Figure 2-4. Minimum clearances in front of electrical equipment (over 600 V)

DOE-HDBK-1092-2004

2.9.2

ELECTRICAL EQUIPMENT RATED OVER 600 VOLTS

NEC 110.34 lists minimum clearances required for working spaces in front of high-voltage

electrical equipment such as switchboards, control panels, switches, circuit breakers,

switchgear, and motor controllers.

There are three conditions to apply:

1. Where there are exposed live components on one side of a space and no live or

ungrounded parts on the other side.

2. Where there are exposed live components on one side and grounded parts on the other

such as concrete, brick, and tile walls that are considered to be grounded parts.

3. Where there are exposed live components on both sides.

See Figure 2-4 for the clearance requirements in front of electrical equipment rated at over 600

V. See NEC for clearance requirements in the rear of electrical equipment.

NEC Table 110.34(A)

Figure 2-4. Minimum clearances in front of electrical equipment (over 600 V).

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