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Terms


Flush mountable sensors
are particularly suitable for detecting solid objects without direct contact and for level sensing when mounted flush in a container or hopper through non-metals partitions.

The non-flush mountable sensors
are designed for applications, in which the medium to be monitored comes in direct contact with the sensor. In such level monitoring systems, the sensor head is completely immersed in the powder, granulate or liquid. Alternatively detection through a glass or plastic wall.

ATEX certified products
include capacitive and inductive proximity sensors in various size. NAMUR sensors and proximity sensors with NPN or PNP transistor output. With the Ex-protected barriers and amplifiers the product range is complete. The ATEX-certified units are available for areas with danger of gas explosion (Zone 0,1 and 2) and for areas with danger of dust explosion (Zone 20, 21 and 22). Being an A T E X certified firm, RECHNER can also offer sensors with a manufacturers declaration for both of these explosion danger areas.

High Performance sensors
are capacitive sensors of the new generation. High Performance, just two words that accurately describe the new generation of standard sensors: Capacitive sensors with 3 times higher sensing distance than the norm, high temperature stability up to 100°C and excellent EMC-characteristics. The sensing distance is medium optimised, so that with just one adjustment it is possible to detect a variety of products. The series comprise capacitive sensors in cylindrical size from M 8 x 1 mm to 64 mm in diameter, with both flush and non-flush mountable models. Also ranging among the standard are chemical resistant and food-grade sensors in PTFE or PTFE/stainless steel housings, brass, PTFE, PEEK, PPO, PA ,PVDF and others.

Capacitive sensors - NormLine
Capacitive sensors, just like inductive and optical sensors are subject to a harmonised norm IEC 60947-5-2. All the main important technical data and features are stated within this norm. Meeting these standards makes life easy for the user with regard to selection and replacement of sensors. NormLine sensors guarantee a free trade in the common market, ensure excellent quality, and reduce down time in industry. All these demands are met by NormLine sensors, the recommended types are ideal for standard applications, meeting international standards giving the user off the shelf items and latest technology for an economic price. Where the application demands more from the sensor, such as use in high temperature areas, ATEX applications, pharmaceutical, chemical or food industry, please refer to our high performance standard series of high-tech capacitive sensors.

Housing materials
The application of the housing materials used is based on the technical specifications of the material and of the manufacturer. Even though RECHNER Sensors have far-reaching application experience concerning the use of different housing materials, the customer is responsible for checking in each case that the housing material is suitable for the application.

Cable
For the standard models PVC- or PUR-cable are used. One has to take into consideration that the cable should not be moved with ambient temperatures below -5°C. PVC is not suitable for use in applications with oil-based liquids or with UV-radiation. PUR is not suitable for continuous contact with water. For special application areas silicone or PTFE cables are available.

Minimum sensing distance / Smin
The minimum possible sensing distance, which can be adjusted by potentiometer and which can be used effectively in practical applications with reference to a medium with er > 80.

Maximum sensing distance / Smax
The maximum possible sensing distance, which can be adjusted by potentiometer and which can be used effectively in practical applications with reference to a medium with er > 80. The sensors should only be used under constant ambient conditions, such as constant temperature, no humidity, and no deposits on the active face of the sensor.

Nominal sensing distance / Sn
The characteristic value of a proximity sensor, without consideration of production tolerances and variations due to temperature and voltages.

Real sensing distance / Sr
The sensing distance determined at +20 °C and rated voltage. Here the series variance is taken into consideration. Variation max. 10 % +/- of Sn.

Reduction factors
For materials other than metals (e.g. FE 360 or ST 37, Al, Cu) or water, the reduction factors shown in the table on page 6 of the KAS catalogue should be taken into consideration.

Series- and parallel connection
It is possible to connect the proximity sensors in series or parallel. When considering this it must be taken into account that the voltage drops are added for series connection and the residual voltages for parallel connection. Under these circumstances it is advisable to operate a maximum of three sensors in a corresponding circuit.

Repeat accuracy of the switching point
The variation of the switching point of two successive measurements at constant ambient conditions.

Frequency of operating cycles
The maximum damping and un-damping cycles of the proximity sensor within one second. To ascertain the frequency of operating cycles a pulse / break ratio of 1 : 2 is used as a basis, at Sn 1/2.

Switching hysteresis
The difference between the switch-on and switch-off point of a proximity sensor, when approaching or moving away from the standard measuring plate.

Enclosure rating
IP 65: Protection against contact with voltage-carrying parts, protection against ingress of dust and water jet. IP 67: Protection against contact with voltage-carrying parts, protection against ingress of durst and protection against ingress of water when the equipment is immersed in water, up to 1 m depths and for a period of 30 minutes.

Temperature variation
The drift of the switching point if the ambient temperature changes.

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