ATEX-approved level switch
Baumer’s multi-purpose LBFS level switch is available in three ATEX configurations, which enable safe level detection in explosive gaseous and dusty atmospheres, typically found in the chemical, pharmaceutical, or food industries. Baumer uses a highly specialized protective design for the ATEX versions of the LBFS. Thanks to this, versions Ex ta for dust (zones 20, 21 and 22) and Ex nA for gas (zone 2) can be used without a Zener barrier because the housing itself already provides all the necessary protection. This is very cost-effective because sensors for hazardous areas usually require a Zener barrier. The ATEX certifications cover zones 0, 1 and 2 (gas) as well as zones 20, 21 and 22 (dust). Quick installation and easy use is also ensured for version Ex ia for gas (zones 0 and 1). For this version, Baumer provides the ready-for-use isolation module PROFSI3 LS which is specially designed for use with Baumer’s level switches LBFS and LFFS. This isolation module saves users the time and effort of selecting and configuring an additional Zener barrier to operate the sensor.
The Profsi3 LS can operate with dc voltages from 22 V dc to 120 V dc as well as ac voltages from 90 V ac to 253 V ac. The LBFS is based on frequency-sweep technology, a method particularly suitable for precisely measuring the level of solids and powders. As the processing of these materials often creates explosive dust, the new ATEX versions open a wide range of new applications valuable for LBFS users in the chemical and pharmaceutical industries.
Industries like oil and gas, energy production and milling will also find this new level switch convenient. The ATEX versions of the LBFS level switch can easily be adapted to the needs of very diverse applications thanks to a wide range of available process connections including G½”, G3/4”, G1”, G½” hygienic, G½” for reverse assembly, M18x1, and G3/4 NPT.
The Profsi3 LS interface shields the safe area from the hazardous area through galvanic isolation. The level detected within the hazardous area is transmitted to the safe area through a single-pole double-throw relay.
The Baumer Group
– Edited by Chris Vavra, Control Engineering, www.controleng.com