In the last ten years, the use of industrial Ethernet technology in industrial and process automation solutions has grown strongly. However, the "traditional" field bus still represents 70% of the total. Profibus remains the first choice among these after more than 20 years on the market and 47.4 million nodes installed (as of end-2013), accounting for more than 20% – even in new installations.
The main advantage of using solutions with a Profibus protocol is that they can be integrated into complex systems with long communication distances where data needs to be sent quickly and securely. Moreover, Gefran's quality standards are reflected in high levels of reliability and durability, extremely precise readings – as demonstrated by a nonlinearity of 0.01%/FS – and maximum thermal drift of 20 ppmFS/°C.
Gefran's new MK4P/IK4P models have a Profibus DPV0 interface on RS485, in accordance with IEC 61158. They are available in a profile (MK4-P) or rod (IK4-P) version (50 - 4000 mm stroke). In the profile version, sliding or floating cursors may be used, providing greater flexibility of installation. In the rod-style version, ring magnets are available for installation in cylinders and floating magnets can be used for level measurement.
The transducer can manage from one to four cursors on a single sensor for precise and fast position readings. Information is also available on the sensor's condition and on errors in position reading (condition of the magnet). There is a choice of options for the offset of each magnet and the direction of measurement (forward/back).
The transducer is linked by an M8 4-pole connector which feeds two M12 5-pole connectors used to connect the bus. This means the device can be configured using portable programmers without the transducer having to be connected to the bus network.
All parameters, including the resolution, can be configured via software using a class 2 master. The structure and format of the configuration parameters are described in the GSD file, which can be downloaded from the website. PNP-1 is provided as an accessory and can be used to program the MK4P/IK4P node number within the network – if there is no class 2 master available.