One of key features of the versatile Multidrive 6185 tractor is its Pentronic 5-function, all-wheel steering system which includes highly reliable Novotechnik RFC4800 'touchless technology' non-contacting angle sensors supplied by Variohm EuroSensor.
The 2 or 4 wheel steering system, with independent axle control and advanced features that prevent crop damage and soil compaction, means that the Gloucestershire built vehicle can carry and haul heavy loads as well as perform meticulous spraying and spreading tasks - making the adaptable 6185 suitable for all areas of farming.
For Multidrive, a part of Kellands Agricultural Ltd, the reliability and durability of equipment used on the 6185 is paramount and they worked closely with Variohm to ensure that these critical position feedback components met their stringent standards. The tractor is used all over the world and sees wide variations in temperature and humidity and needs to perform faultlessly, regardless of the terrain and weather conditions.
The RFC4800 angle sensor provides a 12-bit resolution (0.09 degrees) analogue output in a compact two-part design comprising a position marker with an encapsulated magnet that is attached to the customer's shaft, and a physically separate sensor which is encased in a robust IP69 rated sealed housing made from high-grade and temperature resistant plastic.
As a bearing system is not used, installation is straightforward and removes the need for mechcanical couplings eliminating the additional problems of load applied to the shaft of the existing sensor. Suited to space restricted envelopes the transmissive properties between magnet and sensor means that operation can be made through non-magnetic materials. Furthermore, as the position output is absolute and the angular relationship between magnet and sensor is fixed, there is no need for elaborate calibration on set-up or a need to reset the steering position when restoring power to the vehicle.
A choice of three models is available for supply voltages of 5 VDC, 12 VDC or 12/24 VDC. Optional output formats include 0 - 10 VDC, 0.5 - 4.5 VDC, a ratiometric voltage based upon a pre-calibrated percentage of the input, and 4 - 20 mA.The standard electrical angle is 360 degrees but optional 30 to 360 degree specials are available as redundant output versions and IP67 rated housings.
The touchless non-contacting technology used in the RFC4800 series offers an effectively unlimited life for the mechanical parts and the 50000 hour MTBF quoted figure for the electronics will suit ultra long life applications. Equally impressive are the agricultural vehicle standard specifications for shock and vibration.