Load Calculation Feeders And Services
Level 4 Module 1
What is the demand factor allowed by the NEC® for calculating the neutral conductor
size for electric range load? - ANSWER- 70%
Using the VA/linear foot method, the total VA that must be used in a service calculation
for a 50' show window is - ANSWER- 12,500VA
Before it is considered a continuous load, a load must operate for at least how many
hours without interruption? - ANSWER- 3
Which of the following factors does not affect conductor ampacity adjustments? -
ANSWER- Number of phase
If a continuous connected load totals 120A, what is the minimum current-carrying
capacity required for the feeder? - ANSWER- 150A
What is the load center length for a tapped feeder with loads of 120A at 50', 110A at 60',
75A at 90', and 70A at 150'? - ANSWER- 79.60
Which of the following lighting loads would be used in a residence that is 1,650 sq ft? -
ANSWER- 4,950VA
What is the load for 40 non-dwelling unit receptacles? (Assume that the load is not
continuous.) - ANSWER- 7,200VA
The minimum service rating for a residential service is - ANSWER- 100A
Residential small appliance circuit must be rated at - ANSWER- 1,500VA
Use of the 100' tap rule is limited to installation in high-bay manufacturing buildings with
wall heignt over - ANSWER- 35 feet
Which part of a residential lighting and small appliance load must be rated at 35% for
service calculations? - ANSWER- The next 177,000VA
If a store lighting load is 14,000VA (continuous), which of the following must be used for
the circuit calculation? - ANSWER- 17,500VA
In most cases, feeder conductor size is adjusted when - ANSWER- there are more than
three current-carrying conductors in the raceway
When calculating the service requirement for a particular building, the step is to -
ANSWER- determine the floor area of the building
Level 4 Module 1
What is the demand factor allowed by the NEC® for calculating the neutral conductor
size for electric range load? - ANSWER- 70%
Using the VA/linear foot method, the total VA that must be used in a service calculation
for a 50' show window is - ANSWER- 12,500VA
Before it is considered a continuous load, a load must operate for at least how many
hours without interruption? - ANSWER- 3
Which of the following factors does not affect conductor ampacity adjustments? -
ANSWER- Number of phase
If a continuous connected load totals 120A, what is the minimum current-carrying
capacity required for the feeder? - ANSWER- 150A
What is the load center length for a tapped feeder with loads of 120A at 50', 110A at 60',
75A at 90', and 70A at 150'? - ANSWER- 79.60
Which of the following lighting loads would be used in a residence that is 1,650 sq ft? -
ANSWER- 4,950VA
What is the load for 40 non-dwelling unit receptacles? (Assume that the load is not
continuous.) - ANSWER- 7,200VA
The minimum service rating for a residential service is - ANSWER- 100A
Residential small appliance circuit must be rated at - ANSWER- 1,500VA
Use of the 100' tap rule is limited to installation in high-bay manufacturing buildings with
wall heignt over - ANSWER- 35 feet
Which part of a residential lighting and small appliance load must be rated at 35% for
service calculations? - ANSWER- The next 177,000VA
If a store lighting load is 14,000VA (continuous), which of the following must be used for
the circuit calculation? - ANSWER- 17,500VA
In most cases, feeder conductor size is adjusted when - ANSWER- there are more than
three current-carrying conductors in the raceway
When calculating the service requirement for a particular building, the step is to -
ANSWER- determine the floor area of the building
