According to NEC Article 300.45, what criteria pertain to motor conductors?

The criteria outlined in NEC Article 300.45 that pertain to motor conductors emphasize sizing and installation methods. Proper sizing is crucial to ensure that conductors can handle the current required by the motor without overheating, which could lead to insulation failure and potentially cause fires. Additionally, the installation methods are important because they dictate how safely and effectively the conductors are run, particularly in relation to protection from physical damage, appropriate bending radius, and securing in place.

Sizing ensures that the conductor has adequate ampacity for the motor's load, while installation methods align with safety rules regarding proper routing, separation from other systems, and adherence to environmental conditions. Both aspects work together to ensure reliability and safety of the motor's electrical supply.

Considering the other options: durability and flexibility, voltage ratings, and grounding techniques, while important in their own contexts, do not specifically address the comprehensive aspect of sizing and installation methods for motor conductors as specified in the NEC Article. These criteria are inherently linked to the performance and safety of motor installations, which is why they are emphasized in this code section.