OBJECTIVE 108.3 WORKSHEET 1. What is the maximum number of recessed luminaires that can be installed on a 20-amp 277-volt branch circuit? Each luminaire will draw 36.8 watts at 277 volts. These luminaires will NOT be operated continuously. DO NOT multiply anything times 1.25!!! DO NOT divide anything by .8!!! a. 120 b. 65 c. 188 d. 52 e. 150 2. How many 2-by-4 lay-in luminaires can be installed on a 20-amp circuit? Each luminaire will draw 128 watts at 120 volts. These luminaires will NOT operate continuously. DO NOT multiply anything times 1.25!!! DO NOT divide anything by .8!!! a. 19 b. 43 c. 29 d. 44 e. 18 3. A grocery store is to have 32 fluorescent luminaires installed on the ceiling. Each of these luminaires will use 180 watts of power at 120 volts. You will need to install at least ___ 15-amp lighting circuits to supply these luminaires. This store is open from 5 a.m. to midnight so the lighting is "ON" continuously. a. 1 b. 4 c. 5 d. 3 e. 2 4. What is the minimum number of 20-amp 277-volt branch circuits required where 810 incandescent luminaires are to be installed? The lamps to be installed are rated at 75 watts at 277 volts. This is NOT a continuous load so each circuit can carry 20 amps maximum. a. 11 b. 41 c. 59 d. 73 e. 51
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The maximum number of recessed luminaires that can be installed on a 20-amp 277-volt branch circuit can be calculated by dividing the total power of the circuit (20 amps * 277 volts = 5540 watts) by the power of each luminaire (36.8 watts). So, 5540 / 36.8 = Show more…
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