Uptime and efficiency with retrofit cable protection
Any loss of power or data can be catastrophic for a busy production site, affecting both operational efficiency and safety. It is therefore critical to specify cable protection correctly to ensure uninterrupted performance and to avoid the high cost of lost production.
However, what is the best route to take when vital electrical cabling needs protecting, after it has been installed?
While cable protection is always easier to carry out during electrical installation, there are many scenarios where vital electrical cables need to be protected after they have been installed. This may be because the requirement is identified at a later stage, or where existing cable protection is worn, or damaged and new options need to be retrofitted.
Alex Smith, Technical Director at flexible conduit manufacturer, Flexicon, identifies some of the areas to consider when specifying retrofit cable protection systems. He will explain how selecting the right system can help reduce installation time while protecting vulnerable or existing cabling that may be susceptible to damage from a wide range of external factors.
He will then detail some of the other considerations for specifiers when considering cable protection, such as the choice of material, or even whether to opt for bespoke-designed cable protection.
Retrofitting cable protection has traditionally been a complex and lengthy task, with the installer required to pull existing cabling through the open end of a conduit system.
Conduit system manufacturers have been offering slit conduit options for some time, enabling installers to wrap insert the existing cabling to avoid disruption. However, it is important to ensure that the choice of flexible conduit system continues to offer the appropriate levels of protection for the environment and does not leave any areas of cabling or the installation exposed.
Divisible conduits, such as the new Flexicon FPADS range, allow existing cabling to be inserted laterally via a slit opening. This product consists of two open conduit profiles, which then interlock to form a protected IP40 system around the cables.
It is also important to consider the cable routing. Traditional split conduit options can potentially expose cabling when bent or routed around corners, whereas the newer, divisible conduit options will maintain more mechanical strength and continuous protection of the cabling irrespective of orientation or routing due to their interlocking design.
Termination and fittings
All cable protection should be specified as a complete end-to-end system, taking into account not only the flexible conduit used, but the range of termination and fittings used too.
This has traditionally been a complex area for installers, as there has been less focus on design innovations for fittings and accessories. This can make it a cumbersome task to terminate cabling in a retrofit application, however, manufacturers are now offering an improved range of options to make this easier.
Flexicon’s FPADS range for example. includes a hinged fitting and locknut, compatible with the 21 mm size divisible conduit, to provide an easy and secure termination option.
Protecting new cabling
As well as considering retrofit options, specifiers may also be tasked with installing new electrical cabling at the same time.
In this scenario, there is a broader range of options available and specification should take into account the range of external hazards that the cabling may be exposed to; whether that is to meet a certain IP rating, enhanced fire performance properties, resistance to chemicals or UV exposure to name a few.
The performance of cable protection solutions available on the market can vary greatly so customers should always check suitability and compatibility for their application.
Nylon, metal or composite?
Where fatigue life or impact resistance is important, installers should consider nylon polyamide (PA) corrugated flexible conduits, which can offer high impact strength and recovery if crushed combined with excellent temperature performance.
Polypropylene and PVC conduit systems are available; however, both of these systems are inferior to nylon polyamide (PA) when it comes to fire performance, resistance to solvents and their abrasion resistance properties.
With no exposed metallic content, non-metallic conduits do not rust or corrode thus maintaining performance and appearance over time. In addition, it is worth considering labour and installation time. Non-metallic systems are often quicker to install than metallic options as they are easier and faster to cut. Non-metallic fittings will typically be one piece and simply push on and twist to secure.
For installations subject to increased UV exposure, it is important when specifying non-metallic and polymer-coated metal conduit to consider that ultraviolet (UV) radiation will naturally degrade any plastic materials. Failure could result in materials cracking, an increase in brittleness, reduced flexibility and lower impact strength.
Metallic flexible conduit typically has a higher level of crush resistance, high mechanical strength and can provide excellent EMC screening properties. Metallic systems in particular are ideal for applications that require a very high compression or pull-off strength, or where there is the need to protect cables from exposure in hazardous environments.
Composite products, such as plastic sheathing on metal conduits, metal over-braiding or metal threads on plastic fittings can also offer the ideal combination of light weight and high strength.
For more complex application requirements, customers should speak to their supplier to discuss bespoke options.
These could include conduit supplied in non-standard or pre-cut lengths, in larger or smaller diameters or with different thread termination or fitting options. Additionally, more complex requirements, such as altering performance characteristics to meet a certain temperature requirement, compression strength or abrasion resistance or to achieve a greater fatigue life may also be considered.
Flexicon offers a design prototype service which allows customers to see new cable protection concepts, before investing in a full system solution. The service also includes bespoke testing and the preparation of customer samples for field trial and analysis.
Flexicon products are designed, tested and manufactured in the UK and its team of engineers are working continuously on tomorrow’s cable protection solutions. Its research and development team works with customers and has the facility to create 3D printed solutions to prove customer concepts.
For further information about selecting the appropriate flexible conduit system for your installation, please visit www.flexicon.uk.com or contact firstname.lastname@example.org