For a retail store building with dimensions of 100 feet by 75 feet. • Service is 208Y/120-volts, 3-phase, 4-wire • Actual connected general lighting load of 14,000 VA • The store has 50 continuous feet of show window lighting. • The building is provided with 115 general use-receptacle outlets • Fifty (50) feet of multioutlet assembly where the cord-connected appliances are likely to be used simultaneously will be installed. • Forty (40) feet of track lighting will be installed for accent lighting. • The store will have two (2) 20-ampere, 120-volt exterior electric sign circuits. • Consider all overcurrent protection devices not to be listed for continuous use. When calculating the service for the building, what required VA must be included for the general lighting load?
220.12 Table 220.12 100 ft. x 75 ft. = 7,500 sq. ft. x 1.9 VA = 13,680 VA
Given the following information, what is the maximum approximate distance a single-phase, 240-volt, 42 ampere load can be located from a panelboard? * copper conductors – K = 12.9 * size 8 AWG THWN/THHN conductors are used * Limit voltage drop to 3%
2020 National Electrical Code Chapter 9 Tables Table 8:Conductor Properties Notes: …
Where K=12.9, what is the approximate voltage-drop on a circuit where an 80-ampere, 240-volt, single-phase load is supplied with size 3 AWG copper conductors with THWN insulation, and placed 200 feet from a panelboard?
2020 National Electrical Code Chapter 9 Tables Table 8: Conductor Properties Notes: 1. These resistance values are valid only for the parameters as given. Using conductors having coated strands, different stranding type,…
The maximum allowable ampacity for No. 2/0 copper conductors of type THHN, 167°F rated insulation, with 2 current-carrying conductors in the cable, installed in an ambient temperature of 30°C is:
Ampacities for conductors rated 0 to 2000 volts shall be as specified in the Allowable Ampacity Table 310.15(B)(16) through Table 310.15(B)(19), and Ampacity Table 310.15(B)(20) and Table 310.15(B)(21) as modified…
Pipe electrodes shall have resistance to ground not to exceed ___________ ohms when used alone.
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