National Electrical Code Articles and Information

National Electrical Code Top Ten Tips: Article 552 -- Park Trailers

1. Article 552 covers the electrical equipment and conductors (for park trailers) not already covered by Article 550 or 551 [550.1]
   
   
2. A park trailer is not a permanent dwelling, nor is it intended for commercial use. It is intended for seasonal use [552.4].
    
3. Splices must be made in a particular way; one aspect is they must be mechanically and electrically secure (as is not the case when soldering together two wires that are not first mechanically joined) [552.10(C)(2)].
    
4. You must separate the power wiring from all other wiring [552.10(C)(3)].
    
5. For low voltage overcurrent protection, rate your overcurrent devices per Table552.10(E)(1)].
    
6. Locate the overcurrent protection devices in an accessible location within 18 inches of where the trailer power supply connects to its circuits [552.10(E)(4)].
    
7. If you use a voltage converter to supply 120V, the wiring of the unit must comply with the requirements of Parts I and IV of Article 552 [552.20(B)].
    
8. The rule above also applies if you connect to a nominal 120V/240V source, but in addition it must comply with Parts III and V of Article 552 [552.40].
    
9. The distribution panelboard must have an equipment grounding (bonding) terminal [552.45(A)].
    
10. The requirements for branch circuit determination are detailed, and should be reviewed prior to final approval of any wiring design. You'll find those in 552.46.