When the level of the material in silo or hopper rises and covers sense electrode the switch operates. When there is coating on electrode, no current flows between sense and ground. The coat guard electrode is driven with the same potential and phase as sense. In this circuit, additional coat guard electrode is added which is insulated from sense as well as ground electrode. The coat guard circuit is added to overcome this problem. COAT GUARD CIRCUIT:Normal capacitance type switches may not perform if the process material builds up on the probe. The level switch is immune to the material built-up on the probe and material bridging between the probe and hopper wall. The RF Admittance type, point level switch, designed with special sensing probe, using special shield coat-guard circuit and three element probe. Special Coat-guard amplifier is incorporated in the circuit, which will ignore the effect of deposition. Such changes caused by increase in level is amplified and used to actuate the relay. RF environment absorption changes (Electrical Loss) around the electrode are reflected on the changes of generator supply current. The electronic unit generates a sinusoidal wave, applied to the electrode creating a field around it. Interface detection OPERATING PRINCIPLE:The RF Level switch operates on the basis of RF absorption.Detection of level of conducting, non conducting, organic, inorganic almost all materials.Level sensing of sticky material like slurry, mud and sticky material (Consult factory). Level detection of pellets, granules, powders, chips and flakes.Detection of top and bottom levels of coal bunkers.Detection of levels of solids, liquids granules food grains and powders,.Detection of chute blockage in feeding hoppers: CHUTE BLOCK SWITCH.SMARTsaa offers entirely new range of RF admittance type Level Switches for measuring level of powder, granules and bulk solids like fly ash, coal, food grains, chemicals, slurry in hoppers and silos. Operating PressureĬhute Block Detection,Level Switch,Chute Plug Detection Particle Size: up to 30 mm and a density of 0.3 to 2.5 g/cm3DETAILS REQUIRED: Material to be sensed, Particle size, Bulk Density, Mounting position (Dimensions and drawing of hopper), Diaphragm Material, Max.Diaphragm Material: SS / Neoprene Rubber.Pressure for detection : Approx 2 N min.O/P: 1 C/O relay contact rated for 10 Amp resistive at 230 V AC.Enclosure: Cast Al, ABS Plastic, IP 40.Over-Pressure Protection for screw conveyorSPECIFICATIONS:.Ideally suited when vessel size or internal clearance is limited or where protrusion into a vessel is not acceptable.The contact of limit switch is used for control action.FEATURES: Can be used as Chute Block Device OPERATING PRINCIPLE: The pressure of the product on the membrane operates a limit switch inside the switch compartment.Detects bin overflow and maintain a pre-determined material level.Boot level detection of bucket elevator.Sensing clogging of material on screw conveyor.Type 61 is installed directly at the switching point, 62 has an extension cable (max 80 m) and 63 is the version with extension tube (max 6 m).SMARTsaa offers Diaphragm / Membrane Level switch for measuring level of free flowing and dry material like food grains and powders and bulk goods. APPLICATION: VEGAWAVE for up to 10 mm grain size, above that, VEGAVIB. Vibrating level switches are used as overfill protection or empty alarm in bulk solids, which can be either in granulate or powder form. If the vibrating probe comes into contact with the measured product, the oscillation rate changes and the vibrating level switch outputs a switching command. The basis of point level detection with vibrating level switches is a vibrating rod or vibrating fork. A downstream device can be actuated directly with this switching signal (e.g. It provides a switching signal on its own. it can be operated without external evaluation. The instrument is connected with standard cable. The instrument only has to be mounted in such a way that the vibrating element is at the height of the desired switching point. The level switch can be installed in any position. The switching point can be up to 6 m away from the process fitting. VEGASWING 63 is the version with extension tube. VEGASWING 61 is mounted directly at the switching point Vibrating level switches are used as overfill protection or empty alarm. If the vibrating probe comes into contact with the medium, the oscillation rate changes and the vibrating level switch outputs a switching command. The basis of point level detection with vibrating level switches is a tuning fork, i.e.
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