wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
Change:
240.4(G) Overcurrent Protection for Specific Conductor Applications.
Overcurrent protection for specific conductors shall be permitted to be provided as referenced in Table 240.4(G).
[Add table entry: "Service Conductors - 230.90"]
Substantiation:
230.90(A) Exception 3 permits service conductors supplying two to six service OCPDs to have an ampacity of less than the sum of the ratings of those OCPD, as long as the ampacity is no less than the calculated load. When using this exception, the resulting conductor size does not comply with 240.4; the conductors are not "protected against overcurrent in accordance with their ampacity." Therefore this application requires an entry in Table 240.4(G), to allow following the rules in 230.90 rather than the base rule of 240.4.
Note that this is analogous to the allowance found in 240.21(D) on the location of overcurrent devices. Service conductors require special treatment for both 240.4 and 240.21.
240.4(G) Overcurrent Protection for Specific Conductor Applications.
Overcurrent protection for specific conductors shall be permitted to be provided as referenced in Table 240.4(G).
[Add table entry: "Service Conductors - 230.90"]
Substantiation:
230.90(A) Exception 3 permits service conductors supplying two to six service OCPDs to have an ampacity of less than the sum of the ratings of those OCPD, as long as the ampacity is no less than the calculated load. When using this exception, the resulting conductor size does not comply with 240.4; the conductors are not "protected against overcurrent in accordance with their ampacity." Therefore this application requires an entry in Table 240.4(G), to allow following the rules in 230.90 rather than the base rule of 240.4.
Note that this is analogous to the allowance found in 240.21(D) on the location of overcurrent devices. Service conductors require special treatment for both 240.4 and 240.21.