 1” PVC? Or is it acceptable to use flexible Sch40 1” PVC? It seems like flexible will make it easier for me to route the conduit under the concrete and around the shrub roots.

10) my plan is to drop the circuit from the eve of the house (via non-human-accessible soffit) down the side of the house straight into the concrete walkway…then under the walkway (4’) to to edge of the property (another 2’ from walkway to property edge)…then along the edge of property edge (20’) to the concrete pad for the pedestal mount. When I go straight into and under the stamped concrete walkway…I’m hoping to avoid cutting a trench into it…and would like to go under it via as small a hole as possible. If I do this…and the walkway is >4” thick…does that mean that my burial cover requirement is only 4” (basically, just under the 4” think concrete is ok per NEC table 300.5)? Or is that only if the entire installation stays under the slab, and since my installation will eventually go to the property line in an 18” trench…then I still need to ensure the conduit is >8” under the 4” concrete walkway (so >12” cover per table 300.5)?

11) is there any code requirements requiring J/L-bolts embedded in the concrete? Or could anchors be used after the fact? What did you use?

 

[lodar]

4) does anyone who lives in San Jose hsve 3x EVSE? Thought I saw only 2x were allowed per house.

My house was built with 3 EVSEs over 2 circuits (a pair are load sharing a circuit), they were clearly marked on the plans and passed permitting. Albeit, it was via Santa Clara County. This is the 1st time I have heard of such a specific limit. San Jose city council were just tooting their horns about having more EVSEs in apartments, I don’t see why they’d be trying to artificially limit them in homes.

HOWEVER… a more common limitation is a house’s electrical load capacity. But even then, you can have multiple EVSEs load share the same circuit. In the extreme, SFO Long Term Parking has something like 8-16 EVSE load sharing a circuit, rotating through charging cars.

 

[YRide]

My house was built with 3 EVSEs over 2 circuits (a pair are load sharing a circuit), they were clearly marked on the plans and passed permitting. Albeit, it was via Santa Clara County. This is the 1st time I have heard of such a specific limit. San Jose city council were just tooting their horns about having more EVSEs in apartments, I don’t see why they’d be trying to artificially limit them in homes.

HOWEVER… a more common limitation is a house’s electrical load capacity. But even then, you can have multiple EVSEs load share the same circuit. In the extreme, SFO Long Term Parking has something like 8-16 EVSE load sharing a circuit, rotating through charging cars.

Thx for the data point. While maybe not applying to SJ AHJ, I guess that’s promising…everyone says Santa Clara County AHJ is the most extreme!

I found the reference to limiting 2 EVSE for level 1 or level 2…Electric Vehicle Charging Stations | City of San José

Actually, my understanding in talking with SJ inspectors is that per the CEC, you can NEVER load share a circuit for an EVSE in California. So each EVSE has to have its own dedicated home-run back to the main painel (or I guess a sub panel). However, an EVSE with a UL-listed “power sharing” mode (like the Tesla wall chargers have) can allow you to set a combined current maximum, so to your last comment…you can almost always make sure it fits into an approved load calculation.

I did point out to the AHJ that Tesla installation instructions seem to indicated you could install multiple EVSE on a single circuit, but still not approved (at least here). AHJ did indicate they would dicuss this with team, and get back to me. See page 33 of this https://digitalassets.tesla.com/tes...-Wall-Connector-Installation-Manual-NA-EN.pdf

Anyways, appreciate sharing your situation. Btw, any idea when those plans and permits went through for your experience with SCC? Recently?

 

[lodar]

I found the reference to limiting 2 EVSE for level 1 or level 2…Electric Vehicle Charging Stations | City of San José

That is “Level 1” (120V) or “Level 2” (240V) NOT “1 or 2 EVSE”. It is a roundabout way to say “No Level 3/4 Tesla Superchargers / ChaDeMo / CCS” (400V+).

It is one of those weird Oxford Comma moments:

Residential properties may have only Level 1 or 2 charging stations.

“Level 1 or 2” then “charging stations” meaning as many as you want just stick with Level 1 or Level 2.

It doesn’t make sense to read it as “Level 1” or “2 charging stations of any kind”. That means I could pack 2 Tesla Superchargers into my garage.

I did point out to the AHJ that Tesla installation instructions seem to indicated you could install multiple EVSE on a single circuit, but still not approved (at least here). AHJ did indicate they would dicuss this with team, and get back to me.

FWIW… I successfully installed 1st Gen Tesla HPWC with wired load sharing with the comms cable. Permitted and inspected in my old home back in 2016 (City of San Jose) and again 2020 (SCC).

any idea when those plans and permits went through for your experience with SCC? Recently?

Submitted 2019, Approved 2020, Completed 2021.

SCC kinda forgot our permits, and kept saying it was being worked on, until we pointed out the 1 year anniversary of the submission.

Then COVID-19 struck.

 

[YRide]

That is “Level 1” (120V) or “Level 2” (240V) NOT “1 or 2 EVSE”. It is a roundabout way to say “No Level 3/4 Tesla Superchargers / ChaDeMo / CCS” (400V+).

It is one of those weird Oxford Comma moments:

“Level 1 or 2” then “charging stations” meaning as many as you want just stick with Level 1 or Level 2.

It doesn’t make sense to read it as “Level 1” or “2 charging stations of any kind”. That means I could pack 2 Tesla Superchargers into my garage.

FWIW… I successfully installed 1st Gen Tesla HPWC with wired load sharing with the comms cable. Permitted and inspected in my old home back in 2016 (City of San Jose) and again 2020 (SCC).

Submitted 2019, Approved 2020, Completed 2021.

SCC kinda forgot our permits, and kept saying it was being worked on, until we pointed out the 1 year anniversary of the submission.

Then COVID-19 struck.

Yes, re-reading the SJ website you are correct, it’s just limiting the level of EVSE, not the qty. great!

As for the multiple EVSE’s sharing a branch circuit…this is what I was referred to by SJ folks.

…

In doing a little research it looks like the NEC did amend for the NEC 2023 code cycle, amending 625.40 and adding 625.42A/B which now allow for multiple EVSE on a single branch circuit with an approved Energy Mgmt System (EMS).

However…CA is currently on the CEC 2022 (went into effect 1/1/2023) and that is leveraging the older NEC 2020.

So my thinking is it’s still not technically code compliant. But I guess ultimately the AHJ gets to determine what is ok or not?

 

[h2ofun]

Yes, re-reading the SJ website you are correct, it’s just limiting the level of EVSE, not the qty. great!

As for the multiple EVSE’s sharing a branch circuit…this is what I was referred to by SJ folks.

View attachment 1009008
…
View attachment 1009012
View attachment 1009009

In doing a little research it looks like the NEC did amend for the NEC 2023 code cycle, amending 625.40 and adding 625.42A/B which now allow for multiple EVSE on a single branch circuit with an approved Energy Mgmt System (EMS).

However…CA is currently on the CEC 2022 (went into effect 1/1/2023) and that is leveraging the older NEC 2020.

So my thinking is it’s still not technically code compliant. But I guess ultimately the AHJ gets to determine what is ok or not?

Since I have 5 wall connectors installed,

 

[YRide]

Do all 5 of your wall connectors have dedicated/separate branch circuits? Or are any of the 5 EVSE sharing a circuit?

What AHJ are you in?

 

[h2ofun]

Do all 5 of your wall connectors have dedicated/separate branch circuits? Or are any of the 5 EVSE sharing a circuit?

What AHJ are you in?

I ran a 200 amp tap to a new subpanel. I then drove seperate lines from there. I could program them so it would be limited, but I just know one would never really want to use maybe a most 2 at a time. I just wanted them so cords would not have to be run all over the place depending on where an EV is parked.

 

[YRide]

I ran a 200 amp tap to a new subpanel. I then drove seperate lines from there. I could program them so it would be limited, but I just know one would never really want to use maybe a most 2 at a time. I just wanted them so cords would not have to be run all over the place depending on where an EV is parked.

Ok, so I guess the sub panel part would have been in theory ok….but your tap would have need to have been 5x60A=300A, right?

Or you could just set the EMS to have a max of 160A (160A @ 125% for EVSE = 200A). But that doesn’t appear to be approved for CA until they update to the 2023 NEC code cycle.

Only stating from a code/inspection point of view. Clearly if you only have 2x EV’s, even with 5 EVSE…than you’re probably never getting even close to the limit.