CME Advanced Load Calculations 3

Question 1

When applying demand factors to a 50-unit apartment building's general lighting load per NEC Table 220.42, what demand factor applies to the portion of load from 120,001 VA and above?

Accepted Answer

35%

Answer

NEC Table 220.42 applies 35% demand factor to the remainder of the lighting load above 120,000 VA in dwelling units.

Question 2

A 200A, 240V single-phase service feeds a dwelling. Using NEC 220.82 optional method, the first 10 kVA of total connected load is counted at what percentage?

Accepted Answer

100%

Answer

Under NEC 220.82 optional method, the first 10 kVA of all connected load is counted at 100%.

Question 3

A commercial kitchen has five 5 kW commercial cooking units. Per NEC Table 220.56, what demand factor applies?

Accepted Answer

70%

Answer

NEC Table 220.56 for 5 cooking units in commercial occupancies applies a 70% demand factor.

Question 4

Per NEC 220.87, when determining the existing load on a service being upgraded, the maximum demand data must cover a minimum period of:

Accepted Answer

30 days

Answer

NEC 220.87 requires that maximum demand data be based on a minimum 30-day period to determine existing load.

Question 5

For a 240V, 1-phase, 10 kW fixed electric space heater, what is the minimum circuit ampacity required per NEC 424.3(B)?

Accepted Answer

52.08 A

Answer

Fixed electric space heaters are considered continuous loads; 10,000 W / 240 V = 41.67 A × 125% = 52.08 A minimum ampacity.

(CME) Certified Master Electrician Practice Test

(CME) Certified Master Electrician Practice Test

CME Advanced Load Calculations 3