l Function virtually unaffected by flow, bubbles, turbulence, foam, vibration, solids content, coating products, liquid properties, and product variations
l No need for calibration and requires a minimum amount of installation
l Easy terminal access, polarity insensitive, and short circuit protection
l Electronic self-checking and condition monitoring
l Adjustable switching delay for turbulent or splashing applications
l Magnetic test point makes functional test easy
l “Fast Drip” fork design gives quicker response
l Explosion-proof/Flameproof and Intrinsically Safe options
The Rosemount 2120 is designed using the principle of a tuning fork. A piezo-electric crystal oscillates the forks at their natural frequency. Changes to this frequency are continuously monitored. The frequency of the vibrating fork sensor changes depending on the medium in which it is immersed. The denser the liquid, the lower the frequency.
When used as a low level alarm, the liquid in the tank or pipe drains down past the fork, causing a change of natural frequency that is detected by the electronics and switches the output state.
When the 2120 is used as a high level alarm, the liquid rises in the tank or pipe, making contact with the fork which then causes the output state to switch.
l Virtually unaffected by turbulence, foam, vibration, solids content, coating products, or liquid properties
l The 2120 is designed for operation in process temperatures from –40 to 302 °F (–40 to 150 °C)
l A ‘heartbeat’ LED indicates its operating state. The LED also flashes when the switch output is ‘off’ and is constantly lit when 'on'
l Adjustable switching delay prevents false switching in turbulent or splashing applications
l Fast Drip’ fork design gives quicker response time, especially with viscous liquids
l Rapid wet-to-dry and dry-to-wet time setting for highly responsive switching
l Fork shape is optimized for hand polishing to meet hygienic requirements
l No moving parts or crevices for virtually no maintenance
Specification Category | Details |
Product Model | Rosemount 2120 (Vibrating Fork Liquid Level Switch) |
Measurement Principle | Vibrating fork technology; piezoelectric crystal oscillates forks at natural frequency; output switches on frequency change due to liquid immersion |
Applications | High/low level alarm, pump control, overfill protection, dry-run protection; hygienic (3 A/EHEDG/FDA/ASME BPE), coating/aerated liquids, slurries |
Process Media Density | Minimum 37.5 lb/ft³ (600 kg/m³)Emerson |
Viscosity Range | 0.2 to 10,000 cP |
Operating Pressure | Full vacuum to 100 bar (1450 psi); connection dependent (threaded: up to 100 bar; Tri Clamp: 30 bar; flanged: per class rating) |
Process Temperature | -40 °C to 150 °C (-40 °F to 302 °F) |
Ambient Temperature | -40 °C to 80 °C (-40 °F to 176 °F) |
Switching Point | 0.5 in (13 mm) from fork tip/edge (varies with liquid density) |
Hysteresis | ±1 mm (±0.039 in) nominal (water) |
Switching Delay | User selectable: 0.3, 1, 3, 10, 30 seconds (dry to wet / wet to dry) |
Switching Mode | User selectable: Dry On or Wet On |
Power Supply | 12 Vdc (solar/battery option); 24 Vdc (standard); 110/230 Vac (relay version) |
Output Signals | Direct Load, PLC/PNP, Relay (DPCO), 8/16 mA, NAMUR |
Housing Material | Glass filled nylon (PA66 GF30), aluminum, 316 stainless steel |
Ingress Protection | IP66/IP67, NEMA 4X |
Process Connection Materials | 316/316L SST (standard); Alloy C 276; ECTFE coated SST |
Process Connections | 3/4 1 in NPT/BSPT/BSPP, Tri Clamp, flanged (ANSI/DIN/JIS) |
Fork Length | Standard: 1.7 in (44 mm); extended: up to 157.5 in (4000 mm) |
Weight | ~0.8–1.5 kg (1.8–3.3 lb) (housing dependent) |
Certifications | SIL 2 (IEC 61508), SIL 3 capable; ATEX, IECEx, FM, CSA, CE; 3 A, EHEDG, FDA, ASME BPE; WHG overfill protection; ABS, GL marine |
Diagnostics | Electronic self check, condition monitoring; heartbeat LED; magnetic test point |
Features | Fast drip fork (quick response for viscous liquids); no calibration; unaffected by turbulence/foam/bubbles |
Packaging: Original box
Esito (weifang) Automation Equipment Co., Ltd. specializes in industrial automation instrument development, production and sales, technical services, and supporting equipment supply of specialized companies. The main products are flow meters, level meters, temperature meters, pressure meters, electrical meters, thermal intelligent meters, programmable controllers (PLC), DCS distributed control systems, and eight series of more than 1,000 specifications. Its products and technologies are widely used in electric power, metallurgy, petrochemicals, environmental protection, plastics, food, printing, tobacco, textile, dyeing, and other fields.
We can offer rosemount, Endress+Hauser, yokogawa, Siemens, ABB,Fisher,Koso, Samson, Abzil, NELES,UE etc, Brands.
MaoGu Building Weicheng District, Weifang City, Shandong Province,China
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