EVSE/Wall Charger Load Calcs: San Jose

[YRide]

Trying to install two Gen3 wall chargers / EVSE on a 200A service (Tesla PV & ESS to come later, but they are asking me install and get inspection before they are willing to update the design).

I was advised to use the 220.82/83 "optional" method. Anyone have experience in this?

• House is an existing dwelling, so my understanding is we get to use 8,000 watts (not sure why this is watts and not kVA) @ 100%, 40% for remainder
• We have one laundry room, but somehow have a separate washer & dryer (gas) circuit on our sub panel. I'm not sure both are used...but worst case, that's 2x laundry circuits.
• I can't find nameplates on either of our dishwashers, so left both at 20A*120V=2,400 watts (I think this is overly conservative).
• Our A/C is nameplated for max breaker at 40A, but we actually have it on a 30A breaker. So left it at 40*240=9,600watts to be conservative.
• We are planning to install a 30A*240V electric dryer circuit as part of this work to future proof (but dont plan on using it)...so added 7,200watts for this (does this mean i have to increase the laundry circuits in 3rd row to qty 3?)
• Removing (subtracting) all of the above from our 200A service, I get 15,300watts available for EVSE to keep me under 200A.
• I believe 15,300watts is at 125% though, so really that's 12,240watts of usable power = 51 amps.
• Per 220.83, I believe I can use the Tesla Gen3 Power Sharing, and set it to max 51A for the two EVSE's (but each can reside on a 60A breaker, and charge up to equipment max 48A, one at a time...or really one at 45A and the other at 6A minimum...or whatever the LMS determines).

Did I do that right? The questions I had were...

1. Did I really need to add qty 3 of laundry circuits since I'm adding (now) a 30A/220V circuit? Or should it only be qty 2 (existing circuits...and maybe just one if i find out that one really isnt used)?
2. If I am adding the 30A/220V for future proof for electric dryer, but not planning to use, can I exclude this?
3. Does 2,400 watts per dishwasher seem high? Is it worth pulling them out to try and find the name plate (to give me more headroom for the EVSE max amperage)?
4. Did I correctly state that the 15,300watts headroom I have for EVSE max is at 125%? Or is that what my 100% max is because I'm using a Load Mgmt System?

 

[wwhitney]

I was advised to use the 220.82/83 "optional" method. Anyone have experience in this?

• House is an existing dwelling, so my understanding is we get to use 8,000 watts (not sure why this is watts and not kVA) @ 100%, 40% for remainder

It is kVA in the code, the use of Watts was likely a terminology change made by San Jose either in error or based on the idea that it would easier for the general public to understand, if technically inaccurate. Further comments:

1) If you have only one laundry room, and one circuit labeled "washer/ (gas) dryer" and no other circuit labeled "laundry circuit", that's just one laundry room circuit. They've just labeled the laundry room circuit as "washer/dryer". Also, a 240V circuit for an electric dryer is not a laundry circuit, adding one doesn't increase the number of laundry circuits.
2) 2400VA for a dishwasher is excessive. There's no nameplate visible when you open the door, or maybe behind a removeable toekick cover? No model number to look up the spec sheet? In that case I'd just be inclined to look up a comparable model from the same manufacturer and use its rating.
3) For the A/C, you want to use the MCA (minimum circuit ampacity) number on the nameplate, not the MOCP (maximum overcurrent protection)
4) Dryers are specified as 5000VA or the nameplate if greater. So I'd suggest 5000VA unless you have a model picked out already that has a higher nameplate rating.
5) The SJ worksheet errs in putting the new load on a separate line and figuring it at 100%. The new load is figured the same as the existing load, so it gets the same 40% factor.

Now one consequence of (5) is that EVSEs get the 40% factor. That's objectively unreasonable as EVSEs are a rare continuous load in a residence. So for the limiting case of a residence with little other load, you could end up with (8) 40A continuous EVSEs on a 200A service, which obviously couldn't all operate at once.

So if SJ has amended the Electrical Code to count EVSEs at 100% rather than 40%, that's reasonable. If they haven't amended the Electrical Code to do that, it's semi-reasonable and probably not worth fighting, but also contrary to the letter of the rules.

Lastly, as to the 125% factor for continuous loads, that's not exactly how load calculations work, but it's a conservative approximation that will usually work out the same in practice.

Cheers, Wayne

 

[Vines]

It is kVA in the code, the use of Watts was likely a terminology change made by San Jose either in error or based on the idea that it would easier for the general public to understand, if technically inaccurate. Further comments:

1) If you have only one laundry room, and one circuit labeled "washer/ (gas) dryer" and no other circuit labeled "laundry circuit", that's just one laundry room circuit. They've just labeled the laundry room circuit as "washer/dryer". Also, a circuit for an electric dryer is not a laundry circuit, adding one doesn't increase the number of laundry circuits.
2) 2400VA for a dishwasher is excessive. There's no nameplate visible when you open the door, or maybe behind a removeable toekick cover? No model number to look up the spec sheet? In that case I'd just be inclined to look up a comparable model from the same manufacturer and use its rating.
3) For the A/C, you want to use the MCA (minimum circuit ampacity) number on the nameplate, not the MOCP (maximum overcurrent protection)
4) Dryers are specified as 5000VA or the nameplate if greater. So I'd suggest 5000VA unless you have a model picked out already that has a higher nameplate rating.
5) The SJ worksheet errs in putting the new load on a separate line and figuring it at 100%. The new load is figured the same as the existing load, so it gets the same 40% factor.

Now one consequence of (5) is that EVSEs get the 40% factor. That's objectively unreasonable as EVSEs are a rare continuous load in a residence. So for the limiting case of a residence with little other load, you could end up with (8) 40A continuous EVSEs on a 200A service, which obviously couldn't all operate at once.

So if SJ has amended the Electrical Code to count EVSEs at 100% rather than 40%, that's reasonable. If they haven't amended the Electrical Code to do that, it's semi-reasonable and probably not worth fighting, but also contrary to the letter of the rules.

Lastly, as to the 125% factor for continuous loads, that's not exactly how load calculations work, but it's a conservative approximation that will usually work out the same in practice.

Cheers, Wayne

Many local jurisdictions treat new EVSE as requiring 100% factor, we have decided to use this approach across our load calculations as it does make sense when you think about it a little bit.

 

[wwhitney]

Many local jurisdictions treat new EVSE as requiring 100% factor, we have decided to use this approach across our load calculations as it does make sense when you think about it a little bit.

I agree it makes total sense, but it's not actually adopted into the NEC yet. The code/law is behind reality. Given that the optional load calculation for a residence is already quite conservative, the non-conservativeness of including 1 EVSE at 40% isn't likely to cause the main breaker to trip.

So absent a local amendment, I'd say the most an AHJ can legally do is strongly advise you to count the EVSE at 100% instead of 40%. Of course, they can probably cause you trouble in various ways if you decline to take their strong advice, or just turn you down and dare you to sue them. So in practice they can unilaterally force you to use 100% instead of what the rules say.

Cheers, Wayne

 

[YRide]

It is kVA in the code, the use of Watts was likely a terminology change made by San Jose either in error or based on the idea that it would easier for the general public to understand, if technically inaccurate. Further comments:

1) If you have only one laundry room, and one circuit labeled "washer/ (gas) dryer" and no other circuit labeled "laundry circuit", that's just one laundry room circuit. They've just labeled the laundry room circuit as "washer/dryer". Also, a 240V circuit for an electric dryer is not a laundry circuit, adding one doesn't increase the number of laundry circuits.
2) 2400VA for a dishwasher is excessive. There's no nameplate visible when you open the door, or maybe behind a removeable toekick cover? No model number to look up the spec sheet? In that case I'd just be inclined to look up a comparable model from the same manufacturer and use its rating.
3) For the A/C, you want to use the MCA (minimum circuit ampacity) number on the nameplate, not the MOCP (maximum overcurrent protection)
4) Dryers are specified as 5000VA or the nameplate if greater. So I'd suggest 5000VA unless you have a model picked out already that has a higher nameplate rating.
5) The SJ worksheet errs in putting the new load on a separate line and figuring it at 100%. The new load is figured the same as the existing load, so it gets the same 40% factor.

Now one consequence of (5) is that EVSEs get the 40% factor. That's objectively unreasonable as EVSEs are a rare continuous load in a residence. So for the limiting case of a residence with little other load, you could end up with (8) 40A continuous EVSEs on a 200A service, which obviously couldn't all operate at once.

So if SJ has amended the Electrical Code to count EVSEs at 100% rather than 40%, that's reasonable. If they haven't amended the Electrical Code to do that, it's semi-reasonable and probably not worth fighting, but also contrary to the letter of the rules.

Lastly, as to the 125% factor for continuous loads, that's not exactly how load calculations work, but it's a conservative approximation that will usually work out the same in practice.

Cheers, Wayne

Thx @wwhitney

If power factors are always 1, then kVA = Watts, right? I guess for most practical applications...that will be sufficient. Anyways, won't belabor that.

1) thanks for clarification. I just poked around, moved the washer and dryer (gas). There is a second outlet (in the same laundry room), but it's unused...as both washer and dryer (gas) are connected to the same receptacle. So since I have two breakers, and two outlets, even if only one is used...I assume I should leave qty 2 on the optional load calc (and thanks for educating me that the 30A/220V does not count here). Or could I say I never intend to use the other outlet (turn the breaker off too) and remove it from my load calc?

2) 2,400 watts is excessive, I just want max / conservative on the circuit rating. I just checked one and found the nameplate (namesticker )...it is 2.6A motor load + 8A other...so 10.6A*120=1,272 watts. We don't ever use this one, but it's there. For the primary, its a Kenmore/Whirlpool w10620236 but for the life of me I can not find specifications on it (inside door, kickpanel, etc) or anywhere on internet. I guess i'll have to pull it out.

3) MCA is 27.5, so I'll update that. Can you explain to why MCA is used? Is it because that is the typical sustained load? the OCPD 40A (or in our case 30A) is just there to prevent an OC situation, and would break the circuit immediately, so it's never a sustained load?

4) actually we have no intention at this time, prob in next several years, of moving to the electric dryer. We'll keep using the gas one we have...I just wanted this circuit for the future. So nothing picked out. Do I have to have to include this at 5000kVA simple because the circuit exists and the potential to use it is there, or can i leave blank? Am I anyway double counting this, because it's in the "Added Load" @ 100% at bottom, 30A*240=7,200VA.

5) I'm not sure I got your point. In the SJ sheet (optional method) the EVSE loads are at 100%, not at 40%, right? This makes sense to me (even though as you say it's not in the code...) Are you saying the new load should only get the 40% factor? Or you are saying I am doing it correct, per SJ guidance? I could see an EVSE reasonable charger for >3hrs, maybe not every day, but definitely not "rare". Isn't it about 44 rate miles / hour at 48A on say Model Y, so that's 132 "rate" miles. I think trip from SJ-SF-SJ, driving >75mph would easily cause you to charge at 48A for >3hrs then.

With those adjustments, it gives me headroom to have the Power Shared max now at 78A between the two EVSE. So I can leave them both on 60A OCPD's, and then can use one at max 48A with the other operating at 30A, vice versa, or any other aggregate the Tesla Load Mgmt System deems necessary. This should suit any of my needs.

 

[wwhitney]

1) The NEC requires one dedicated circuit for the laundry area. If you actually have two dedicated circuits, so each of those two breakers just has one receptacle on it, then you would count both circuits. Or if you are using one of them, you could turn the other off and label it unused and only show 1 laundry circuit on your load calc. If one of those receptacles is on a circuit with other receptacles, it's not a dedicated laundry circuit, and is already accounted for in the 3 VA/ft^2.

2) You could just use the values you found for the one dishwasher, the other is probably close. So put down (2) dishwashers, 2600 VA total

3) For HVAC equipment and other motors, the branch circuit OCPD usually doesn't provide overload protection. Its job is to provide short circuit and ground fault protection, and a separate overload protection is typically provided at the equipment/motor. So that allows the OCPD on the branch circuit to be oversized relative to the load and conductors (e.g. with 27.5A MCA and 40A MOCP, you could use #10 copper conductors and a 40A breaker, not normally allowed) Which is good, as it provides more headroom for the branch circuit OCPD not to trip from motor starting surge.

The upshot is that MCA is the spec that is closest to the actual load. If your HVAC equipment started drawing 40A for a significant period, the internal overload should trip.

4) It's up to you whether to show future loads. If you want the most EVSE current you can get now, omit them. If you don't want to have to down size the EVSE in the future, include the future loads. Certainly you wouldn't show the same load twice, once above and once in the "added load".

5) SJ errs in putting "Added Load at 100%" if it means all added loads are to be at 100%. Added loads get the same factors as existing loads. So your added loads should just be mixed in with the existing loads up above. To quote NEC 220.83(A), which has the "first 8 kVA @ 100%, rest @ 40%" rule, "The following percentages shall be used for existing and additional new loads."

Now, if you accept that SJ can unilaterally force a 100% factor for EVSEs, and your only additional loads are EVSEs, then the question is moot. But if you are adding both EVSE and non-EVSE loads, and you accept the 100% factor for EVSEs, putting the new EVSE loads on the "Added Load at 100%" line and put the rest of the new loads up above with the existing loads. You can label the loads above existing or new (or future), if you like.

Cheers, Wayne

 

[YRide]

1) The NEC requires one dedicated circuit for the laundry area. If you actually have two dedicated circuits, so each of those two breakers just has one receptacle on it, then you would count both circuits. Or if you are using one of them, you could turn the other off and label it unused and only show 1 laundry circuit on your load calc. If one of those receptacles is on a circuit with other receptacles, it's not a dedicated laundry circuit, and is already accounted for in the 3 VA/ft^2.

2) You could just use the values you found for the one dishwasher, the other is probably close. So put down (2) dishwashers, 2600 VA total

3) For HVAC equipment and other motors, the branch circuit OCPD usually doesn't provide overload protection. Its job is to provide short circuit and ground fault protection, and a separate overload protection is typically provided at the equipment/motor. So that allows the OCPD on the branch circuit to be oversized relative to the load and conductors (e.g. with 27.5A MCA and 40A MOCP, you could use #10 copper conductors and a 40A breaker, not normally allowed) Which is good, as it provides more headroom for the branch circuit OCPD not to trip from motor starting surge.

The upshot is that MCA is the spec that is closest to the actual load. If your HVAC equipment started drawing 40A for a significant period, the internal overload should trip.

4) It's up to you whether to show future loads. If you want the most EVSE current you can get now, omit them. If you don't want to have to down size the EVSE in the future, include the future loads. Certainly you wouldn't show the same load twice, once above and once in the "added load".

5) SJ errs in putting "Added Load at 100%" if it means all added loads are to be at 100%. Added loads get the same factors as existing loads. So your added loads should just be mixed in with the existing loads up above. To quote NEC 220.83(A), which has the "first 8 kVA @ 100%, rest @ 40%" rule, "The following percentages shall be used for existing and additional new loads."

Now, if you accept that SJ can unilaterally force a 100% factor for EVSEs, and your only additional loads are EVSEs, then the question is moot. But if you are adding both EVSE and non-EVSE loads, and you accept the 100% factor for EVSEs, putting the new EVSE loads on the "Added Load at 100%" line and put the rest of the new loads up above with the existing loads. You can label the loads above existing or new (or future), if you like.

Cheers, Wayne

Got it, all very helpful!

1) I will shut one of the laundry breakers, label unused, and remove it from the load calc (both branches are single receptacle, btw...just going to same room).

2) I'll do that.

3) OK, you've educated me there. And so far for 27.5A MCA, with a 30A OCPD, we've not ever had a nuisance trip. I'm not sure what gauge wire was used, though. Double check that, maybe I can go to 40A OCPD (max recommended) for additional headroom. I guess as the motor gets older, it i will draw more at both startup and sustained, right?

4) I'll leave off for now, and re-calc when we get a new dryer. Should be easy enough to re-provision the Gen3 power sharing max current at that point.

5) ok...now I get it. I accept 100% factor from SJ on the EVSE's, but yes, it seems overly conservative to treat the 30A*240V=7,200W at 100%, especially if we arent even going to use it for now . I'll see what SJ City thinks...maybe they will be OK if I move the 7,200W to the above section, so it's treated at 40%...and maybe they'll let me use it at 5,000W per the note 3.

Thanks for all your help!

 

[wwhitney]

3) No point in doing that unless the 30A breaker starts tripping

5) I thought you were leaving the future dryer off per point 4? Not following. Certainly electric dryers are rarely 7200 VA and can be entered as 5000 VA without much thought.

Cheers, Wayne

 

[YRide]

3) No point in doing that unless the 30A breaker starts tripping

5) I thought you were leaving the future dryer off per point 4? Not following. Certainly electric dryers are rarely 7200 VA and can be entered as 5000 VA without much thought.

Cheers, Wayne

So for the new dryer (electric), correct, not going to get anytime soon. But we are installing the circuit now. My interpretation is that if I am adding a new circuit, I need to add it to the "new load" calc (have inquired with SJ if I can add this at 40% or I must use 100%).

Do you think I can do similar to the #1, turn off the the breaker on the new circuit, label it "not for use", and actually not use it...and then just remove it entirely from the load calc?

 

[wwhitney]

No, if you're installing the circuit now, I'd say you should include the dryer in the load calc at 5000 VA. Wayne

 

[comanchepilot]

By way of real world example - we lived in a house with a 100 amp supply. And when we charged my wife's Tesla on a constant 40a charging circuit using a wall connector and 50amp breaker for AC [which only drew 28 amps at 16 seer when starting] and all of the other household loads we NEVER blew the main breaker. The transitory starting loads are not enough to blow the breakers usually.

I just was careful about WHEN we used other high load appliances- never using an electric dryer at night when the car was charging etc.

 

[holeydonut]

@YRide , do you really want to use both EVSE's at their maximum 48A potential each concurrently?

Gen 3 chargers allow the installer to put multiple EVSE on a single circuit, and configure them so they balance charging across the two. This way the circuit can capped at 48A. A single EVSE could get the maximum 11.5 kW if it were the only one being used at the time. But if two EVs were charging simultaneously, they'd balance down to prevent overloading the circuit. Once one EV is charged, the other EV gets to go back to the maximum 11.5 kW L2 charge.

Seems like a much easier go-around than trying to get a new total 22.5 kW approved.

I also think this is an easier way to go about things, so when you do add PV+ESS, they can more reasonably include your EVSE circuit in the backup loads. Otherwise your installer is going to say the EVSE's would need to be put on a non-backup loads panel unless you get like 6 Powerwalls.

 

[Big Earl]

All of your calculations seem high to me. You’re listing watts for the circuit size @ 100% load, but appliances typically pull 80% of that circuit size or less.

Actual watts used by the appliances in my home:

Clothes dryer: 5,800
Dishwasher: 1,050 in heated dry mode
Water heater: 4,500 (old); 5,400 (new)

and for some typical consumption figures:

Indoor air handler: 600-1,000 watts for the blower
Air conditioning: 1,000 watts per ton of cooling capacity (varies based on unit efficiency)

 

[wwhitney]

3) For the A/C, you want to use the MCA (minimum circuit ampacity) number on the nameplate, not the MOCP (maximum overcurrent protection)

Correction: MCA is basically the sum of the loads in the unit plus an extra 25% of the largest motor; for an A/C outdoor unit that largest motor is usually the compressor and the nameplate value for it is RLA (rated load amps). For the optional load calc, you only need the sum of the loads, without the extra 25%. So you should use MCA - 25% * RLA. [For a simple unit the resulting value should be equal to RLA + FLA for the fan; if there are other loads involved, that might end up lower than MCA - 25% * RLA.]

Also, for the optional load calc, there's no 5000 VA minimum on the electric dryer, so you would use the actual nameplate rating. If you haven't picked out an electric dryer yet, 5000 VA is a reasonable guess; 24A * 240V = 5760 VA is a more conservative one. Or if you go with a heat pump dryer, the rating could be quite a bit less; the name plate on mine says "120/240V 14A 60 Hz 1300W". Certainly for that you could use 240V * 14A = 3360VA, although perhaps 1300VA would suffice, that would require a little more thought/research.

All of your calculations seem high to me. You’re listing watts for the circuit size @ 100% load, but appliances typically pull 80% of that circuit size or less.

For other than the first 8 kVA (existing) or 10 kVA (new construction), and other than the HVAC, the optional load calc applies a 40% factor after you add up all the nameplates.

Cheers, Wayne

 

[CrazyRabbit]

Use the running watts for AC. Also I doubt you have seven small appliances circuits, usually only three or four. 2 in kitchen, one in dining room, and perhaps bathroom. I THINK you only need to add up the mandatory 20 amp circuits.

Download Mike holts electrical tool box, use to check your calculations.

 

[YRide]

All of your calculations seem high to me. You’re listing watts for the circuit size @ 100% load, but appliances typically pull 80% of that circuit size or less.

Actual watts used by the appliances in my home:

Clothes dryer: 5,800
Dishwasher: 1,050 in heated dry mode
Water heater: 4,500 (old); 5,400 (new)

and for some typical consumption figures:

Indoor air handler: 600-1,000 watts for the blower
Air conditioning: 1,000 watts per ton of cooling capacity (varies based on unit efficiency)

Sure, that seems reasonable for actual usage...but i don't believe that's how you do a load calc (and least by the book).

 

[YRide]

@YRide , do you really want to use both EVSE's at their maximum 48A potential each concurrently?

Gen 3 chargers allow the installer to put multiple EVSE on a single circuit, and configure them so they balance charging across the two. This way the circuit can capped at 48A. A single EVSE could get the maximum 11.5 kW if it were the only one being used at the time. But if two EVs were charging simultaneously, they'd balance down to prevent overloading the circuit. Once one EV is charged, the other EV gets to go back to the maximum 11.5 kW L2 charge.

Seems like a much easier go-around than trying to get a new total 22.5 kW approved.

I also think this is an easier way to go about things, so when you do add PV+ESS, they can more reasonably include your EVSE circuit in the backup loads. Otherwise your installer is going to say the EVSE's would need to be put on a non-backup loads panel unless you get like 6 Powerwalls.

Hi @holeydonut yes...on occasion would like to run them concurrent at full amps. That said, even though they are on different circuits...I do have them set to power share with 92A between them (which is almost full rate). This allowed me to state 48A + 44A = 92A * 1.25 = 115A * 240V = 27,600 kVA (Watts) on the SJ optional method. That allowed me to squeak in just below 200A service threshold.

In reality one of the dishwashers and disposals almost never gets used, and we dont have any near-term plan to use the electric dryer...so I believe we have plenty of headroom.

Powersharing is pretty cool. I am actually thinking to see if I could split one of the 60A OCPD branches into two EVSE (so add a 3rd charger) and just have those powershare at 48A, and then leave the other standalone branch just set at 44A and not be powershared. Might even be able to take it up to full 48A if I never use the electric dryer.

Y

 

[YRide]

Correction: MCA is basically the sum of the loads in the unit plus an extra 25% of the largest motor; for an A/C outdoor unit that largest motor is usually the compressor and the nameplate value for it is RLA (rated load amps). For the optional load calc, you only need the sum of the loads, without the extra 25%. So you should use MCA - 25% * RLA. [For a simple unit the resulting value should be equal to RLA + FLA for the fan; if there are other loads involved, that might end up lower than MCA - 25% * RLA.]

Also, for the optional load calc, there's no 5000 VA minimum on the electric dryer, so you would use the actual nameplate rating. If you haven't picked out an electric dryer yet, 5000 VA is a reasonable guess; 24A * 240V = 5760 VA is a more conservative one. Or if you go with a heat pump dryer, the rating could be quite a bit less; the name plate on mine says "120/240V 14A 60 Hz 1300W". Certainly for that you could use 240V * 14A = 3360VA, although perhaps 1300VA would suffice, that would require a little more thought/research.


For other than the first 8 kVA (existing) or 10 kVA (new construction), and other than the HVAC, the optional load calc applies a 40% factor after you add up all the nameplates.

Cheers, Wayne

Thanks for your insight @wwhitney. You are always a repository of knowledge on this stuff! I got through the inspection fine, use the load calcs on the previous post. Went very smooth.

That said, 1) always want to be as precise as possible and 2) have a dilemma coming with my PV+ESS install that I could use both your take on, plus finding every A of reduction will help. So following up on the AC...below is my nameplate.

I used the MCA = 27.5 (rounded to 28A) on my load calc.

For your suggested approach I just calculated either:

Compressor RLA + Fan FLA = 20.8 + 1.52 = 22.3A
or MCA - 25% * RLA = 27.5 - 0.25 * 20.8 = 27.5 - 5.2 = 22.3A.

So does that mean I could get away with 22.3A for the AC load in the Optional Method? Also, now that my EVSE's are installed and permitted...am I allowed to use them in the Electrical Appliances section (@ 40%)? Or do I need to always include then in the "NEW" section? And if I am allowed to add them to the 40% section now that they are installed...do I have to rate them at the OCPD (60A) or can I leave them at 48A? See two load calcs below...

Here's a load calc with the reduced AC and 2x EVSE @ 48A in the 40% section.

Here's a load calc with the reduced AC and 2x EVSE @ 60A in the 40% section.

Feels like this is just wishful thinking...the EVSE are constant loads.

 

[wwhitney]

So does that mean I could get away with 22.3A for the AC load in the Optional Method?

Yes, 22.3A is allowed for the Optional Method.

Also, now that my EVSE's are installed and permitted...am I allowed to use them in the Electrical Appliances section (@ 40%)? Or do I need to always include then in the "NEW" section?

I took another look at the SJ form again, and the "NEW" section doesn't specify a load factor. It also doesn't have much room--I'd be inclined to include an addendum with that form that includes the new loads along with their load factors, adds them up, and then just put the total on the "NEW" slot. [Absent NEC amendments, the NEW loads would always be at 40% unless they are HVAC, which would generally be at 100%.]

See posts #2-#4 for a discussion of whether EVSEs should/need to be figured at 100% vs 40%. [I'd revise my "SJ errs" comment to just "SJ is wrong on footnotes 3 and 4."] Anyway, if you can afford the time to have the form kicked back at you, go ahead and list the EVSEs under the existing section.

As to whether to list the EVSE at its continuous rating, or 125% thereof, the answer is complicated. But for most electrical service topologies, sizing rules that require a 125% factor will come into play, and so it's simplest to just include it upfront. [The full answer starts with the clarification that the output of a service calculation isn't just "X amps" but it's "X amps, of which Y is continuous," and goes from there.]

Cheers, Wayne

 

[aks20000]

By way of real world example - we lived in a house with a 100 amp supply. And when we charged my wife's Tesla on a constant 40a charging circuit using a wall connector and 50amp breaker for AC [which only drew 28 amps at 16 seer when starting] and all of the other household loads we NEVER blew the main breaker. The transitory starting loads are not enough to blow the breakers usually.

I just was careful about WHEN we used other high load appliances- never using an electric dryer at night when the car was charging etc.

Did you pull a permit for adding the wall charger ?
I have 200 amp service , but evenly split between between a sub panel and ac loads with each getting 100 amp.
sub panel has typical loads of a 3400 sq ft home ( dryer, oven , spa but no electric cooktop or water heater ) and and I am hard time finding a legal way to add 40amp charger circuit to this panel as load calculation on the panel pushes it to 125 amp.
That's why my question that how you managed to add charger to 100 amp service that has AC too on it ?