The 2026 Edition of the National Electric Code (NEC) is now published. The new edition finalizes the requirement for all RVs with 30-amp or 50-amp electrical service to install a grounding monitor interrupter (GMI).
Grounding monitor interrupters are a loss-of-ground device. Before electrical current can pass into the RV, a GMI will check the receptacle for a proper ground connection. During use, the GMI will monitor the ground connection to the RV and, if lost, will disconnect the power to the RV.
The NEC governs U.S. electrical installations and is updated every three years. Article 551 of the National Electric Code contains the electrical requirements for both RVs and RV parks and campgrounds.
The GMI requirement addresses “hot skin” conditions, which are when an RV’s metal exterior, metal frame, or other metal items become electrified. RVIA said “hot skin” is an electrical safety hazard caused by improper grounding or electrical faults.
A GMI tests the receptacle plugged into the GMI to ensure correct wiring and proper grounding. If incorrect wiring or a loss of ground connection is detected, the GMI will not permit electricity to pass through. The GMI could also disconnect power if the loss of ground occurs during operation.
RVIA said an RV’s GMI will address damage to a power cord. RVIA said damage to a power cord and the use of dog-bone adapters, causing a compromised electrical supply, are the most common reasons for the NEC requirement.
The 2026 Edition of the NEC was adopted and published in late September 2025. RVIA plans to set the 2026 adoption and enforcement 2026 dates at the next Board of Directors meeting in November.
