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Vibrating Rod Level Sensors for Light Bulk Solids

BinMaster vibrating rod level sensors provide dependable point level detection for powders, flakes, granules, and bulk solids. These sensors are ideal for high-level alarms, low-level alerts, or plugged chute detection in bins, silos, and hoppers.

 

Vibrating probes are especially effective for lightweight, fluffy powders and flakes with bulk densities as low as 1.25 lb./ft.³ where other technologies may struggle to detect the presence of material.

Reliable Detection in Powders & Flakes

BinMaster's Selection of Vibrating Probe Sensors

BinMaster offers a broad selection of vibrating probes.

These sensors provide reliable performance in materials such as Styrofoam®, plastic pellets, sawdust, carbon black, chalk, flour, and other lightweight bulk solids.

  • Sword-blade vibrating rods
  • Round vibrating rods
  • Vibrating forks
  • Rigid and flexible extensions
  • High-temperature models
  • Sanitary designs
  • Mini vibrating probes for small vessels

VRX sensors can be mounted at the top, side, or cone of a bin or vessel to measure level of lightweight bulk materials

How Vibrating Probe Level Sensors Work

Vibrating rod level switches operate using a piezoelectric crystal element that causes the sensing blade or rod to vibrate at its natural frequency.

When the probe is uncovered, the vibrating element oscillates freely. But when material contacts—or covers—the probe:

  1. The vibration becomes damped
  2. The sensor electronics detect the change in vibration frequency
  3. The sensor triggers a relay output, indicating a covered condition

When the material falls away from the probe, vibration resumes, and the sensor returns to an uncovered state.

This simple operating principle makes vibrating rods highly reliable and resistant to dust, buildup, and changing material characteristics.


VRX Series Vibrating Probe Features

VRX vibrating rod sensors feature a buildup-resistant, sword-shaped blade

Buildup-Resistant Blade


The unique sword-shaped blade is designed to prevent buildup and false alarms.

 

The slender blade encourages materials to flow past the probe to ensure reliable detection.

 

Unlike tuning fork sensors, the single-blade design eliminates bridging between forks, which can occur with certain materials.

VRX level sensors include adjustable sensitivity settings for detection of  lightweight bulk materials

Adjustable Sensitivity Settings


A switch located inside the housing of the VRX21, VRX31, VRX41, and VRX51 allows operators to adjust sensitivity.

 

Position 1 – High Sensitivity detects extremely light or fluffy materials.

 

Position 2 – Low Sensitivity is used for heavier materials and prevents false signals from clinging.

Ask your BinMaster Sales Manager for the latest on hazardous location approvals for VRX sensors

Hazardous Location Approvals


Hazardous location approvals are coming soon for the VRX series.

 

Contact your local BinMaster Sales Manager for the latest updates on location approvals.


Vibrating Blade Sensors

BinMaster’s sword-blade vibrating rods are designed for detecting lightweight materials.

Their wide, flat blade creates stronger vibration and higher sensitivity for detecting low-density powders and flakes.

  • Detects materials with bulk densities as low as 1.25 lb./ft.³
  • Buildup-resistant blade design
  • Prevents bridging associated with fork designs
  • Ideal for powders, flakes, and aerated materials

Typical Materials: Styrofoam®, sawdust, carbon black, chalk, flour, and plastic flakes and pellets

Models: VRX21, VRX31, VRX41, VRX51, VRX61, and VRX71


Vibrating Rod and Vibrating Fork Sensors

Round vibrating rods use a single stainless-steel rod that vibrates until material contacts the probe.

When vibration is damped by material, the sensor triggers a switch.

  • Rugged one-piece rod construction
  • Suitable for powders and granules
  • Reliable operation in dusty environments
  • Models: VR-90, VR-92, and VR-93

Vibrating forks use two vibrating tines that oscillate together. When material surrounds the forks, vibration stops and the sensor signals a covered condition.

  • Best suited for fine powders or granulated materials that will not bridge between tines
  • Ideal for sanitary environments
  • Models: VF-90, VF-92, and VF-93

Vibrating Probe Installation Options

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Top mounting for high-level detection

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Side mounting for high-, mid-, or low-level alerts

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Cone mounting for low-level or empty detection

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Plugged chute detection


Mounting Plates

Powder-coated carbon steel mounting plates are available for flat or angled bin roofs.

 

Available mounting angles for angled roofs include , , 10°, and 30° plates.

 

Side or cone installations typically use a 0° mounting plate.


Custom-Manufactured Sensors for Your Application

While the VRX21 standard vibrating rod is always in stock, BinMaster can customize vibrating probes for specific applications.

 

BinMaster’s in-house machining and assembly allows each sensor to be configured for the specific vessel and material. Custom options include:

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Extended insertion lengths, for thick bin walls or extended level detection

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Flexible cable probes, for use where a rigid probe may be damaged

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Sediment detection probes, for settled material in liquids

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Remote electronics housings, to distance electronics from heat


VRX21, VRX41, and VRX51 models: standard option, rigid pipe extended sensor, and flexible steel-rope cable vibrating probe

Vibrating Probe Models

The VRX21 is BinMaster's standard in-stock model with a 7.5-inch insertion length.

Typical uses include top- or side-mounted level detection, plugged chute detection, and low-level detection in vessel cones.

Rigid Extended Probes

The VRX41 can be extended from 13 inches to 13 feet using galvanized pipe, stainless-steel pipe, or sanitary pipe extensions.

Level detection for light, medium, and heavy materials.

Flexible Extended Probes

The VRX51 uses a steel-rope reinforced cable extension. Extension lengths range from 19 inches to 19.5 feet.

Flexible probes resist damage from falling material and are custom-built to customer specifications.


The VRX31 vibrating rod level sensor is designed for sanitary processing environments where clean-in-place sensors are required

Vibrating Rods for Challenging Applications

Sanitary Processing

The VRX31 sanitary vibrating rod is designed for food and pharmaceutical processing. It is suitable for clean-in-place systems.

Features include a 2" sanitary stainless-steel fitting and compatibility with Tri-Clamp connections. Optional stainless-steel extensions are available up to 6.56 feet.

Remote Electronics

Remote electronics allow the sensing probe to be separated from the electronics housing. Remote kits include a mounting plate and 20 feet of cable.

This option is useful when high vibration or high process temperatures are present and installation space is limited. Remote electronics are available for:

  • Standard VRX probes
  • Sanitary models
  • Rigid extended probes
  • Flexible extended probes

VRX61 and VRX71 vibrating probes: high-temperature point level sensors with an option for extended or standard probe length

Probes for High-Temperature Applications

The VRX61 and VRX71 are designed for high temperature applications up to 482°F (250°C).

The VRX61 has a 7.25-inch probe, while the VRX71 can be extended up to 13.3 feet. More features include:

  • Raw-cast aluminum housing
  • Insulated extension tube
  • Optional remote electronics

Compact Vibrating Rods for Small Spaces

For small vessels, compact hoppers, or tight installations, BinMaster offers miniature vibrating rods: the CVR-625 and CVR-600. Features include:

  • Approximately 6-inch insertion length
  • Compact sensor body
  • Simple installation

In regard to mounting compact vibrating sensors, the CVR-625 has a 1¼" NPT connection, whereas the CVR-600 has a 1" NPT connection.


Special-Purpose Probes

VR-21 and VR-41 SED vibrating probe models for detection of settled solids

Sediment Detection


The VR-21 SED and VR-41 SED vibrating probe detects settled solids beneath liquids in tanks.

 

Rigid extensions for the VR-41 SED are available from 13 inches to 13 feet.

VR-90 vibrating rod level sensor for level detection in coarse bulk solid materials

Round Rod for Coarse Solids


The VR-90 vibrating rod features a round stainless-steel rod designed for coarse materials.

 

It is also used when material type frequently changes in a vessel. Hazardous location approvals are available.

VF-90 vibrating fork sensor to prevent bridging or clinging in bulk powders and fine solids

Vibrating Fork Sensors


The VF-90 vibrating fork provides universal point level detection for powders and fine solids.

 

Applications include construction materials, feed ingredients, and plastic powders and flakes.


Stainless-steel housing options allow use in food or pharmaceutical environments.


Vibrating probe level sensors operate best in fluffy powders, aerated materials, or lightweight pellets where high sensitivity level sensing is a must

When to Use Vibrating Probe Sensors

Because vibrating rods detect changes in vibration rather than dielectric properties, they provide reliable performance in low-density materials that capacitance probes or rotary paddles may not detect consistently.

Use vibrating rod sensors when:

  • Measuring very light, fluffy, or aerated materials
  • Bulk density is as low as 1.25 lb./ft.³
  • Materials include powders, flakes, or foam-like solids
  • The process requires high-sensitivity detection
  • Managing materials like Styrofoam®, carbon black, plastic flakes, sawdust, chalk, or flour

Opting for Another Point Level Technology

Different point level technologies perform best in different material types.

Use rotary level sensors when:

  • Bulk solid materials are between 5 and 100 lb./ft³
  • Bulk density of material is moderate to high
  • Simple mechanical detection is acceptable

Use capacitance probes in:

  • Materials with stable dielectric properties
  • Conductive or non-conductive liquids
  • Solids including powders and granules

VRX21 VRX31 VRX41 VRX51 VRX61 VRX71
Minimum Material Density 1.9 lb./ft.³ (30 g/liter) 1.9 lb./ft.³ (30 g/liter) 1.9 lb./ft.³ (30 g/liter) 1.9 lb./ft.³ (30 g/liter) 1.9 lb./ft.³ (30 g/liter) 1.9 lb./ft.³ (30 g/liter)
Ambient Temperature (Electronics) -4°F to +140°F (-20°C to +60°C) -4°F to +140°F (-20°C to +60°C) -4°F to +140°F (-20°C to +60°C) -4°F to +140°F (-20°C to +60°C) -4°F to +140°F (-20°C to +60°C) -4°F to +140°F (-20°C to +60°C)
Process Temperature (Probe) STD probe: -4°F to +176°F (-20°C to +80°C);
HT probe: -4°F to +284°F (-20°C to +140°C)
-4°F to +176°F (-20°C to +80°C) -4°F to +176°F (-20°C to +80°C) -4°F to +176°F (-20°C to +80°C) -4°F to +500°F (-20°C to +260°C) -4°F to +500°F (-20°C to +260°C)
Conduit Entries 3/4” NPT 3/4” NPT 3/4” NPT 3/4” NPT 3/4” NPT 3/4” NPT
Enclosure Material Die-cast aluminum; USDA-approved powder coat finish Die-cast aluminum; USDA-approved powder coat finish Die-cast aluminum; USDA-approved powder coat finish Die-cast aluminum; USDA-approved powder coat finish Die-cast aluminum; USDA-approved powder coat finish Die-cast aluminum; USDA-approved powder coat finish
Enclosure Rating NEMA Type 4X NEMA Type 4X NEMA Type 4X NEMA Type 4X NEMA Type 4X NEMA Type 4X
Power Supply 24 VDC or 115/230 VAC 24 VDC or 115/230 VAC 24 VDC or 115/230 VAC 24 VDC or 115/230 VAC 24 VDC or 115/230 VAC 24 VDC or 115/230 VAC
Relay Output Rating DPDT contacts; 5 Amps 250 VAC DPDT contacts; 5 Amps 250 VAC DPDT contacts; 5 Amps 250 VAC DPDT contacts; 5 Amps 250 VAC DPDT contacts; 5 Amps 250 VAC DPDT contacts; 5 Amps 250 VAC
Time Delay Configurable Configurable Configurable Configurable Configurable Configurable
Mounting 1-1/4” NPT or 1-1/2” NPT 2” Tri-clamp 1-1/2” NPT 1-1/2” NPT 1-1/2” NPT 1-1/2” NPT
Approvals Ordinary locations Ordinary locations Ordinary locations Ordinary locations Ordinary locations Ordinary locations
VR-90 VF-90
Process Temperature -58° to +482°F (-50° to +250°C) -58° to +482°F (-50° to +250°C)
Process Pressure -1 to +25 bar/-100 to +2500 kPa (-14.5 to +363 psig) -1 to +16 bar/-100 to +1600 kPa (-14.5 to +232 psig)
Ambient Temperature -40°F to +176°F (-40°C to +80°C) -40°F to +176°F (-40°C to +80°C)
Bulk Density ≥0.008 g/cm³ (0.0003 lb./in.³) ≥0.02 g/cm³ (0.0007 lb./in.³)
Process Fitting Thread from G1½, 1½ NPT; Flanges from DN 50, 2” Threaded 1.0”, 1.25”, and 1.5” NPT; 2.0” flange; 2.0” clamp
Power 20 to 253 VAC, 50/60 Hz, 20 to 253 VDC 20 to 253 VAC, 50/60 Hz, 20 to 253 VDC
Signal Output Relay (DPDT), transistor (NPN/PNP), two-wire output, contactless electronic switch Relay (DPDT), transistor (NPN/PNP), two-wire output, contactless electronic switch
Switching Relay When being covered: 0.5 second;
When being uncovered: 1 second
When being covered: 0.5 second;
When being uncovered: 1 second
Housing Material Plastic, aluminum, stainless steel (precision casting), stainless steel (electropolished) Plastic, aluminum, stainless steel (precision casting), stainless steel (electropolished)
Protection Rating IP66/IP67 (NEMA Type 4X) IP66, IP67, IP68
Approvals FM (NI) Class I, Div 2, Groups A, B, C, D (DIP) Class II, III, Div 1, Groups E, F, G

FM (IS) Class I, II, III Div 1, Groups A, B, C, D, E, F

FM (XP) Class I, Div 2, Groups A, B, C, D (DIP) Class II, III, Div 1, Groups E, F, G

CSA (NI) Class I, II, III Div 2, Groups A, B, C, D, E, F, G

CSA (XP) Class I, II, III Div 1, Groups A, B, C, D, E, F, (GIS) Class I, II, III Div 1, Groups A, B, C, D, E, F, G
FM (NI) Class I, Div 2, Groups A, B, C, D (DIP) Class II, III, Div 1, Groups E, F, G

FM (IS) Class I, II, III Div 1, Groups A, B, C, D, E, F

FM (XP) Class I, Div 2, Groups A, B, C, D (DIP) Class II, III, Div 1, Groups E, F, G

CSA (NI) Class I, II, III Div 2, Groups A, B, C, D, E, F, G

CSA (IS) Class I, II, III Div 1, Groups A, B, C, D, E, F, G

CSA (XP) Class I, II, III Div 1, Groups A, B, C, D, E, F, G
CVR-600 CVR-625
Input Voltage Wide range 20...250V AC/DC Wide range 20...250V AC/DC
Power Consumption 3 VA 3 VA
Relay SPDT 5A 250 VAC SPDT 5A 250 VAC
Time Delay 1 second from stop of vibration;
2 to 5 seconds for start of vibration
1 second from stop of vibration;
2 to 5 seconds for start of vibration
Ambient Temperature Range (Electronics) -4°F to +140°F -4°F to +140°F
Process Temperature Range Standard: -4°F to +175°F;
High-Temperature: -4°F to +300°F
Standard: -4°F to +175°F;
High-Temperature: -4°F to +300°F
Minimum Material Density 3.5 lb./ft.³ 2 lb./ft.³
Maximum Pressure 145 psi 145 psi
Wiring Cable ½” ½”
Mounting 1” NPT 1-¼” NPT
Enclosure Diecast aluminum; NEMA-4 rated Diecast aluminum; NEMA-4 rated
Probe Material AISI 302 stainless-steel AISI 302 stainless-steel

VR Quick Connectors

Quick connector options allow vibrating probes to be removed and replaced without disconnecting wiring. Its benefits include:

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Faster, simplified sensor replacement

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Streamlined maintenance and repairs

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Reduced operational downtime


Vibrating Probe Documents