calculating the branch circuit loads for a computer lab

[4thwave]

When calculating the branch circuit loads for a computer lab ( 30 desk tops in one classroom ) Is it a requirement to use 125% of "nameplate rating"?

And which article refer to the use of the "nameplate rating"? Thanks

 

[suemarkp]

Not sure you'll find a definitive answer, but I think you'll find most computers rarely if ever draw their nameplate rating. Even though they tend to run for 3 hours or more, their load varies with use. So I would not apply a continuous load factor. Generally, I use about 50% of the naemplate when calculating feeders and branch circuit loading. But the best way to know the true load of the computer is to measure it while it is processing a graphics intensive application. A computer stuffed with the max RAM, disk, and high end graphics card may actually draw near its nameplate rating under heavy use.