Panel Load Calculations

porschedude996T

How does one calculate the load for either an existing panel and a new panel? I am weighing my options on weather to upgrade from a 100amp panel to a 125, 175, or a 200amp panel.

Bondo

Ayuh,.....

Basically,......

Add up the Total Load that would ever be required,......
And,....
Go with a Larger entrance.......

With My Own buildings,......
I just put in a 200amp,+ use whatever I need......
Once past the initail cost,...
It doesn't matter if I'm using 10amps or 199amps,.....
Everything Works.....

moneymgmt

I agree with Bondo, an upgrade is costly as it is and I can't imagine much of a difference between upgrading 25amps or 100amps..... they both require new panel, new wire, re-wiring. If you really need an upgrade, just shoot for the 200amp service so you're not back in this spot in 2 years with the next project that comes along and requires more power.

Stubbie

Your going to find that anything between 100 and 200 amps for residential is normally not done. The local codes and power companies normally require upgrade from 100 amps or less to 200 amps or 400 amps depending on the upgrade load calculation for the dwelling. I suppose you could choose to install a panel of less amperage of your choice but that would be rather illogical with a 200 amp service brought to the house by the power company. In fact finding a 150 amp or 175 amp panel will be a bit of a challenge.

To do a load calculation on your dwelling requires some simple math and always considers load diversification. There are two options laid out in article 220 of the NEC the standard load calculation and the optional load calculation. These links are two very good sources......


http://ecmweb.com/mag/electric_dwell...feederservice/

http://www.selfhelpandmore.com/homew...calc/index.htm

Andy in ATL

Hey Stubbie. Atlanta is awash with 150A panels. In many production homes, standard is 150 or the buyer can upgrade to 200A. Your typical custom goes 200, 300, 400 and up.

Stubbie

What I'm saying is the power companies do not upgrade to 150 amp services or 175 amp services to dwellings they upgrade to 200 amps or 400 or more. What you hang as a builder or electrician is another story. You can find 150 amp panels but its been awhile since I have seen one anywhere but the supply house. I did see one at the hardware the other day.

porschedude996T

Thanks Stubbie for the information. It may be a little different out here in California. I disagree with you on what the power company wants to upgrade. My power company (PG&E) will pull any conductor I request within reason. It of course needs to match the panel I install. I have a 100amp service at present, feed by 1/0 Alu. The PoCo said that I could use the existing feed for a 125amp upgrage and they will pull any size conductor thru a 4" conduit that I need to provide if I want something higher.

The latest on my upgrade is as follows: I wish to have a 200amp service but I don't want to tear-up the whole driveway to trench 55' at 27" deep to install a new 4" conduit. I wanted to have them pull 2/0 copper thru my existing 2" conduit, but my power company doesn't work with copper. So the rep said that I could install a new vault next to the existing and divert the existing conduit to the new vault and pull my own copper to my new vault. I would provide a 4" conduit from the old vault to the new vault and they would pull 3' of 4/0 Alu conductors and connect to my 2/0 copper. I then would be responsible for the 55' run to my meter.

I think this is the least disruptive and the least expensive too.

Stubbie

Well that's what I get for thinking all states are the same, around here you are required on upgrades to go to 200 amps minimum there are some exceptions like mobile home parks.