3 phase, sufficient power?

[zixus]

Hi, I’m not the best when it comes to electricity so correct me if I’m wrong but here's my scenario. I need to power 1000 500watt devices at the normal 120volts. So I should need 500Kwatts. The building I am in has 2 main lines, both are 100amp 3phase. From my understanding this is tapped at 6 places, or 3 per line, to get 6 100amp 120volt lines out of it. Mathematically I see this as only 72Kwatts which is only enough for about 144 devices.

The person owning the building claimed 2000 250watt devices would run off what the building has, but unless those hundred amp lines can run in parallel or something I’m not thinking of, I don't think it's possible. The building also has over 90 15amp circuits as well, which is over 162Kwatts. So I'm officially confused as to what or who’s is right. Could someone tell me if this is sufficient power or if I’m coming at this from the wrong perspective? Thanks

 

[dpc]

Watts are watts. What is the voltage of the incoming three-phase service?

 

[zixus]

the owner said 120volts

 

[waross]

Your calculations look OK to me. There may be something about the system that you don't know or havn't been told. Or the owner may be mistaken.
yours

 

[jraef]

As dpc asked, what it the incoming voltage? 120V 3 phase does not exist. It may possibly be 208V 3-phase which gives you 120V phase to neutral. But you can't legally tap off 6 x 100A sub panels from a single 100A service drop, so something is not computing here. You are mistinterpreting something, or you don't have the entire picture.

Eng-Tips: Help for your job, not for your homework Read faq731-376

 

[Senselessticker]

You need to get someone with an electrical background to interface with the building owner. Especially if the owner of the building does not have an electrical background. I agree with the others, something is not adding up. Folks here could probably help, but we would need much more detailed info. 500kW is "ALOT" of Watts. Something esle to consider is if these devices actually operate at 250Watts. For instance: computers / networking equipement, etc...usually draws much much much less current/power than indicated on the nameplate.

 

[zixus]

thanks for the input, i will be getting back with the owner, and i may have someone that can talk specifically about the owner about the power.