Flexible cords and cables used to connect the moving parts of turbines shall be.

• A. Suitable for extra-hard usage
• B. Identified as hard service cord
• C. Listed as for outdoor use
• D. All of these

Answer: (D)

Flexible cords used with moving turbine parts face constant bending, vibration, heat, oil, and weather. To hold up in that demanding environment, the cord needs several protections: extra-hard usage indicates it can handle severe flexing and harsh conditions; identified as hard service cord shows it’s approved for rough service environments; and listed for outdoor use confirms it’s rated for weather exposure. Each of these attributes targets a different aspect of the harsh operating conditions, so a cord that meets all of them is required. That’s why selecting a cord that is suitable for extra-hard usage, identified as hard service cord, and listed for outdoor use is the correct approach.