Residential load calculation

Status
Not open for further replies.

nizak

Senior Member
Where do the following loads fit into a residential load calculation?

- Hot tub... 100% nameplate?
- EV charger 100% nameplate?
- In ground pool equipment ?
Depending on how these are treated in the load calc these three items are usually the difference between a 200 amp and a 400 amp service.
I don't want to undersized the service and I don't want to install something not needed.

It used to be we could just get a 320/400 meter base and the POCO would hook it up no questions asked at the same cost as a 200amp.
Now it's a lengthy process and an expensive one to have the 400 amp approved and installed.

Thanks
 
I don't mean to steal this thread!
If an Average household has all these things minus the EV charger than adding a EV charger ain't going in ?

Granted I thought the average EV charger was either a 40 or 60 Amp?
 
Last edited:
What I mean is if they have a pool and a hot tub, one is going to have to do a load calc to qualify the install of a
40 through 60 AMP breaker?

What I'll assume is that most of these are either mini mcmansions maxi-loaded or already at split 400 amps
IE 2- 200 amps and that will be no problem.

If it's only 200 Amp service, a load Calc. will be required to safety install EV service?
 
Thanks, I've never touched one, I believe there's more 125, 150 and 200 service's out there than split 400's.
Have at it boys and girls...
 
EV Charger (EVSE, actually) is a continuous load and should be calculated at 125%, I believe.
For the branch circuit I see that in 625.
I did not see anything in 220 that address specifically EV for load calc.
625 does not address load calc either..
Don't do Ev alot, looks like the rapid ones can charge in under an hour so they would not qualify as continuous load since I don't see them stated in 220.
Any charge that is 3 or longer would be continuous.
ev-charging-speeds-explained-slow-fast-and-rapid
That was a click and grab link it could be wrong on the rapid time.

Though I guess if its a rapid charge the amps must be huge compared to the slow. Either way for your load calc it depends on what charge I would assume, if that is none.
 
The linked article wasn't great. It may be referencing european chargers because the amps don't seem right for the KW. Rapid chargers that charge a car from near dead to 85% in an hour are 50KW to 100 KW in size. You won't be putting one of those in a residence. A level 2 charger is typically 32 to 48 amps (40 to 60A circuit at 240V). These can take 5 to 10 hours to charge a car. Charge time depends on how big the battery is and how dead it is. The level 1 chargers are 12A or 16A at 120V. These can take a long time to charge, but everyone has a 15 or 20 amp receptacle.

The Optional calculation says to use nameplate values and mentions nothing about continuous loads. It doesn't take long in that calc to get over 10KW which means anything after that which is general purpose will have a 0.4 factor applied to its nameplate.
 
So after several posts is it safe to assume the car charger and hot tub should be figured at the nameplate for both if doing a standard calculation?100% for each?
 
they would fall under 220.53 in my mind so 75% of name plate after 3 appliances, they meet the article 100 definition of appliance.
Why you standard,Optional is usually always a lower service.
the motor load In the tub is accounted for in the nameplate.
 
Status
Not open for further replies.
Top