Powder & Bulk Level Sensors The materials included in this compilation are for the use of Dwyer Instruments, Inc. potential customers and current employees as a resource only. They may not be reproduced, published, or transmitted electronically for commercial purposes. Furthermore, the Company’s name, likeness, product names, and logos, included within these compilations may not be used without specific, written prior permission from Dwyer Instruments, Inc. ©Copyright 2014 Dwyer Instruments, Inc.

Overview DBOB – Continuous Level Measuring System FCLS – Flush Capacitance Level Switch PLS2 – Paddle Level Switch VRLS – Vibrating Rod Level Switch TFLS2 – Compact Tuning Fork Level Switch CTF – Mini Tuning Fork Level Switch

DBOB - Introduction Continuous measurement of level or volume in silos, tanks, or hoppers User programmable to output either a height signal or a volumetric signal based on the vessel geometry Flat tape line limits tangles and material building in housing Two programmable relays

DBOB - Key Specifications Wetted Materials: GFM-1XXX: Anodized aluminum, brass, and fluoroelastomer GFM-2XXX: 316 SS and fluoroelastomer Process Connection: 1-1/2" male NPT Accuracy: ±1.5% FS Output: Linear 0 to 5 VDC and 4 to 20 mA Enclosure: IP66

PLS2 - Introduction Point level switch Detects level when bulk material builds up and stops the rotating paddle Purchase by power requirement

PLS2 - Key Specifications Wetted Materials: 304 SS, 303 SS NBR, and Aluminum Switch Type: SPDT micro switch Process Connection: 1-1/4" male NPT Power Requirement: Select by model number: 115 VAC, 230 VAC or 24 VDC Enclosure Rating: IP66 Rated for Class II & III, Div. 1, Group E, F, G.

FCLS - Introduction Point level switch For liquids and bulk solids No moving parts

FCLS - Key Specifications Wetted Materials: 304 SS, PTFE Enclosure Rating: IP65 Switch Type: SPDT Power Requirements: VAC Process Connection: 2.5" - x 5 kg/cm2 JIS flange

TFLS2 - Introduction Level switch for low density bulk solids and liquids Uses a vibrating tuning fork to detect level Compact probe Model TFLS2

TFLS2 - Key Specifications Wetted Materials: 316 L SS Sensitivity: Min. bulk density 70 g/l, (4.4 lb/ft3) Process Connections: 1" male NPT Power Requirement: 20 to 250 VAC, 50/60 Hz Enclosure Rating: IP65

CTF - Introduction Level switch for low density bulk solids and liquids Uses a vibrating tuning fork to detect level Compact size and DIN connection

CTF - Key Specifications Wetted Materials: 304 SS and 316L SS Sensitivity: Min. bulk density 70 g/l, (4.4 lb/ft3) Process Connections: 1" male NPT Power Requirement: 12 to 55 VDC Enclosure Rating: IP65

VRLS - Introduction Level switch for powders and bulk solids Uses a vibrating rod to detect level Adjustable for detection ranging from large granular material to small powders with low bulk densities

VRLS – Key Specifications Wetted Materials: 304 SS Sensitivity: Min. bulk density of 320 kg/m3 (20 lb/ft3) Power Requirement: 20 to 250 VAC/VDC Process Connections: 1" male NPT Enclosure Rating: IP65 Switch Type: SPDT

Application When to use each design: Paddle: Lowest cost Bulk materials only Best for high density material Capacitive: Measurement based on di- electric characteristics of the material, not density Best for low density, or liquid materials Tuning Fork: Measurement based on material density Best for lower density, low di- electric constant materials Vibrating Rod: Measurement based on material density Used where tuning forks are affected by material buildup

Application Lime Tobacco Dry cereals Sugar Animal feed Milk powder Flour Insulation Cement Paper Plastic granules Detergents Dyes Chalk Fly Ash Fumed Silica Carbon Black Styrofoam Cork Sawdust Typical Bulk Materials:

Application Mounting Considerations Tuning Forks

Application Dust Collection

Application Dust Collector The flush capacitance level switch can be used for plug protection in the base of the dust collector or as a high level switch in the collection hoppers

Application Cement Mixing Plants Bulk level switches are typically mounted at the top of the silo for high and low level indication The PLS2 is a rugged and reliable switch for monitoring gravel and sand

Applications Pneumatic Conveying

Applications Dilute Phase Pneumatic Conveying Dilute phase pneumatic conveying is a high velocity low pressure system (less than 15psi/1 bar) The paddle level switch (Series PLS2) is an inexpensive level switch for the receiving bins in a dilute phase system

Applications Dense Phase Pneumatic Conveying Dense Phase Pneumatic Conveying is a low velocity high pressure system (greater than 15psi/1 bar) The vibrating rod level switch is used as a high level switch in the transporter and the receiving bins