What is a cable cleat

The international standard governing Cable Cleats used in electrical installations is IEC 61914:2015. In this standard Cable Cleats are defined as “devices designed to provide securing of cables when installed at intervals along the length of the cables”. Simply put, cable cleats are used to secure, fix and route electrical cables in the positions required in an electrical installation. They can consist of single or multiple parts, plastic or metal material and include some sort of provision for securing to a surface or structure. Mounting surfaces that may be specified include; ladder, tray, strut, rail, and beam.

Cable cleats are designed to ensure that cables are fixed, supported and routed in a manner that provides safe operation and reduces the risk of damage or injury in the event of a short circuit fault, emergency or accident. Improper clamping of cables can result in loss through unnecessary downtime or even injury and death. Cable cleats should at a minimum:

• Be rated for the specified cable OD.
• Provide a means of securely fixing the cable.
• Have adequate strength to secure the cable.
• Prevent excessive cable movement and damage.
• Avoid chafing and undue stress in the cable.

Cleat Selection and How to Specify Cable Cleats

Cable Arrangement – The cable arrangement/configuration will primarily dictate the type of cleat required. Cable arrangements for 3 phase installations utilising single conductor cables are typically flat spaced, flat touching or trefoil. A parallel or flat arrangement of single core cables can be completed with a range of single or two-part cleats. Whereas a trefoil would require a trefoil type cleat.

Cable Type – The type of cable being used, Single or Multi-core, as well as its Voltage Levels and Construction Low Voltage (LV), Medium Voltage (MV) or High Voltage (HV) should be considered.

Cable Diameter – Knowing the overall diameter of the cable (measurement across the entire cross-section) is essential in ensuring the correct size of cleat is selected. It is also required to calculate the short circuit forces that the cleat may be subjected to; this can be used to determine correct cleat spacing.

Performance

A range of factors will dictate the level of performance your installation will require. The size, weight and length of run of the cable and spacing will usually influence whether you require a polymer or metallic cleat. Things such as the support structure material and environmental conditions (corrosion) can also affect your decision of cleat material. Other factors such as project specification may require special provision for performance in the event of a fire such as Low Smoke or Zero Halogen.

In summary, to correctly select the type of cleat you require you should be looking to obtain the following information;

1. Calculate the system peak fault current.
2. Confirm cable type and arrangement, including the overall diameter and manufacturing tolerance.
3. Confirm the support structure type and material
4. Consider any other environmental conditions and project specification requirements.

CCG’s range of stainless-steel single and trefoil cleats.

Designed to restrain single or trefoil cables onto ladder tray or strut systems and are manufactured from corrosion resistant, magnetic free, 316 stainless steel with LSOH and UV protected polymeric linings for cable protection. CCG’s cleats are designed to withstand mechanical forces caused by fault currents of up to 180kA.

CCG’s range of cleats have an open hinge single bolt fastening system allowing ease of installation for a wide range of cables from 13mm to 128mm.