Powder & Bulk Level Sensors

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Overview

DBOB – Continuous Level Measuring SystemFCLS – Flush Capacitance Level SwitchPLS2 – Paddle Level SwitchVRLS – Vibrating Rod Level SwitchTFLS2 – Compact Tuning Fork Level SwitchCTF – Mini Tuning Fork Level Switch

DBOB - Introduction

Continuous measurement of level or volume in silos, tanks, or hoppersUser programmable to output either a height signal or a volumetric signal based on the vessel geometryFlat tape line limits tangles and material building in housingTwo 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 NPTAccuracy: ±1.5% FSOutput: Linear 0 to 5 VDC and 4 to 20 mAEnclosure: IP66

PLS2 - Introduction

Point level switchDetects level when bulk material builds up and stops the rotating paddlePurchase by power requirement

PLS2 - Key Specifications

Wetted Materials: 304 SS, 303 SSNBR, and AluminumSwitch Type: SPDT micro switchProcess Connection: 1-1/4" male NPTPower Requirement: Select by model number: 115 VAC, 230 VAC or 24 VDCEnclosure Rating:

IP66Rated for Class II & III, Div. 1, Group E, F, G.

FCLS - Introduction

Point level switchFor liquids and bulk solidsNo moving parts

FCLS - Key Specifications

Wetted Materials: 304 SS, PTFE Enclosure Rating: IP65Switch Type: SPDTPower Requirements: 110-220 VACProcess Connection: 2.5" - x 5 kg/cm2 JIS flange

TFLS2 - Introduction

Level switch for low density bulk solids and liquidsUses a vibrating tuning fork to detect levelCompact probe

Model TFLS2

TFLS2 - Key Specifications

Wetted Materials: 316 L SSSensitivity: Min. bulk density 70 g/l, (4.4 lb/ft3)Process Connections: 1" male NPTPower Requirement: 20 to 250 VAC, 50/60 HzEnclosure Rating: IP65

CTF - Introduction

Level switch for low density bulk solids and liquidsUses a vibrating tuning fork to detect levelCompact 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 NPTPower Requirement: 12 to 55 VDCEnclosure Rating: IP65

VRLS - Introduction

Level switch for powders and bulk solidsUses a vibrating rod to detect levelAdjustable for detection ranging from large granular material to small powders with low bulk densities

VRLS – Key Specifications

Wetted Materials: 304 SSSensitivity: Min. bulk density of 320 kg/m3 (20 lb/ft3)Power Requirement: 20 to 250 VAC/VDCProcess Connections: 1" male NPTEnclosure Rating: IP65Switch Type: SPDT

Application

When to use each design:

Paddle:Lowest costBulk materials onlyBest for high density material

Capacitive:Measurement based on di-electric characteristics of the material, not densityBest for low density, or liquid materials

Tuning Fork:Measurement based on material densityBest for lower density, low di-electric constant materials

Vibrating Rod:Measurement based on material densityUsed where tuning forks are affected by material buildup

Application

LimeTobaccoDry cerealsSugarAnimal feedMilk powder

FlourInsulationCementPaperPlastic granulesDetergentsDyes

ChalkFly AshFumed Silica Carbon BlackStyrofoamCorkSawdust

Typical Bulk Materials:

Application

Mounting Considerations

Tuning Forks

Application

Dust Collection

Application

Dust CollectorThe 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 PlantsBulk level switches are typically mounted at the top of the silo for high and low level indicationThe PLS2 is a rugged and reliable switch for monitoring gravel and sand

ApplicationsPneumatic Conveying

Applications

Dilute Phase Pneumatic ConveyingDilute 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