Regarding the selection of industrial cables, consider the following:1.XLPE insulated cables have a higher continuous operating temperature than PVC cables.2.The short-circuit rating of a cable is independent of the insulation material.3.Voltage drop calculation is mandatory for selecting long cable runs.Which of the statements given above is/are correct?

Correct Answer: C - 1 and 3 only

Quick Concept Explanation

Industrial cable selection must satisfy current-carrying capacity, voltage drop, installation conditions and short-circuit withstand. XLPE insulation generally permits a higher continuous conductor temperature than PVC. Key relation: Voltage drop≈I(R cosφ+X sinφ)L; adiabatic short-circuit relation I²t≈k²S².

Exam focus: Check ampacity, voltage drop and short-circuit withstand together. Common trap: Cable short-circuit rating is not independent of insulation temperature limits.

Statement-wise Verification

• Statement 1 - Correct.
  XLPE insulated cables have a higher continuous operating temperature than PVC cables.
  XLPE insulation generally permits a higher continuous conductor temperature than PVC.
• Statement 2 - Incorrect.
  The short-circuit rating of a cable is independent of the insulation material.
  Permissible conductor temperature during a short circuit depends on insulation and cable construction, affecting short-circuit rating
• Statement 3 - Correct.
  Voltage drop calculation is mandatory for selecting long cable runs.
  Industrial cable selection must satisfy current-carrying capacity, voltage drop, installation conditions and short-circuit withstand.

Core Concept

Industrial cable selection must satisfy current-carrying capacity, voltage drop, installation conditions and short-circuit withstand. XLPE insulation generally permits a higher continuous conductor temperature than PVC. Short-circuit thermal capability depends on conductor material, cross-section and allowable initial/final temperatures, which are linked to insulation construction.

Formula / Key Relationship

Voltage drop≈I(R cosφ+X sinφ)L; adiabatic short-circuit relation I²t≈k²S².

Why the Other Options Are Wrong

Option A is incorrect because it includes incorrect statement(s) 2 and omits correct statement(s) 3. Option B is incorrect because it includes incorrect statement(s) 2 and omits correct statement(s) 1. Option D is incorrect because it includes incorrect statement(s) 2.

Exam Shortcut / Approach

Check ampacity, voltage drop and short-circuit withstand together.

Common Mistake

Cable short-circuit rating is not independent of insulation temperature limits.

Quick Revision

XLPE Temperature Short-Circuit and Voltage Drop is linked with Cable Selection, Cables and Industrial Electrical Systems. Check ampacity, voltage drop and short-circuit withstand together.