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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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)
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