If the load is continuous you multiply the LOAD by 1.25...not the source.
So if your 37 Amp tanning beds are continuous you need to treat them as (37x1.25)=46.25 Amp loads.
If you'd rather move the calculation to the transformer you would multiply the transformer rating by the inverse of 1.25 (which is 0.8).
That means that you would treat your 208Amp transformer output as a source that is capable of supplying (208x0.8)=166.4 Amps.
Since it is rare that a transformer feeds ONLY continuous loads pretty much nobody uses the 0.8 method...it's just a thumbnail shortcut.
Last edited by ghost307; 09/29/17 09:43 AM. Reason: typo
