Series TFLS Tuning Fork Level Switch

Brand: Dwyer Instruments, LLC

Series TFLS Tuning Fork Level Switch is ideal for level control of powders and fine grained solids, especially those with a low bulk density.

The TFLS incorporates a piezoelectric crystal that vibrates the fork at its natural frequency. When the fork comes in contact with material, the vibration is dampened and the switch changes state. As the fork becomes free of material, the switch changes back to its normal state.

Featured in the TFLS is user-selectable fail-safe operation of the contacts. Unit is not affected by vibration from conveying systems, motors, or the movement of material. It can be mounted in any position and is available with factory built extensions for mounting on the top of the storage vessel.

Series TFLS is easy to use, with no calibration required and with no mechanical moving parts there is no routine maintenance required.

The TFLS is unaffected by the dielectric constant of the sensed material, making it superior to a capacitance level switch for applications where the dielectric constant is too low, where there is more than one material being used in one vessel, and when material moisture content can change.

The level switch is also good for applications when the bulk density is too low for a rotating paddle level switch. It can also detect granular material submerged in liquids of low viscosity, for example sand, gravel, or polyester chips in water.
Features
  • Status indication with external LED switch indicator, and internal indicators for normal and alarm status
  • No calibration required for quick and easy installation
  • No mechanical moving parts with no routine maintenance required
  • Unaffected by the dielectric constant of the sensed material, making it superior to a capacitance level switch for applications where the dielectric constant is too low, where there is more than one material being used in one vessel, and when material moisture content can change
  • Vibrating fork design is ideal for low bulk density and low dielectric constant products, detecting products down to 1.8 lb/ft3 (30 g/l)
  • Ideal for applications where the bulk density is too low for a rotating paddle level switch
  • Adjustable sensitivity can be set to ignore lighter bulk density products and only detect heavier products, such as sand, gravel, or polyester chips in water
  • Unit is not affected by vibration from conveying systems, motors, or the movement of material
  • Mounted in any position and is available with factory built extensions for mounting on the top of the storage vessel
  • Failsafe setting with output switch that can be set for NO or NC condition on loss of power
  • Time delay prevents false alarms from material surges
  • Universal power supply yields one model which works with 90 to 265 Vac and 24 Vdc

Specifications

Ambient Temperature Range

  • -20° to 60° C (-4° to 140° F)

Conduit Connection

  • 3/4” NPT Female

Consumption

  • 4 VA

Electrical Connectors

  • Screw Terminal

Electrical Rating

  • 5 A at 230 Vac

Enclosure, Body Material

  • Aluminum Powder-Coated

Environmental Protection

  • IP66
  • NEMA 4X
  • Weatherproof

Indication

  • Green LED: Internal
  • Red LED: Internal & External

Media

  • Liquids & Gases

NPT Connection

  • 1-1/2” NPT Male
  • 3/4” NPT Female

Operating Time

  • 2 to 20 seconds

Power Requirement

  • 24 Vdc
  • 50/60 Hz
  • 90-265 Vac

Process Temperature

  • -20° to 80° C (-4° to 176° F)

Sensitivity

  • 1.8 lbs/ft³ (30 G/l)

Supply Pressure

  • psi: 145 (kPa: 1,000, bar: 10)

Switch Type

  • SPDT

Wetted Materials

  • 316 Stainless Steel

  • Lime
  • Styrofoam
  • Tobacco
  • Dry Cereals
  • Sugar
  • Animal Feed
  • Milk Powder
  • Flour
  • Insulation
  • Cement
  • Paper Shavings
  • Plastic Granules
  • Sawdust
  • Carbon Black
  • Light Fibers
  • Detergent Powders
  • Dyes
  • Chalk
  • Silica
  • Sand
  • Wood Chips
  • Chemical Processing
  • Pulp and Paper Processing
  • Mining
  • Food and Beverage

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