Question 2044 of 749 · Maryland Journeyperson Electrician Exam
A 480Y/277 volt switchboard faces a concrete wall (Condition 2). What is the minimum depth of the working space?
Exactly one answer is correct.
You got of questions right. Here on the question pages nobody remembers which ones you got wrong. The trainer saves your progress and asks the mistakes again until they stick.
Or free: the 10 questions most people get wrong
Show solution
Correct answer to question 2044
- B: 3 ft 6 in.
Explanation
A 480Y/277 volt system is 277 volts to ground, where the depth is 3 ft for Condition 1, 3 ft 6 in. for Condition 2 and 4 ft for Condition 3. Concrete is considered grounded, which makes this Condition 2. See Table 110.26(A)(1).
More questions: Services and Service Equipment
- 2045Overhead service conductors operating at more than 300 volts to ground pass over a residential driveway. What is the minimum vertical clearance?
- 2046Which edition of the NEC first required an outdoor emergency disconnect for one- and two-family dwelling services?
- 2047Which of the following is permitted to be connected on the supply side of the service disconnecting means?
- 2048Which situation permits an additional service to a building?
- 2049Using the 83 percent rule of the 2020 and 2023 NEC, what minimum copper THWN conductor at 75 degrees C is needed for a 200 A, 120/240 volt one-family dwelling service?
- 2050A service drop cable with a bare messenger operates at 120/240 volts. What is the minimum clearance above a sidewalk accessible only to pedestrians?