Selecting, sizing transformers for commercial buildings While
commercial building designs change, their electrical loads
remain fundamentally unchanged. Properly sizing and selecting
transformers ensures that these loads are accommodated. By Ralph
Baeza, PE, LEED AP, TLC Engineering for Architecture, Miami
Transformers, along with other power distribution apparatus,
remain a fundamental component in electrical systems
distribution for commercial buildings. This article presents
several useful design concepts for selecting and sizing
transformers in the design of electrical systems for commercial
buildings. Transformers change voltage levels to supply
electrical loads with the voltages they require. They supply the
required incoming electrical service to the buildings.
Transformer primary and secondary voltages can be 2,400; 4,160;
7,200; 12,470; and 13,200 for 15-kV Class, and 120, 208, 240,
277, and 480 for 600-V Class. Transformers are located either
outdoors or inside buildings in an electrical room or oth