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Power Density - Single or Three Phase?

Hello all,


Quick question regarding initial load assessments using power densities.


Keeping my numbers simple, lets say we take a small power density of 20W/m2, over a GIA of 1000m2, this gives a max demand of 20kW. Now i have always taken this to be a single phase load, and so if the space is being served via a three phase power supply, would it be correct to split this 20kW across the three phases (assuming perfect balance across phases). i.e. the small power maximum demand for the space would be 6.7kW.


Any help would be appreciated.


Thanks in advance,


Simon.


Parents
  • Power is usually quoted as a total, unlike current which is usually per phase. So 20kW could be (approx) 87A single phase or 29A per phase 3-phase (or even 44.5A per phase split phase) - as you say presuming you can achieve an equal split between phases. (Often that's not entirely convenient and you end up with not quite an even split - but it should total up the same).

      - Andy.
Reply
  • Power is usually quoted as a total, unlike current which is usually per phase. So 20kW could be (approx) 87A single phase or 29A per phase 3-phase (or even 44.5A per phase split phase) - as you say presuming you can achieve an equal split between phases. (Often that's not entirely convenient and you end up with not quite an even split - but it should total up the same).

      - Andy.
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