590.8 Temporary overcurrent devices
What changed in 590.8
For temporary services, current-limiting overcurrent devices are now only required on certain 3-phase wye systems when the available fault current is over 10,000 amps.
Point by point
- Applies to solidly grounded, 3-phase, wye-connected temporary services over 150 volts to ground and up to 1,000 volts line to line.
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- 2 more points on exactly what changed
- The 2020 rule next to the 2023 rule, side by side
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This section across NEC® editions
2020 NEC®Revised
Reused overcurrent devices must be examined before going into temporary wiring, and temporary services over 150 volts to ground on grounded wye systems need current-limiting devices.
Open the 2020 page →2023 NEC®RevisedYou're here
For temporary services, current-limiting overcurrent devices are now only required on certain 3-phase wye systems when the available fault current is over 10,000 amps.
2026 NEC®No change
This section did not change from 2023 to 2026.
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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