NEC 720: Circuits and Equipment Operating at Less Than 50 Volts
What This Article Covers
NEC Article 720 covers installations operating at less than 50 volts — landscape lighting, doorbells, intercoms, and similar low-voltage systems that are not power-limited and not covered by other low-voltage articles.
Key Requirements
- Conductors not smaller than 12 AWG copper
- Lamps in fixtures must be rated for the supply voltage
- Receptacle outlets shall be rated for the system voltage
- Equipment grounding conductors required as in higher-voltage systems
- Overcurrent protection per 240
Common Field Applications
- Landscape lighting transformer secondary
- Battery-powered emergency lighting
- Industrial 24/48 VDC control circuits
Common Mistakes & Inspection Failures
- Using 18 AWG bell wire on a 720 circuit (must be 12 AWG min)
- Skipping equipment grounding
- Confusing 720 with 725 (power-limited / Class 2)
Related NEC Articles
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Frequently Asked Questions
What does NEC 720 cover?
NEC Article 720 covers installations operating at less than 50 volts — landscape lighting, doorbells, intercoms, and similar low-voltage systems that are not power-limited and not covered by other low-voltage articles.
What are the key requirements of NEC 720?
Key requirements include: Conductors not smaller than 12 AWG copper; Lamps in fixtures must be rated for the supply voltage; Receptacle outlets shall be rated for the system voltage. See the full requirements list on this page.
What are common mistakes with NEC 720?
Using 18 AWG bell wire on a 720 circuit (must be 12 AWG min) Skipping equipment grounding Confusing 720 with 725 (power-limited / Class 2)
Related Resources
Michael Briglio
IBEW Local 134 Journeyman · Licensed Contractor · IL Educator
Michael started in the IBEW at 18 and made foreman as a 3rd-year apprentice. Thirteen years in, he’s a Local 134 journeyman, a licensed electrical contractor, a licensed Illinois teacher, and OSHA 30 and EPA 608 certified. He teaches a federally recognized pre-apprenticeship on the south side of Chicago — where he’s helped 100+ students get into the IBEW. He built Sparky AI around exactly what the NJATC exam tests and what trips people up. Prep with this and you walk in ready.
Facts on this page trace to primary sources or first-hand IBEW Local 134 experience — see sources & methodology.