240.67 Arc energy reduction (fuses)
What changed in 240.67
Another way to reduce arc energy was added, documentation rules grew, and the system must be tested when installed.
Point by point
- Still applies where fuses of 1,200 A or larger are installed, and the January 1, 2020 effective date carried over.
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- 4 more points on exactly what changed
- The 2017 rule next to the 2020 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®RevisedYou're here
Another way to reduce arc energy was added, documentation rules grew, and the system must be tested when installed.
2023 NEC®No change
This section did not change from 2020 to 2023.
2026 NEC®No change
This section did not change from 2023 to 2026.
More 2020 changes in Article 240
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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