Table 130.4(E)(b) in the NFPA 70E provides shock protection approach boundaries to exposed energized electrical conductors or circuit parts for direct-current systems.
On the left side of the table is the nominal potential difference for the equipment being worked on. On the right side of the table is the restricted approach boundary. In the middle of the table is the limited approach boundary based on one of the two conditions:
Example: A 500-volt DC circuit would have a nominal potential difference of 500 volts DC when measured positive to negative. This results in using the 301 V–1 kV row in the table.
In the example, the limited approach boundary for an exposed fixed circuit part is 3 foot, 6 inches. The restricted approach boundary is 1 foot.
Refer to the image of Table130.4(E)(b) to answer the question below.
Refer to the image of Table130.4(E)(b) to answer the question below.
What is the limited approach boundary for an exposed fixed circuit part operating at 70kV?
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