Calculated Res. Service comes at 603A

[ptonsparky]

A 16 unit building and you're trying to jump through hoops to find a way to eliminate 3 amps from your calculation? I would just go with 800 amps which leaves room for future expansion.

How would they expand that would not mean a new service for the additional buildings? Curious. Not meant to be argumentative.

 

[kwired]

If you go with 3- 200 amp panels and 1-100 amp panel it may save a tad bit but personally I would probably go with 4-200 amp panels. Alot cheaper than an 800 amp panel

Service equipment is likely a meter center though.

Probably comes down to deciding if one goes with two 400 amp units or a single 800 amp unit.

 

[kwired]

How would they expand that would not mean a new service for the additional buildings? Curious. Not meant to be argumentative.

I have to agree that if it is apartments the load at each dwelling isn't likely to change when it comes to NEC calculations, unless you changed something from gas to electric or added entire new apartment units.

 

[Sierrasparky]

How would they expand that would not mean a new service for the additional buildings? Curious. Not meant to be argumentative.

Greater house loads- such as EV chargers.
upgrade a individual unit. Who knows.

 

[Sierrasparky]

If you go with 3- 200 amp panels and 1-100 amp panel it may save a tad bit but personally I would probably go with 4-200 amp panels. Alot cheaper than an 800 amp panel

I don't understand that.
I usually see and do group modular metering out here on the west. Sometimes separated into 2 sections each with a main switch,tenant meters with main breaker.

 

[infinity]

I haven’t done any apartment housing of that size but I would think the loading would be consistent throughout its lifetime. 599 amp Service should be good. Future EV charging would be the changer.

How would they expand that would not mean a new service for the additional buildings? Curious. Not meant to be argumentative.

Just my opinion but you mentioned one possibility, the addition of car chargers in the future. Unless the owner asks for the absolute cheapest possible installation adding another 200 amps to the service instead of massaging the calculation seems like a better design to me. I do agree that the apartment load shouldn't really change.

 

[kwired]

Just my opinion but you mentioned one possibility, the addition of car chargers in the future. Unless the owner asks for the absolute cheapest possible installation adding another 200 amps to the service instead of massaging the calculation seems like a better design to me. I do agree that the apartment load shouldn't really change.

800 amps may not be enough to add car chargers to every unit in OP's case. This is a significant enough change to fit in with what I said earlier of changing something in each unit from gas to electric.

 

[Dennis Alwon]

Tesla's charger- or some of them- can be linked together, up to 4 units, with one 60 amp circuit. You feed into a monitoring device then out to each charger. Apparently, it will monitor how much each charger gets but will not let it go over the 60 amp limit...

 

[kwired]

Tesla's charger- or some of them- can be linked together, up to 4 units, with one 60 amp circuit. You feed into a monitoring device then out to each charger. Apparently, it will monitor how much each charger gets but will not let it go over the 60 amp limit...

Can that work when each charger is on separate tenant metering? If all the chargers are later installed on a "house panel" then it would just be simpler to run a separate "house service" later on if more service capacity is needed.

 

[ramsy]

310.15.(B)(7) Only applies to the supply conductors (feeder or service) to an individual dwelling unit.

Getting a visual on this now. Thank You.

Please disregard applying 310.15(B)(7) beyond individual-unit feeds, much less where multi-unit demand factors are used.

And in this case it can't be used for the individual dwellings since the supply voltage is 208/120.

While 2017 NEC may include 208Y/120v feeds, I now see the 83% can only apply to an individual-unit feed.