Requirements on sensors in the F&B Industry
The requirements on sensors from the view of the F&B Industry correspond to expectations at the glance. However, for the second view a set of differentiations shows up.
The emphases of the requirements
June 20th, 2010 - The product criteria regarding sensors are naturally determined by the high hygiene requirements in the F&B Industry.
With 65% two thirds of all denominations highlight the high type of protection of the sensors.
High-grade steel versions with sensor case or wirings as well as the requirement that the sensors at the machine must have to be cleaned „well“ account for 27% of the denominations.
Special cable jacket and explosion-proof version add to 8% of the denominations.
High type of protection is differentiating
First the differentiation is related to different high type of protection.
- „Minimum requirement for components in the field is IP 54 or IP55. In particular IP 65/IP 67 are used for sensors everywhere where moisture is and where gases can result i.e. also in the fermentation and maturing. This concerns the filling as well.“ (Beverage industry)
- „Although IP 65 is already a very high type of protection some manufacturers already offer IP 66, which is favourable for the continuous operation. One has many problems with the condensation and hot/cold temperature changes. So in particular one uses light barrier/push-buttons with integrated heaters.“ (Meat and fish industry)
- „Beside certain hygiene-technical specifications that have to be fulfilled, above all a very high protection against moisture must be ensured. Type of protection IP 68 or 69 would not be bad at all,however, the minimum is IP 65.“ (Meat and fish industry)
Different type of protection show up for the wet and drying sector.
- „One distinguishes between the wet and the drying sector, both have different requirements. In the wet sector with the filling the polyester filler is made clean and alkaline skillfully carried out with pressure water and much chemistry. Therefore one demands IP69 k or IP 67. Though IP 65 e.g. with light barriers works but one has discovered that the light barriers with higher type of protection are more expensive but longer in operation. Therefore one persists that this type of protection is actually installed. On the other hand the components in the drying sector are subject rather to large mechanical exposure because pallets fall sometimes on the sensors.“ (Beverage industry)
- „Corrosive cleaning agents play a role in the wet sector, so the components should be water-protected. If necessary, one demands type of protection to IP 67.“ (Meat, fish industry)
High-grade steel version for special use
Sporadically the request occurs to have „everything in high-grade steel“.
- „One would prefer to have everything in high-grade steel“. (Fish industry)
However, high-grade steel versions are mainly reserved for special applications according to the decision-makers.
- „Partial V4-boxes for sensors at the polyester filler are important.“ (Beverage industry)
- „Also with sensors, which have contact with the product, high-grade steel VA is prescribed. This concerns in particular the sector, where the chips come into the roasting machine. Here there are many feeding equipments, conveyor belts and vibration rollers. However, with the packing machines the high-grade steel version is no longer in demand. Altogether about half of the machines are affected by the requirements to high-grade steel version“. (Baking industry)
To clean well
In the general HACCP hygiene specifications the cleaning is contained:
- „Product criteria are aligned 1. to water protection, 2. to hygiene design i.e. whether one can clean the things well. Only those converters are excluded from these criteria that are installed in the control cabinet but all converters near the motors and the sensors must fulfill these criteria.“ (Meat, fish industry)
- „Here I could call at least 20 different things depending on component and field of application. The aspects of hygiene are in particular important for the filling. Here no “dirty corners” may occur. So for example with the last project the requirements regarding the output modules were at IP 68 because of the sensitivity to splash-water in the brewing house.“ (Beverage industry)
Special cable jacket
A special cable jacket is to prevent that the cable of the sensor becomes brittle after some time.
- „There are in particular cable problems. Usually the cables become inflexibly after 1-2 years. If new cables are reinstalled, the insulations of the sensor cable usually break up.“ (Baking industry)
A further aspect stresses the experience that connectors directly at the sensor do not maintain high pressure cleaning for a long time.
- „Further no water may penetrate the cable entry. At present the market offers only 2 sensor versions; one with one cable entry and 4 m cables and the other version with a connector directly at the sensor; an intermediate thing would be beautiful here because if the connector is close to the sensor it does not maintain for a long time in the high cleaning sector. On the other hand one would avoid to renew the total cable length.“ (Meat, fish industry)
These results are based on interviews with 120 of the 415 large enterprises (=29%) in the six turnover-strongest sectors of the German F&B Industry.