Electrical and data cables keep modern food processing plants operational and efficient, yet they are subject to one of the harshest environments possible and could be a source of contamination; getting cable protection right is vital states Tim Creedon, Sales and Marketing Director at Flexicon Ltd.
As food and drink processing plants become increasingly automated, equipment becomes ever more reliant on electrical systems, controls and automation. In this drive to further improve efficiency any unplanned downtime can result in significant lost revenue through lost production.
This makes reliance on power and data cabling vital, so it is not surprising that many engineers decide to over specify cable protection in a better safe than sorry approach.
It is not always the optimum solution, however, particularly in a cost competitive industry where there is already significant pressure on margins. Striking the balance between complete cable protection and the most cost effective solution requires a clear understanding of the hazards faced by equipment in the industry. Added to this is the insurance that any system does not in itself create a food safety hazard by eliminating any possible food or bacteria traps.
Perhaps it is out of fear, but too many outdated rules of thumb exist in the industry – such as an over reliance on specifying metallic flexible conduit systems.
Metallic conduit typically has an inherent toughness and a high level of crush resistance, but the technology of non-metallic conduits has advanced dramatically meaning that they can often offer a tough enough solution, at a fraction of the price.
Our metallic systems range for instance offers compression strengths starting at 45kg/100mm going up to 570kg/100mm, whereas our non-metallic food grade PVC conduits offer compression strength of 120Kg/100mm.
At face value some may opt for the metallic option, but take a look at the installation. Even where compression strength and crush resistance might be an issue, in all but the most extreme cases 120kg/100mm is more than adequate.
Specifying your cable protection based on one property alone is likely to be a mistake. The first step is to analyse what you are protecting the cabling from and then choose the most appropriate system.
Highly Hygienic
One obvious hazard is resistance to water ingress, with equipment regularly washed down using high-pressure steam jets to ensure hygiene. Selecting the correct conduit system, including the fitting, specifiers should be providing protection to an IP rating of up to IP69.
Equally as important in the food industry is the design of equipment to avoid food traps where debris, bacterial or fungal growth could occur. Food grade, flexible conduit systems are designed using the same fundamentals, with the conduit having smooth wipe clean surfaces and fittings that are designed using the principles given in EN 1672-2:Food Processing Machinery – Hygienic requirements and EN ISO 14159.
Particular care must be taken with fittings because the interface between the equipment and power and data could trap microscopic material.
Flexicon’s food grade stainless steel fitting for instance is as round as possible with a minimum area of flats for tightening. It also includes a number of blue coloured compression seals to prevent any ingress of material or bacteria developing between the fitting, equipment and conduit.
It can be used with both LTP metallic conduit and LPC non-metallic conduits to form a complete liquid tight hygienic system.
Hazard identification
Other hazards that cabling may face include both high and low temperatures, chemicals such as cleaning materials or from acidic food products, tensile or pull off strength, abrasion, vibration and EMC screening.
On top of this there can also be some applications in the food industry that fall under ATEX requirements, for example in a flour mill where dust in the air may form a potentially explosive environment. Electrical equipment and cabling in such areas is a potential source of ignition so, depending on the exact nature of the explosive atmosphere, either Ex d flameproof barrier glands or Ex e increased safety and dust ignition proof fittings can be needed as part of a liquid tight conduit system.
However long the list of hazards, it is unlikely to be exhaustive and not all of the factors will be relevant to all applications.
What is certain however is that a modern food or drink processing plant relies more than ever on data and power and there is increasing pressure on it to remain fully operational. Getting the cable protection right is therefore critical and must not be an afterthought.
The best approach is to conduct a thorough and exhaustive risk analysis to identify all of the hazards faced by cabling, which could vary from area to area, and then make the most appropriate specification. Reputable UK based manufacturers should be able to provide you with the correct advice and technical help either over the phone or via a site visit.
Contact Details:
Flexicon Ltd
Roman Way
Coleshill
Birmingham
B46 1HG
Tel: +44 (0)1675 466900
Email: sales@flexicon.uk.com
Web: www.flexicon.uk.com
