United States
Hong KongElectrical Systems
Three of 115 scored questions, the smallest category, covering temporary power, grounding and GFCI protection, and service and distribution coordination with other trades.
Three questions. The smallest category on the paper, and worth exactly as much per question as any other.
The two subtopics
- Temporary power, grounding and GFCI protection
- Service, distribution and coordination with other trades
What a general contractor is asked
Site safety and coordination, not electrical design. You are not expected to size a service.
What you are expected to know is what makes a site safe and where your responsibility sits relative to the electrical subcontractor's.
GFCI on temporary power
Ground fault circuit interrupter protection, or an assured equipment grounding conductor program, is required for temporary power on construction sites under 29 CFR 1926.404(b)(1).
Note the alternative. It is not GFCI or nothing - the assured grounding program is a permitted substitute, and questions test whether you know a second option exists.
10 feet minimum from energized lines up to 50 kilovolts for general work, and 20 feet as the default during crane assembly under Subpart CC. Two different numbers for two different activities, both in the OSHA standards.
Lockout and tagging
Required before work on de-energized equipment, at 29 CFR 1926.417. The principle is that de-energized is not the same as safe until it is locked out and verified.
How much to prepare
Lightly. Three questions does not justify heavy tabbing, and the material overlaps with General Requirements anyway. Know where in the OSHA standards to look.
Common questions
How many electrical questions are on the NASCLA exam?
3 of the 115 scored questions, the smallest category.
What is required for temporary power?
GFCI protection or an assured equipment grounding conductor program, under 29 CFR 1926.404(b)(1).
What clearance is required from power lines?
10 feet minimum for lines up to 50 kilovolts for general work, and 20 feet as the default during crane assembly.
What does lockout require?
Locking and tagging circuits before work on de-energized equipment, under 29 CFR 1926.417.
How much should I study this category?
Lightly. Three questions, and the material overlaps with General Requirements.