550.51 Mobile home surge protection
What changed in 550.51
A surge protective device is now required when a new mobile or manufactured home replaces an old one on an existing service.
Point by point
- New 550.51(E): when an existing service is hooked up to a new replacement home, a surge protective device per 230.67 is required.
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Get the whole breakdown
- 3 more points on exactly what changed
- The 2023 rule next to the 2026 rule, side by side
- Why it changed
- What to do and check on the job
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This section across NEC® editions
2020 NEC®No change
This section did not change from 2017 to 2020.
2023 NEC®No change
This section did not change from 2020 to 2023.
2026 NEC®NewYou're here
A surge protective device is now required when a new mobile or manufactured home replaces an old one on an existing service.
This is a plain-English summary, not the NEC®'s exact wording. Always check the full section in the NEC® edition your area has adopted, plus any local amendments.
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