Special Occupancies: Mobile Homes (550), Recreational Vehicle Parks (551) and Marinas/Docking Facilities (555)
Three Chapter 5 articles the Texas outline groups under "special occupancies" that share one idea: the structure is a plug-in load — a mobile home feeder assembly, an RV site pedestal, a shore-power receptacle — so the Code fixes the receptacle configurations, the demand factors, the mounting heights and the ground-fault protection. 2026 note: the demand tables moved out of these articles into Article 120 — RV parks use 120.130 (was 551.73) and marina shore power uses 120.120 (was Table 555.6). Written from the 2026 text.
NFPA 70 National Electrical Code, 2026 edition · Reviewed 2026-09-19
Three Chapter 5 articles the Texas outline groups under "special occupancies" that share one idea: the structure is a plug-in load — a mobile home feeder assembly, an RV site pedestal, a shore-power receptacle — so the Code fixes the receptacle configurations, the demand factors, the mounting heights and the ground-fault protection. 2026 note: the demand tables moved out of these articles into Article 120 — RV parks use 120.130 (was 551.73) and marina shore power uses 120.120 (was Table 555.6). Written from the 2026 text.
1. Mobile and manufactured homes — Article 550
- 550.10 power supply: not more than one listed 50 A mobile home power-supply cord (40 A permitted where the home is factory-equipped with gas or oil central heating and cooking), or a permanently installed feeder. The feeder assembly is permanently attached to the panelboard (or a junction box tied to it), has four conductors (one green or green/yellow EGC), a strain-relief clamp at the panel knockout, and terminates in a 3-pole, 4-wire grounding-type attachment plug cap rated 50 A, 125/250 V (Figure 550.10(C)); a right-angle cap is oriented with the grounding member farthest from the cord. No adapters, pigtails or extension cords ship with the home.
- 550.50 distribution system: the park secondary system to mobile home lots is single-phase 120/240 V.
- 550.51 service equipment: not mounted in or on the mobile home; within sight of the home it serves; rated not less than 100 A at 120/240 V with provisions for connecting the feeder assembly by a permanent wiring method; power outlets used as service equipment may hold receptacles up to 50 A (50 A ones per Figure 550.10(C)); a means for a fixed-wiring connection to an accessory building or outside equipment; receptacles on the outside of the service equipment GFCI-protected per 210.8(A) except the home's own supply receptacle; the disconnect is mounted with the bottom of the enclosure ≥ 2 ft above grade and the handle grip center ≤ 6 ft 7 in.; where a 125/250 V receptacle is used the marking "TURN DISCONNECTING SWITCH OR CIRCUIT BREAKER OFF BEFORE INSERT
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