Discover the key distinctions between various technologies used for solids level switches
Products
Optimize filling and emptying cycles with reliable solids level switches
Rosemount solids level switches are a reliable and cost-effective point level solution to detect the presence or absence of bulk solids in a variety of applications, such as in the food and beverage industry, chemical processing, and wastewater treatment. Emerson’s portfolio includes capacitance, rotary paddle and vibration technologies, providing easy-to-install and accurate level detection and control indifferent media types and process conditions.
Key Benefits Of Using Solid Level Switches
Reliable point level detection prevents the risk of overspills and increases plant safety
Hazardous location approvals are available for all Rosemount Solids Level Switches
Configurable fail-safe high or fail-safe low settings ensure safe operation during power failure
The Rosemount 2555 Capacitance Probe enables automatic or manual function checks for enhanced reliability
The Rosemount 2500 series handles all bulk solids regardless of particle size.
Sensitivity settings enable reliable point level detection from low-density to coarse and sticky media.
Switches withstand extreme temperatures and pressures.
Suitable for full, empty, or demand detection, both indoors and outdoors.
EHEDG Hygienic Approval available for the Rosemount 2555.
Sliding sleeve options offer flexible point level detection.
The Rosemount Solids Level Switches are maintenance-free and unaffected by dust, offering:
Reliable operations, even in media where caking or buildup is common, or when there are temperature and pressure changes
Resistance to corrosive materials, high tensile forces, and mechanical loads.
Availability of remote housing options for high-vibration processes
Adjustable switching delay settings
Rapid response to fast emptying and filling processes
Flexible mounting locations: switches can be installed vertically, horizontally, or obliquely.
Easy commissioning: plug and play for all switches.
Rotatable housings for installation flexibility.
Compact design suitable for various mounting locations.
Solids Level Switches Comparison
Vibrating Rod Level Switch
Suitable for light, free-flowing bulk solids such as dry powders or granules, regardless of particle size.
Effective for media densities starting from 1.2 lb/ft3 (20 g/l).
Features small process connections down to 1” NPT and a compact size.
All wetted parts are made of food-grade stainless steel, making it ideal for hygienic applications.
Smooth single rod design eliminates the risk of bridging or jamming.
Vibrating Fork Level Switches
Versatile vibrating level switches for fine-grained and powdered bulk solids with particle sizes up to 0.39in. (10mm)
Enhanced version (Rosemount 2521) for extremely low media density, below 0.3 lb/ft3 (5 g/l).
Standard version (Rosemount 2511) for media density above 3.8 lb/ft3 (30 g/l).
Wide range of output options, including NAMUR.
Extra mechanical robustness in the 2521 model makes it suitable for high-vibration applications.
Remote housing options available.
Rotating Paddle Level Switches
Flexible technology suitable for all bulk solids applications, regardless of particle size.
Designed for media density above 0.9 lb/ft3 (15 g/l).
Robust rotating paddle level switch tolerates high mechanical load and extreme temperatures up to 2012°F (1100°C).
Unaffected by dust, electrostatic charging, and sticky media or buildup.
Sensitivity settings allow handling of different media types and densities.
Patented mechanical hysteresis extends product lifetime and minimizes disturbances during emptying and filling cycles.
Capacitive Level Switch
Highly capable level switch that detects all types of bulk solids with a dielectric constant as low as 1.5, unaffected by particle size.
Configurable sensitivity settings via a user-friendly local operator interface.
Operates at high temperatures up to 932°F (500°C) and high pressures up to 363 psi (25 bar).
Unique Active Shield Technology prevents media buildup.
Self-diagnostics through automatic or manual function tests.
Fully PFA-coated version available for aggressive and adhesive media.
Automatic calibration for simple and quick commissioning.
EHEDG approval for hygienic applications.
Remote housing options available.
Resources
Rosemount Solids Level Measurement Portfolio
Rosemount 2521 Solids Switch Vibrating Fork - How it works
Rosemount 2511 Solids Switch Vibrating Fork - How it works
Frequently Asked Questions
Find answers to the most frequently asked questions about solids level switches
Solids level switches are used for full, demand or empty detection of all kinds of bulk solids. It can be used for overspill prevention in all kinds of storage and process vessels or silos.
A vibronic level switch is driven by a piezo electric crystal which oscillates in its natural frequency when the switch is powered and uncovered by media. When the vibrating fork tines or rod is covered by media the sensor will detect the change in frequency and switch its output signal to covered state. When the media is not covering the fork tines or rod anymore the frequency will change again and thus also the output signal will switch to uncovered state.
The rotating paddle switch is driven by a synchronous motor which rotates a paddle vane at 1 or 5 revolutions per minute. The rotation stops when the vane is hindered by media and hence the output will switch from uncovered to covered state. When the media is removed from the vane, the rotation will resume, and the output signal switches to uncovered.
Capacitance level switches use the principle ofmeasuring capacitance through radio frequency(RF) to detect the presence or absence of solidsmedia. When the materials in the vessel risesand covers the rod, it causes an increase ofcapacitance which is detected by the sensor andthe output signal will switch to covered state.When the media in the vessel falls away from theprobe level, it causes a decrease in capacitanceand the output switches to uncovered state.