Once the correct cable has been determined, it can be described in a cable specification. Cable specifications generally start with the conductor and progress radially through the insulation and coverings.

The following is a check list that can be used in preparing a cable specification:

a) Number of conductors in cable, and phase identification required

b) Conductor size (AWG, kcmil) and materialPublish Post

c) Insulation (rubber, polyvinyl chloride, XLPE, EPR, etc.)

d) Voltage rating, and whether system requires 100%, 133%, or 173% insulation level

e) Shielding system, required on cable systems rated 8 kV and above and may be required on systems rated 2001-8000 V

f) Outer finishes

g) Installation approvals required (for use in cable tray, direct burial, messenger supported, wet location, exposure to sunlight or oil, etc.)

h) Applicable UL listing

i) Test voltage and partial-discharge voltage

j) Ground-fault-current value and time duration

k) Cable accessories, if any, to be supplied by cable manufacturer

An alternate method of specifying cable is to furnish the ampacity of the circuit (amperes), the voltage (phase-to-phase, phase-to-ground, grounded, or ungrounded), and the frequency, along with any other pertinent system data.

Also required is the installation method and the installation conditions (ambient temperature, load factor, etc.). For either method, the total number of linear feet of conductors required, the quantity desired shipped in one length, any requirement for pulling eyes, and whether.

This guide is recommended under IEEE Std 141-1993

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