Sensor Status Notification
A red LED indicator on the sensor housing displays whether the probe is covered, uncovered, or experiencing a fault condition to help prevent process interruptions.
Capacitance Probes for Reliable Point Level Detection
BinMaster PROCAP® capacitance probes provide reliable point level detection for solids, powders, granules, pellets, and liquids in bins, tanks, silos, and process vessels.
These sensors detect presence or absence of material by measuring changes in capacitance caused by differences in dielectric constant between air and the stored material.
Designed for durability and accuracy, BinMaster PROCAP probes are manufactured in Lincoln, Nebraska, USA and engineered for dependable operation in demanding industrial environments.
A Capacitance Probe for Every Purpose
PROCAP capacitance probes are widely used in agriculture, plastic, cement, chemicals, food processing, pharmaceuticals, mining, and industrial manufacturing.
Capacitance sensors from BinMaster offer:
- High-sensitivity detection
- Multiple probe styles for different materials
- Custom lengths and configurations
- A long service life with minimal maintenance
Choose from seven standard configurations—or three mini probes—to best meet your bulk material and industry needs.
Or, contact us to design your custom capacitance sensor!
PROCAP Capacitance Probe Models
Standard Probes
The PROCAP I and PROCAP II standard capacitance probes provide reliable point level detection for solids and liquids.
Available probe materials include Delrin®, Teflon®, stainless-steel, and bare metal probes.
Each probe is custom assembled to customer specifications based on the material type, mounting location, and vessel design.
Sanitary Capacitance Probes
PROCAP sanitary probes are designed for food, beverage, and pharmaceutical processing.
Sensors include a thread-free mounting flange, tri-clamp sanitary connection, clean-in-place compatibility, and compliance with 3-A, USDA, and food-grade standards.
Ideal for sanitary tanks, ingredient processing systems, and hygienic manufacturing environments.
Bendable Capacitance Probes
A bendable probe allows the sensing element to be shaped to avoid obstacles inside a vessel.
Typical applications include mixers, small hoppers, and process tanks with internal structure.
This flexible design allows installation where rigid probes cannot fit.
Heavy-Duty Capacitance Probes
Heavy-duty PROCAP HD probes feature a 1-inch solid stainless-steel sensing rod.
These probes are designed for high temperatures up to 500°F, abrasive or heavy materials, and harsh industrial environments.
They are commonly used in power plants, cement facilities, and coal handling operations.
Flush-Mounted Probes
PROCAP FL flush-mounted probes are non-intrusive sensors installed directly into the vessel wall.
These probes are ideal when level detection is required in chutes or conveyors, but material flow could damage a standard probe or installation space is limited.
Flush mounting allows the sensor to detect material without extending into the vessel.
Remote Electronics Probes
PROCAP Remote Electronics probes allow the sensing probe to be separated from the electronics housing.
Electronics can be mounted up to 75 feet away from the probe, making them suitable for high vibration environments, high process temperatures, and difficult installation locations.
Compact & Mini Capacitance Probes
Compact capacitance sensors provide reliable level detection in small vessels and tight installation spaces.
Compact PROCAP probes are ideal for chutes, conveyors, pipes, small hoppers, and limited mounting space.
These probes provide the same reliable detection as full-size sensors in a smaller footprint.
Additionally, mini capacitance probes—or MCP sensors—are available in three models based on bulk materials being measured.
Mini Capacitance Probe Options
MCP-100 for Liquids
The MCP-100 is a miniature capacitance probe designed for liquid level measurement and pressure detection.
Applications include food processing, pharmaceutical manufacturing, and hygienic processing systems.
The compact design and stainless-steel enclosure are ideal for sanitary tanks and clean-in-place systems.
MCP-200 for Bulk Solids
The MCP-200 provides point-level detection for bulk solids, including granules, pellets, and powders.
Typical uses include hoppers, feeders, and compact storage vessels.
MCP-200 offers a stainless-steel housing with hygienic options for food and pharmaceutical processing.
MCP-300 Extended Probe
The MCP-300 features an extended stainless-steel probe customizable from 2.5 inches to 9.8 inches.
Applications include breweries, sairy processing, food ingredient tanks, and pump rooms for reliable leak detection.
How Capacitance Probe Level Sensors Work
PROCAP capacitance probes detect material level by measuring changes in electrical capacitance.
- The probe and vessel wall form a capacitor. The probe acts as one conductive plate of a capacitor, and the metal tank wall acts as the other.
- As material contacts the probe, the dielectric constant changes.
- The sensor electronics measure this change in capacitance.
- When the threshold is reached, the sensor triggers a relay output.
PROCAP probes are extremely sensitive and can detect capacitance changes as small as one picofarad.
To provide clear status indication, sensors are commonly wired to alarm panels, lights, horns, or PLC inputs.
PROCAP Mounting Options
Capacitance probes can be installed in several vessel locations, depending on the application.
Mounting Locations
Top mounting for high-level detection, side mounting for high or mid-level detection, or cone mounting for low-level alerts.
Mounting Plates
Mounting plates are available in powder-coated carbon steel for sloped roofs. Available angles include 0°, 10°, 20°, and 30°. Sanitary installations may use stainless-steel mounting plates.
Additional Hardware
Choose from raised-face blind flanges; carbon or stainless-steel flanges; 1”, 2”, 3”, or 4” flange sizes, and ¾” NPT threaded connections.
Any questions while selecting your mounting accessories? Contact us—we're happy to assist.
PROCAP Sensor Features
PRO-Shield Technology
Protects the sensor from false readings caused by material buildup or bridging between the probe and vessel wall, allowing the probe to operate reliably in dusty, sticky, or clingy materials.
Simple Quick-Set Calibration
Calibration is fast and easy using two single-turn potentiometers. This allows sensitivity adjustments even when no material is present in the vessel.
Adjustable Time Delays
Set time delays up to 30 seconds before the sensor signals a level change. Prevent false alarms caused by sudden material movement, splashing liquids, and process disturbances.
RF Interference Protection
PROCAP probes are immune to radio frequency interference from plant equipment or radios, helping to ensure consistent sensor operation.
Versatile Customization
Each PROCAP probe is built to order based on material type, vessel geometry, process conditions, and mounting requirements.
Probe Types for Custom Capacitance Sensors
PROCAP probes are available in multiple probe styles. Compare different probes below to determine the best fit for your application.
- Delrin® shielded
- Delrin® extended shielded
- Delrin® unshielded
- 3-A sanitary Delrin® probes
- Teflon® shielded
- Teflon® extended shielded
- Teflon® unshielded
- Bare metal shielded
- Bare metal unshielded
- Heavy-duty stainless-steel probes
- Hanging stainless-steel cable probes
- Bendable probes
- Flush-mounted probes
| Type | Standard Shielded Delrin/Teflon-Sleeved Probe | Extended Shield Delrin/Teflon-Sleeved Probe | Stubby Shielded Delrin/Teflon-Sleeved Probe | Shielded Delrin-Sleeved Sanitary/3-A Probe | Flush-Mounted Shielded Probe | Bare Shielded OEM Probe | Shielded Teflon-Sleeved 316 SS Hanging Flexible Cable Extension | Shielded Bare 316 SS Hanging Flexible Extension | Unshielded Bare 316 SS Hanging Flexible Cable Extension | Unshielded Delrin/Teflon-Sleeved Probe | Stubby Unshielded Delrin/Teflon-Sleeved Probe | Unshielded Bare Stainless-Steel Probe | Shielded Bare Stainless-Steel/Ceramic High-Temperature Probe | FI Fitting | Stainless-Steel or Galvanized Lag |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Description | Most versatile all-purpose probe. It works reliably in bulk solids, powders, slurries, and liquids. PRO-Shield protection. | 10” extended PRO-Shield; used when mounting the probe through a nozzle or standpipe. | For low-level applications where minimal projection is preferred due to space constraints or excessive weight that could damage a longer probe. | Meets 3-A and USDA sanitary standards for clean-in-place construction. Designed for quick disconnect for ease of inspection and cleaning. | Mounts flush; space-constrained areas where material flow or bridging may damage standard probes. Special bin wall adapter eliminates false signals due to buildup. | Bare shielded probe; can modify length in the field. Features PRO-Shield protection against false readings. | Top-mounted level detection. Used in lump materials that might damage a rigid probe or that are not compatible with SS. Cable can be cut to length in the field. | Top-mounted level detection. Used in lump materials that might damage a rigid probe. PRO-Shield protection. Cable can be cut to length in the field. | Top-mounted level detection. Used in lump materials that might damage a rigid probe. Cable can be cut to length in the field. | Lower-cost, versatile probe. | Minimal insertion into pipes and small hoppers for low-level detection with space constraints or in or heavy materials that could damage longer probes. | Use in powder and dry bulk solid materials. Length can be modified in the field. | Heavy-duty probe for temps past 500°F (260°C). Remote electronics can be located up to 20 feet from the probe. | Extended lag fitting to get past excessive buildup or through a thick wall. | Extended probe through thick vessel walls or double-walled bins. Can also be used to lag the electronics away from heat. |
| Max Temp | Delrin-sleeved: 250ºF (121ºC); Teflon-sleeved: 500ºF (260ºC) | Delrin-sleeved: 250ºF (121ºC); Teflon-sleeved: 500ºF (260ºC) | Delrin-sleeved: 250ºF (121ºC), Teflon-sleeved: 500ºF (260ºC) | 250ºF (121ºC) | Standard probe: 150ºF (65°C); High-temp probe: 450ºF (232°C) | 250ºF (121ºC) | 500ºF (260ºC) | 250ºF (121ºC) | Standard probe: 250ºF (121ºC); High-temp probe: 500ºF (260ºC) | Delrin-sleeved: 250ºF (121ºC); Teflon-sleeved: 500ºF (260ºC) | Delrin-sleeved: 250ºF (121ºC); Teflon-sleeved: 500ºF (260ºC) | Standard probe: 250ºF (121ºC); High-temp probe: 500ºF (260ºC) | 1000ºF (538ºC) | 250ºF (121ºC) | Delrin-sleeved: 250ºF (121ºC); Teflon-sleeved: 500ºF (260ºC) |
| Probe Material | 5/8” diameter 316 SS, Delrin/Teflon sleeved | 5/8” diameter 316 SS, Delrin/Teflon sleeved | 5/8” diameter 316 SS, Delrin/Teflon sleeved | 5/8” diameter 316 SS, Delrin sleeved | Polyethylene, High Temp, Teflon | 5/8” diameter 316 SS/Bare with Delrin insulator | 316 SS, 1/4” diameter cable with Teflon sleeve and insulator | 316 SS, 1/4” diameter cable with Delrin insulator | Standard probe: 316 SS, 1/4” diameter cable with Delrin insulator; High-temp probe: 316 SS, 1/4” diameter cable with Teflon insulator | 5/8” diameter 316 SS, Delrin or Teflon sleeved | 5/8” diameter 316 SS, Delrin or Teflon sleeved | Standard probe: 5/8” diameter 316 SS/bare with Delrin insulator; High-temp probe: 5/8” diameter 316 SS/bare with Teflon insulator | 1-1/8” diameter 316 SS with ceramic inserts | Fitting material: 316 SS | N/A |
| Lengths | 10.63”, 18”, 24”, 30”, 36”, 48”, and custom | 15”, 18”, 24”, 30”, 36”, 48”, and custom | 6.5” | 4”, 6.5”, 10.63”, 18”, 24”, 30”, 36”, 48”, and custom | N/A | 7 inches to 8 feet | 16 inches to 25 feet | 16 inches to 35 feet | 16 inches to 35 feet | 10.63”, 18”, 24”, 30”, 36”, 48”, and custom | 4” | 3”, 4”, 6”, 10.19”, 18”, 24”, 30”, 36”, 48”, 72”, 96”, and custom | 9” | N/A | 6” to 24” |
| Fitting Options | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150# Raised face flanges | 3/4” NPT, 1-1/4”, NPT, 1” food grade, 1”/2”/3”/4” 150# Raised face flanges | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150#, Raised face flanges | 1” or 2” sanitary, 316 SS fitting for use with tri-clamp | 5.75” hole mounted on 7.00” bolt circle, or when using bin wall adapter, 8.50” hole mounted on 9.50” bolt circle | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150#, Raised face flanges | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150#, Raised face flanges | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150#, Raised face flanges | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150#, Raised face flanges | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150#, Raised face flanges | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150#, Raised face flanges | 3/4” NPT, 1-1/4” NPT, 1” food grade, 1”/2”/3”/4” 150#, Raised face flanges | 1-1/4” NPT | 3/4” NPT to lag out, 1-1/4” NPT to lag in | 3/4” NPT to lag out, 1-1/4” NPT to lag in |
| Power Pac Option | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I 3-A & II 3-A | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | PROCAP I & II, PRO Remote, PRO Auto-Cal | Remote electronics only | PROCAP I & II, PRO Remote, PRO Auto-Cal with all Delrin sleeved, bare, and flexible probes | PROCAP I & II, PRO Remote, PRO Auto-Cal with all Delrin sleeved, bare, and flexible probes |
| Applications | Solid, liquid and slurry materials in bins, tanks, chutes, and spouts. | Solid, liquid and slurry materials; in a nozzle or standpipe or when excessive sidewall buildup may occur. | Low-level detection where material load on probe may cause damage, or when working in a restricted area or small vessel. | Solid, liquid and slurry materials in dairy, pharmaceutical, and food-grade applications where 3-A/USDA sanitary standards apply. | Detects presence/level of material that may bend or break probes. Works well in heavy and/or chunky materials. | Powders and dry bulk solid materials that may build up and coat the probe. Used in bins, tanks, chutes, and spouts. | Use where conductive material may leave residue on the probe. Note: Any buildup from the wall to the active portion of any unsleeved bare probe will short out the two conductors. | Top-mounted solid, liquid and slurry applications. | Top-mounted solid, liquid and slurry applications. | Works best if top-mounted or side-mounted in vessels with free-flowing material without sidewall buildup. | Designed for minimal insertion into pipes, small hoppers, vessels, or other restricted areas. | Powders and dry bulk solids. Works best when top mounted or side mounted in vessels with free-flowing dry material without sidewall buildup. | Solid, liquid and slurry materials in bins, tanks, chutes, and spouts. | Solid, liquid and slurry materials in bins, tanks, chutes, and spouts. | Solid, liquid and slurry materials in bins, tanks, chutes, and spouts. |
When and Where to Use Capacitance Sensors
Different point level technologies perform best depending on the material characteristics and process conditions.
Typical materials measured by capacitance probes include chemicals, liquids, powders, plastic pellets, and food ingredients.
Use capacitance probes when:
- Measuring materials with a consistent dielectric constant
- Liquids or solids require sensitive level detection
- Installation space is limited
- A non-mechanical sensor is preferred
- Detection is required in liquids or clingy materials
Capacitance, Rotary, Or Vibrating Rod?
Choosing the Right Level Sensor
Selecting the best sensor depends on several factors: including material type, vessel design, and process conditions.
Other technologies may be better suited for specialized materials or environments. BinMaster engineers can help determine the best level sensing technology for your application.
Rotary Level Sensors
Used in free-flowing bulk solids with a moderate to high bulk density when simple mechanical detection is sufficient.
Vibrating Rod Sensors
Thrives in lightweight flakes or fluffy powders with a bulk density as low as 1.25 lb./ft.³, which can be difficult to detect with capacitance.
Challenging Bulk Materials
Capacitive sensing is best for most liquids and solids, but bulk materials with a very low dielectric constant are not suited for a capacitance probe.
Dielectric Constant Guide
Best Materials for Capacitance Sensors
Capacitance probes are commonly used with materials with moderate to high dielectric constants or liquids that exhibit a clear signal change upon contact with the probe. This includes:
- Grains such as corn, wheat, barley, and rice
- Plastic pellets, powders, and resins
- Chemicals and industrial powders
- Cement, lime, and fly ash
- Sugar, flour, salt, and other food ingredients
- Oils, water, and water-based liquids
- Slurries, adhesives, and coatings
These materials allow the probe to easily detect the transition between air and material contact, providing reliable point level detection.
