Food and beverage manufacturing plants can be hostile spaces for electrical equipment. Electrical components are highly sensitive to contaminants, including essential industry ingredients like sugar, yeast, as well as cleaning agents.
There is also the threat posed by poor temperature management – particularly excess heat. All electrical equipment generate heat as a by-product of their operations, but if the temperature inside an electrical enclosure is not tightly regulated, it can wreak havoc with the output and lifespan with the componentry and mechanical drives within.
This essentially means that if the enclosure has to be sealed tightly enough to keep contaminants out, then some form of additional climate control must also be employed to remove this excess internal heat. Failing to do so could irrevocably damage the system.
In a nutshell, climate control is essentially a process of managing the internal temperature of an enclosure, inside which inverter drives, power supplies, contactors, PLCs, and other IT electrical and electronic components, are operating. By maintaining a stable temperature within an enclosure, operators can ensure that their electrical drives can work to their full potential, while avoiding the cost of repairing or replacing damaged components, as well as the loss of manufacturing time. Stopping one line for even the humblest of food products can cost a business tens of thousands of pounds per hour.
Normally, operators who are specifying climate control for enclosures have a large selection to choose from. But, as we’ve indicated, food and beverage manufacturing has its own set of challenges - and the primary consideration in this instance is which ‘Hygiene Zone’ will the equipment be placed in.
There are three different hygiene zones in food and beverage production plants, as defined by the BS EN 1672-2:2005 Standard.These zones determine an enclosure’s environment, cleaning regime, and potential exposure to contaminants.
Zone 1: Food Zone
Within this zone, surfaces can come into direct contact with foodstuffs which are returned to the product stream. These surfaces are therefore subjected to regular, if not continuous, cleaning regimes including spraying down with high-pressure cleaning fluid.
Only hygienic design (HD) enclosures and HD climate control equipment should be used in this area. They have no recesses or design features that could harbour germs and allow bacteria to build-up. They are also extremely robust and tightly sealed to ensure that they can withstand rigorous cleaning and high-pressure jets without allowing any water ingress to an ingress protection category of IP69 with the option to install additional cowls or covers as needed.
HD air-to-water heat exchange climate management systems can provide highly effective temperature management solutions for these enclosures while also meeting the requirements of the Zone 1 BS EN Standard. Air-to-water heat exchange systems transfer unwanted heat from within the enclosure to chilled water which is then transported away to a centralised cooling plant, possibly outdoors, where it can be dissipated. They don’t require a supply of ambient air so there is no need for louvres, and they only need simple housing which has no dirt traps and is therefore very easy to clean.
There is one other consideration, which is how to avoid condensation build-up. Any condensation within an enclosure can be a disaster for the equipment inside, posing a real safety risk with electrical devices and the potential for catastrophic failure if left unchecked. We recommend only using high quality industrial enclosures to prevent humid air from constantly entering the enclosure and combining this with a cooling unit featuring an integrated condensate evaporator. The cooling unit acts as a dehumidifier and removes excess condensate from the pocket of air within the sealed enclosure.
Zone 2: Splash Zone
This zone has surfaces that come into direct contact with foodstuffs which do not return to the product stream. However, these areas are still exposed to regular cleaning routines and its floors may be sprayed.
We strongly advise manufacturers to install stainless steel enclosures and climate control systems in this zone. Although there is no direct spraying of the enclosure or its associated climate control equipment, there may be some splashing, so a higher level of corrosion protection is advisable.
Rittal can supply its cooling unit range in stainless steel as an option.
Zone 3: Non-Food Zone
These are areas such as warehouses or logistical spaces where finished goods are transported either from or to the plant. There are no raw foodstuffs in this Zone.
It’s unlikely that there will be any rigorous cleaning regimes in these areas apart from the occasional sweeping of debris. It’s therefore acceptable (depending on your company’s specific guidelines) to either use mild steel or stainless-steel enclosures and climate control equipment, with the final choice determined by factors such as exposure to ambient temperature fluctuations – which can vary month on month.
In both Zones 2 and 3, there are a number of options for climate management systems, depending on the environment and ambient temperatures:
- In highly contaminated or dusty environments, systems that have sealed internal air-paths will ensure that contaminated air and particulate matter isn’t drawn into the enclosure.
- If the ambient temperature in a facility remains lower throughout the year than the desired temperature inside the enclosure, then either fan-and-filter units or air-to-air heat exchangers (both of which use the surrounding air to remove excess heat from the enclosure and dissipate it into the local environment) can be very effective.
- If the ambient temperatures rise above the required internal temperature, then units with active cooling circuits must be used. Examples of these include the aforementioned air-to-water heat exchange systems or wall/roof-mounted cooling units which use a refrigerant as an intermediate medium to remove the excess heat from enclosures before transferring this to the surrounding ambient air.
Closing Thoughts
The best course of action is to have your existing cooling equipment surveyed by a specialist. Rittal are happy to offer you a free RiAssure Cooling Inspection with one of our trained representatives. You will get honest, clear advice on your existing equipment and its suitability within the chosen environment/process and a short report which includes the next best steps for your installation.
These next steps could range from how to maintain the life of your existing equipment or the replacement of units that are either undersized or inefficient to help improve performance and increase the efficiency of your site.
