LLC Landscape Lighting Safety & Code Compliance 2 — Questions and Answers
Question 1: Which NEC article specifically governs the installation of outdoor landscape lighting systems?
- Article 300
- Article 410
- Article 411 (Correct answer)
- Article 680
Correct answer: Article 411
NEC Article 411 covers lighting systems operating at 30 volts or less, which applies to most low-voltage landscape lighting.
Question 2: What is the maximum voltage permitted for low-voltage landscape lighting circuits under NEC Article 411?
- 12 volts
- 24 volts
- 30 volts (Correct answer)
- 50 volts
Correct answer: 30 volts
NEC Article 411 defines low-voltage lighting systems as those operating at 30 volts or less between conductors.
Question 3: A landscape lighting transformer must be Listed and marked with its rated output. What additional marking is required for line-voltage transformers used outdoors?
- 'Outdoor Use Only'
- 'Weatherproof'
- 'Suitable for Wet Locations' (Correct answer)
- 'GFCI Protected'
Correct answer: 'Suitable for Wet Locations'
Transformers installed in outdoor locations must be Listed and marked as suitable for wet locations per NEC requirements.
Question 4: When installing landscape lighting near a swimming pool, which NEC article takes precedence for bonding and grounding requirements?
- Article 250
- Article 411
- Article 680 (Correct answer)
- Article 700
Correct answer: Article 680
NEC Article 680 governs all electrical installations in and around swimming pools and takes precedence over Article 411 in those areas.
Question 5: What minimum burial depth is required for rigid metal conduit (RMC) installed for landscape lighting under a residential driveway?
- 6 inches
- 12 inches (Correct answer)
- 18 inches
- 24 inches
Correct answer: 12 inches
RMC requires only 6 inches of burial depth under driveways for residential use, but standard open ground depth is 6 inches for RMC.
Question 6: A GFCI device protecting outdoor landscape lighting must trip within what maximum time when a ground fault of 5 mA occurs?
- 0.025 seconds (Correct answer)
- 0.1 seconds
- 1 second
- 5 seconds
Correct answer: 0.025 seconds
Per UL 943, Class A GFCIs must trip within 0.025 seconds (25 milliseconds) when a fault of 6 mA or more is detected.
Question 7: Which condition requires a weatherproof 'in-use' cover (bubble cover) rather than a standard weatherproof cover for an outdoor receptacle serving landscape lighting?
- When the cord is permanently connected
- When a plug is inserted during rain or snow (Correct answer)
- When the receptacle is above 6 feet in height
- When more than one circuit feeds the receptacle
Correct answer: When a plug is inserted during rain or snow
In-use covers are required where a cord and plug connection will remain inserted while the unit is in use and exposed to weather.
LLC Landscape Lighting Safety & Code Compliance 2
Which NEC article specifically governs the installation of outdoor landscape lighting systems?