Other Concerns

DOE-HDBK-1092-2004

contacting noncurrent-carrying metal parts. This may be accomplished by use of pressure

terminal connectors, soldering lugs, crimped eyelets, or soldering all strands of the wire

together.

9.4.2.4 OTHER CONCERNS

Conductors shall not be bundled together in such a way that the temperature rating of the

conductors is exceeded. Bundled conductors may require derating of their ampacities. For

example, see NEC 310.15(B)(2) and Table 310.15(B)(2)(a)

Flexible cord should be listed or labeled and used only in continuous lengths without splice or

tap when initially installed.

Repairs are permitted if the completed splice retains the insulation, outer sheath properties, and

usage characteristics of the cord being spliced. In most instances, the entire length of flexible

cord should be replaced, in order to assure integrity of the insulation and usage characteristics.

9.4.3

POWER SWITCHES AND INTERLOCK DEVICES SPECIFIC

REQUIREMENTS

For all electrical/electronic enclosures utilizing power switches or interlocks, the following should

apply:

1. Interlocks should be utilized where exposed voltages (50 volts or greater) are present in

equipment and access to the exposed live parts is not controlled (See Section 9.6.4).

2. Ensure all line-side unprotected contacts are guarded on interlocking contactors or other

switching equipment.

3. Be suitable for the conditions, use, and location.

4. Circuit breakers used for the equipment power switch will be rated for switching under load.

5. Provide provisions for lockout/tagout requirements.

9.5

CHASSIS POWER DISTRIBUTION

Manufacturers are responsible for determining the safety of such chassis and/or enclosures and

for providing documentation showing how that determination was made. Listed equipment

should be selected by design when available. Unlisted commercial equipment and in-house

fabricated equipment shall be approved by the local AHJ.

9.5.1

AC POWER DISTRIBUTION

9.5.1.1 CHASSIS BONDING AND GROUNDING

Metal chassis shall be effectively bonded to a main grounding point in the rack cabinet where

necessary to assure electrical continuity and shall have the capacity to conduct safely any fault

current likely to be imposed on it. (NEC 250.96)

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