Converting 208V single phase loads into 208V three phase

[cppoly]

Calculating demand factors for 208V single phase ranges and converting to 208V three phase service, 220.55: says "Where two or more single-phase ranges are supplied by a 3-⁠phase, 4-wire feeder or service, the total load shall be calculated on the basis of twice the maximum number connected between any two phases.

Does this formula also apply to all single phase loads (AC, heating, etc.) when doing a service calculation on a 3 phase service??

 

[kwired]

No. This is a section intended to calculate the load that includes a demand factor. HVAC almost always has no allowable demand factor and is calculated at 100% of the load. If it does have an allowable demand factor it won't be at same load diversity level used to determine cooking unit loads.

 

[cppoly]

Thanks, AC is still at 100%. I'm asking if are you supposed to use this formula to convert the total connected 208V single phase load when connected to a 208V three phase service.

For instance let's say you have fifty 208V single phase AC units totally 100,000 VA in load (just a random example). This load for the 3 phase service 208V service is simply not 100,000 VA / 3 shown in each phase is it?

 

[kwired]

Thanks, AC is still at 100%. I'm asking if are you supposed to use this formula to convert the total connected 208V single phase load when connected to a 208V three phase service.

For instance let's say you have fifty 208V single phase AC units totally 100,000 VA in load (just a random example). This load for the 3 phase service 208V service is simply not 100,000 VA / 3 shown in each phase is it?

If you have it as balanced as possible it essentially is total load in VA divided by three on each conductor. If any demand factor can apply it won't be the one for cooking equipment, they tend to cycle at much different rates and also don't tend to be in use all day long therefore completely different load diversity goes into determining what demand factor can apply to them.

 

[cppoly]

If you have it as balanced as possible it essentially is total load in VA divided by three on each conductor. If any demand factor can apply it won't be the one for cooking equipment, they tend to cycle at much different rates and also don't tend to be in use all day long therefore completely different load diversity goes into determining what demand factor can apply to them.

Awesome, thank you!