The missing knockout on the bottom right hand side of this metal electric meter socket enclosure was the reason why this inquisitive young squirrel was electrocuted. The meter reader discovered the squirrel when he removed the electric meter so it could be replaced with a new one. Section 373-4 requires unused openings in enclosures of this type to be effectively closed to afford protection substantially equivalent to that of the enclosure. It reminds me of the story that we included in the January 2000 column showing the snake and mouse who were also electrocuted when they found their way into energized electrical equipment through an unsealed raceway. See Section 230-8.
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