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Notice:
NEC is a registered trademark of the National Fire Protection
Association, Inc. All NEC references by Electrical Helper are
interpretations of the NEC by the Electrical Helper staff and are not
NEC statements. The official position of the NEC requires that the NEC
be referred to in its entirety. |
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Article 430.72(B) |
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1) |
Separate Overcurrent Protection. Where the motor
branch-circuit short-circuit and ground-fault protective device
does not provide protection in accordance with 430.72(B)(2),
separate overcurrent protection shall be provided. The
over-current protection shall not exceed the values specified in
Column A of Table 430.72(B).
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2) |
Branch-Circuit Overcurrent Protective Device. Conductors shall
be permitted to be protected by the motor branch-circuit
short-circuit and ground-fault protective de-vice and shall
require only short-circuit and ground-fault protection. Where the
conductors do not extend beyond the motor control equipment
enclosure, the rating of the protective device(s) shall not exceed
the value specified in Column B of Table 430.72(B). Where the
conductors ex-tend beyond the motor control equipment enclosure,
the rating of the protective device(s) shall not exceed the value
specified in Column C of Table 430.72(B). |
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Table 430.72(B) Maximum Rating of Overcurrent Protective Device in
Amperes |
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Protection Provided by Motor Branch-Circuit Protective Device(s) |
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Column A |
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Column B |
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Column C |
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Separate Protection |
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Conductors Within |
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Conductors Extend Beyond |
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Provided |
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Enclosure |
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Enclosure |
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Control |
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Circuit |
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Aluminum or |
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Aluminum or |
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Aluminum or |
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Conductor |
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Copper-Clad |
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Copper-Clad |
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Copper-Clad |
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Size (AWG) |
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Copper |
Aluminum |
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Copper |
Aluminum |
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Copper |
Aluminum |
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18 |
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7 |
- |
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25 |
- |
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7 |
- |
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16 |
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10 |
- |
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40 |
- |
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10 |
- |
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14 |
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(Note 1) |
- |
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100 |
- |
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45 |
- |
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12 |
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(Note 1) |
(Note 1) |
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120 |
100 |
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60 |
45 |
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10 |
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(Note 1) |
(Note 1) |
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160 |
140 |
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90 |
75 |
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Larger than 10 |
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(Note 1) |
(Note 1) |
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(Note 2) |
(Note 2) |
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(Note 3) |
(Note 3) |
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Notes: |
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1. Value specified in 310.15 as applicable. |
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2. 400 percent of value specified in Table 310.17 for 60°C conductors. |
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3. 300 percent of value specified in Table 310.16 for 60°C conductors. |
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