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Article 240 Low Res - Modem [1695Kb] Hi Res - Cable/DSL [5622Kb]        Page 7 of 8
Overcurrent Protection

240.85 Applications

The second paragraph was revised and an FPN was added to read:

A circuit breaker with a straight voltage rating (240V or 480V) can be used on a circuit where the nominal voltage between any two conductors does not exceed the circuit breaker’s voltage rating. A 2-pole circuit breaker cannot be used for protecting a 3-phase, corner-grounded delta circuit unless the circuit breaker is marked 1 or 3-phase to indicate such suitability. Figure 240-5

A circuit breaker with a slash rating such as 120/240V or 480Y/277V can be used on a solidly-grounded circuit where the nominal voltage of any one conductor to ground does not exceed the lower of the two values and the nominal voltage between any two conductors does not exceed the higher value.


Figure 240-5
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