The Endress+Hauser Liquiphant FTL50H is a compact, reliable vibrating fork point level switch designed for point level detection in liquids. It operates on the vibronic measuring principle, where a piezoelectric drive continuously excites the tuning fork at its mechanical resonance frequency of approximately 85 Hz. When the fork is submerged in liquid, the change in resonance frequency is detected, triggering a switching output. This technology ensures that the measurement is unaffected by flow, turbulence, bubbles, foam, vibration, solids content, or build-up, making it a superior alternative to float switches.

Key Benefits and Certifications

• Hygienic Design: The FTL50H features an electro-polished and passivated stainless steel fork and housing, making it easy to clean and ideal for hygienic applications. It holds key sanitary certifications including 3-A, EHEDG, and ASME BPE, and is made with FDA-conformed materials.
• Functional Safety: Certified for use in safety systems up to SIL2/SIL3 according to IEC 61508/IEC 61511-1, the device is suitable for critical overfill protection and other safety-related applications.
• Hazardous Area Approvals: The Liquiphant FTL50H is approved for use in hazardous areas with international certifications including ATEX, FM, CSA, IEC Ex, TIIS, INMETRO, and NEPSI, offering flexibility for global installations.
• Versatile Material Selection: Standard wetted parts are made of 316L stainless steel. For highly corrosive liquids, an optional Alloy C4 (2.4610) version is available for the fork and process connections.

Technical Specifications

Process Connections and Electronics

The FTL50H offers a wide range of process connections to suit various installation requirements, including threads (G3/4A, G1A), flanges (DN25-DN100, ASME 1\"-4\"), and hygienic connections such as Tri-Clamp, DIN 11851, DRD, SMS, and Varivent. The device supports multiple electronic inserts, including NAMUR, relay (DPDT), transistor, PFM signal output, and PROFIBUS PA communication, ensuring compatibility with most process control systems. The completely welded stainless steel housing provides IP67 protection for use in harsh environments.

Applications

The Liquiphant FTL50H is specifically designed for the food and beverage, pharmaceutical, and life sciences industries. Typical applications include overfill protection for tanks, pump protection (dry-run prevention), and point level detection in mixing vessels, storage tanks, and pipelines. Its robust design and extensive certifications also make it suitable for use in chemical plants and other industrial processes requiring high reliability and hygiene standards.

Key advantages include no calibration requirements, no mechanically moving parts, and built-in fork damage monitoring, which together ensure a long, maintenance-free operating life and low total cost of ownership.