bduda
Member
- Location
- Pennsylvania
We are working on a project where sixteen modular units will be joined together to form a temporary bus terminal. Each of the sixteen units will have it's own subpanel (most are 125 AMP)that feeds HVAC electric heating/cooling package units along with the normal lighting and receptacle circuits. There will be a main distribution panel set up to feed these subpanels. Service is 120/240 single phase.
These units are being supplied design/build and I am reviewing the calculations to begin coordination with the local power company. The loads for the HVAC units (10,560 watts per phase) are making up about 40% of the total load resulting in a large service size.
The modular manufacturer indicates that they do not endorse or suggest the use of any demand factor reductions and that they would be at the direction of the contractor. They further go on to admit that properly factored, they could substantially reduce the building service requirements. It seems highly unlikely that all sixteen HVAC units would ever run at once. What, if any, demand factor reduction factors could be applied to these HVAC units? They'll do a receptacle demand reduction per 220-13 but thats nothing compared to the HVAC demand.
Any insight or recommendations from someone who has dealt with this type of installation would be helpful.
Bradley G. Duda, P.E.
These units are being supplied design/build and I am reviewing the calculations to begin coordination with the local power company. The loads for the HVAC units (10,560 watts per phase) are making up about 40% of the total load resulting in a large service size.
The modular manufacturer indicates that they do not endorse or suggest the use of any demand factor reductions and that they would be at the direction of the contractor. They further go on to admit that properly factored, they could substantially reduce the building service requirements. It seems highly unlikely that all sixteen HVAC units would ever run at once. What, if any, demand factor reduction factors could be applied to these HVAC units? They'll do a receptacle demand reduction per 220-13 but thats nothing compared to the HVAC demand.
Any insight or recommendations from someone who has dealt with this type of installation would be helpful.
Bradley G. Duda, P.E.