Intermediate Restraints are cable restraining devices designed to be used with cable cleats, without being attached to the mounting surface, to hold the cables together in order to provide resistance to electromechanical forces.
All CMP’s Intermediate Restraints have been designed, constructed, and third party tested and certified in accordance with the International Standard ‘cable cleats for electrical installations’ IEC 61914.
CMP offers two types of Intermediate Restraint, the SDSSIR range and the STR range. The SDSSIR range is designed and tested for use with the Patriot (SDSS), Huron (LDAL) and Reliance (SDAL) cable cleat, whilst the STR type is available in standard duty and heavy duty for use with all other cable cleats. All types are manufactured in 316L stainless steel, providing excellent corrosion resistance, and have Low Smoke and Fume (LSF) liners as standard.
All types of Intermediate Restraint are designed to be installed at mid-point between cable cleats.
The use of Intermediate Restraints as part of the cable management system can be a safe cost-effective method when compared to a cable cleat only installation, reducing the number of cable cleats by 50% in most systems. In addition to this cost reduction, installation time is also reduced by employing a cable cleat and intermediate restraint solution when compared to cable cleat only installations, as the intermediate restraint is not secured to the mounting surface.
The above table should be used as a guide for the selection of the correct intermediate restraints to be installed with the desired cable cleat, this will be dependent on the installation parameters such as the short circuit fault conditions and centre-to-centre conductor distances. Even when relatively low short circuits are anticipated which produce relatively low electromechanical forces, CMP advises the use of intermediate restraints for installations where cable cleats are spaced 1200mm or greater. These intermediate restraints should be installed at mid-point between cable cleats to prevent unnecessary ‘bird caging’ effects, which can cause damage to the cables and to other surrounding equipment, as well as potentially personnel whom may be in the vicinity during such a short circuit fault.
Without Intermediate Restraints
With Intermediate Restraints