Whether in chemical plants or in the oil and gas industry—vibration limit switches reliably detect the level of liquids. In this way, minimum or maximum values in tanks can be detected or pumps can be protected from running dry. With Vibracon LVL-M3 and -M4, Pepperl+Fuchs offers two new series of vibration limit switches that can be used worldwide in potentially explosive atmospheres due to ATEX and IECEx approvals. While the LVL-M3 variant is the ideal choice for standard applications, the LVL-M4 variant is also suitable for applications with increased safety requirements up to SIL 3. A Bluetooth® interface enables intelligent remote diagnostics and convenient proof tests.
The mode of operation of vibration limit switches is as simple as it is reliable: The vibrating fork on the sensor is set in vibration by a piezoelectric element. As soon as a liquid comes into contact with the fork, a change in frequency occurs. In this way, the limit level is detected. The vibration limit switches from Pepperl+Fuchs reliably distinguish between foam, air bubbles or deposits and the medium to be detected. At the same time, they are unaffected by changing media properties and therefore reliably detect the level in any application.
Since the Vibracon vibration limit switches have no mechanical moving parts, they are characterized by a long service life. The plug-and-play principle means that no calibration to different media is necessary, so the sensors can be put into operation quickly and easily. They are operated via push buttons and DIP switches on the electronics module.
In addition to the compact versions, variants with tube extensions up to 6 m are also available. This allows the vibration limit switches to be used in large tanks without any problems. An extensive selection of process connections, including a tri-clamp for hygienic applications, enables flexible adaptation to different environments. In addition, a wide variety of electronic modules is available so that the right connection can be found for any process control system.
The LVL-M3 variant is suitable for universal use in all liquids that can be pumped. The vibration limit switch withstands process temperatures of -40 °C ... +150 °C and process pressures up to 40 bar.
The LVL-M4 variant is the ideal solution for applications with increased safety requirements: The vibration limit switch can be used for safety applications up to SIL 3 in accordance with IEC/EN 61508. In addition, the device withstands process temperatures of -50 °C ... +150 °C as well as process pressures up to 100 bar. A second line of defense ensures that no medium can escape into the atmosphere even in the event of damage.
As a special highlight, the LVL-M4 variant has a Bluetooth® interface that can be used to connect the device to the P+F Level App. This mobile app not only enables easy configuration of the sensor and convenient proof testing. It additionally offers status and fault indication as well as integrated technology for corrosion detection, enabling predictive maintenance.
With the LVL-M4 variant, proof tests can be performed not only via the P+F Level App, but also externally via an integrated test button or via a test magnet. In addition, status and fault indications are displayed directly on the device via an LED module.