04. Why are cable cleats required?

Unrestrained vs. Restrained Cables

The left photo depicts unsupported cables resulting from cable tie failures.  On the right the cables are properly restrained by Talon® cable cleats.

Cable cleats are required for the securing and retention of cables.  This protection is especially important when cables are exposed to axial, lateral or torsional forces, such as those caused by the weight of cables in vertical runs or short circuit fault currents.  From a regulatory compliance perspective, proper cable retention facilitates conformance to electrical installation standards.  For example, NFPA-70-2017, The (US) National Electrical Code, NEC Article 392.20 (C) requires single conductors to be “securely bound in circuit groups to prevent excessive movement due to fault-current magnetic forces.”  In that same Code, Article 110.36 requires insulators used as supports for single conductor cables to be “capable of safely withstanding the maximum magnetic forces that would prevail if two or more conductors of a circuit were subjected to short circuit current.”  Other national wiring standards contain similar provisions for cable retention and protection from electromechanical forces.

Some installers mistakenly place cables in clamps that are designed for pipe or conduit, or they improperly apply cable ties or banding and damage the cable sheath or compress the insulation.  Electrical inspectors should be vigilant about correcting such misapplications to ensure cables are restrained by products that are tested and suitable for the application and provide long-term cable protection.