340 Electrical Power Systems Technology
Table 13-3. Building Lighting Requirements
in Wattage per Square Foot
—————————————————————————
Type of Building Watts
Armories and Auditoriums 1
Banks 2
Churches 1
Dwellings (other than hotels) 3
Garages (for commercial storage) 1/2
Hospitals 2
Hotels and Motels 2
Industrial or Commercial Buildings 2
Office Buildings 5
Restaurants 2
Schools 3
Stores (grocery) 3
Warehouses (storage) 1/4
—————————————————————————
Sample Problem:
Given: a room in a commercial building is 70 feet × 120 feet (21.34
× 36.58 meters). It will use 125 fluorescent lighting units that draw 3 am-
peres each. Also, 20-ampere branch circuits will be used. The power factor
of the units is 0.75. The operating voltage is 120 volts.
Figure 13-11. Pictorial view of the circuit of Figure 13-10 (A)