

2511 Solids Level Switch (Vibrating Fork)
SKU: 2511
Cost-effective vibrating-fork point-level switch for fine-grained and powdered solids — flour, cement, sand, plastic pellets, grain. Fork resonates at a known frequency in air; when product touches the fork the frequency drops and the switch trips. No moving parts, no calibration, immune to dust and electrostatic charge. Operates up to 150°C. Best for storage and process vessels where the 2501 paddle is over-spec and the 2521 sensitivity isn't required.
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Cost-effective vibrating-fork point-level switch for fine-grained and powdered solids — flour, cement, sand, plastic pellets, grain. Fork resonates at a known frequency in air; when product touches the fork the frequency drops and the switch trips. No moving parts, no calibration, immune to dust and electrostatic charge. Operates up to 150°C. Best for storage and process vessels where the 2501 paddle is over-spec and the 2521 sensitivity isn't required.
The Rosemount 2511 Solids Level Switch (Vibrating Fork) # 2511 is manufactured by Rosemount. Valley Instrument Service is an authorized Rosemount dealer offering full sales support, NIST-traceable calibration, and expert technical assistance.
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Contact Us or Call (661) 327-8681Configure Your Rosemount 2511 Solids Level Switch (Vibrating Fork)
Tuning-fork solids level switch with piezo-electric crystal oscillator. Fork resonance changes when covered by bulk solids medium. Ideal for fine-grained and powdered materials. Hygienic stainless steel forks. Short-fork design fits in small pipes and limited spaces. Vertical, horizontal, or angled mounting.
Required Specifications
8 of 8 selected- Thermal Profile:
- MW/O extension tube (up to Tprocess = 150°C (302°F) at Tamb < 40°C (104°F))
- Process Connection/Thermal Extension Tube:
- S316/316L/316TI Stainless steel (1.4581/1.4404/1.4571)
- Conduit Entry / Cable Threads:
- 4NPT 1/2-in. tapered ANSI B1.20.1 (1off conduit + 1off Ex-d blind plug)+$34.58
- Process Connection Rating:
- DZEN 1092-1 PN6 flange
- Process Connection Type:
- FFlat Face Flange
- Electronic Type:
- VRelay DPDT 19 .. 230 V AC 19 .. 40 V DC+$77.47
- Fork Length:
- A0000Standard Length 6.68in (170mm)
- Product Certifications:
- NANo Hazardous Locations Certifications
Rosemount is configurator-heavy and quote-only. Valley Instrument verifies option compatibility, lead time, and pricing before confirming your order.
Related Products

2501 Solids Level Switch (Rotating Paddle)
Heavy-duty rotating-paddle point-level switch for bulk solids — a small motor turns a paddle inside the silo; when product covers the paddle the motor stalls and the switch trips. Works on virtually all bulk solids regardless of dielectric, electrostatic charge, or dust. Withstands extreme temperatures up to 1100°C and demanding mechanical conditions (heavy product loads, abrasive media). Best for cement, aggregates, ash, grain, and any bulk solid where vibrating or capacitance sensors fail. Vertical, horizontal, or oblique mounting.

2521 Solids Level Switch (High-Sensitivity Vibrating Fork)
High-sensitivity variant of the 2511 vibrating fork — same proven fork-resonance technology, tuned for extremely low-density bulk media (below 0.3 lb/ft³ / 5 g/L). Catches the fork frequency change even when very light powders or fluffy materials touch it. Best for low-density polymers, fluffy fines, light insulation media, and other powders where the standard 2511 might miss the trigger. Operates up to 150°C. Same process connections, fork extensions, electronics options, and approvals as the 2511.

2535 Solids Level Switch (Vibrating Rod)
Vibrating-rod (single-tine) point-level switch for fine grains and powders — alternative to the tuning-fork 2511/2521 for media that bridge between fork tines. The single-rod geometry is harder to bridge, more reliable in clumpy or sticky powders. Operates up to 150°C. SST construction, suitable for hazardous and dusty environments. Best for fine powders prone to bridging, light solids, and any storage vessel where fork-style switches have given trouble.

2555 Solids Level Switch (Capacitance Probe)
RF-capacitance point-level switch for low-dielectric solids and extreme-condition installations — measures the capacitance change between probe and silo wall when product covers the probe. Active Shield Technology prevents false trips from material build-up on the probe (the most common failure mode of older capacitance switches). Withstands up to 500°C, high mechanical stress, and high tensile forces. Best for low-dielectric materials (some plastics, oils on solids, low-conductivity powders) and high-temperature applications where vibrating-fork/rod 2511/2521/2535 fall outside their thermal envelope.
