Strain Relief

DOE-HDBK-1092-98

4. Where the fastening means and mechanical connections are specifically designed to permit ready

removal for maintenance and repair.

5. For data processing cables approved as part of the data processing system.

6. For temporary wiring.

Where breaking or loosening of a circuit connection would render an electric shock or could result

in a fire, such connection shall be made mechanically secure. Mechanical security of connections

may be provided by crimped, closed ring or flanged lug, or a wrapping that forms at least an open

U or by cable clamps, or by cable lacing, insulating tubing, or similar means.

9.4.2.2 STRAIN RELIEF

Wiring, cords, or cables shall be provided with strain relief as required to prevent damage.

Additional insulation may be required when the construction of the strain relief may damage the

insulation. The use of type NM (Romex) cable clamps on flexible cords and cables is not permitted.

Use listed or labeled clamps. The use of any metal clamp or other means that may cause undue stress

on the cables within or external to instrument racks is not allowed. Cord and cable support for AC

power cable or other heavy duty or large diameter cables must distribute the load over a large area

of the outer covering of the cable.

9.4.2.3 SEPARATION OF VOLTAGES

Insulated conductors of different circuits shall be separated or segregated from uninsulated live parts

connected to different circuits unless provided with insulation suitable for the highest voltage

involved.

Segregation of insulated conductors may be accomplished by clamping, routing, or equivalent means

that provide permanent separation from insulated or uninsulated live parts of a different circuit.

Loose strands of stranded internal wiring, connected to a wire-binding screw, shall be prevented from

contacting other uninsulated live parts not always of the same potential and from 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.

Flexible cord should be 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.

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