The Endress+Hauser Liquiphant FTL80 is a vibrating fork point level switch designed specifically for FailSafe overfill prevention in hazardous area applications. With functional safety certified to SIL3 (IEC 61508 Ed.2.0 / IEC 61511-1), a single FTL80 device can provide the highest level of safety integrity for critical overfill protection. The permanent LIVE signal continuously monitors functional health, and the proof test interval extends up to 12 years—reducing maintenance burden without compromising safety.

The FTL80 operates on the vibronic (tuning fork) principle, making it immune to changing media properties, flow, turbulence, gas bubbles, foam, vibrations, and build-up. It detects liquids with a minimum density of 0.4 g/cm³ and handles viscosities up to 10,000 mPa·s for MAX detection. The 4-20 mA output per NAMUR NE43 integrates directly with safety PLCs or the companion Nivotester FTL825 switching unit for dual safety contacts.

Wetted parts are available in 316L stainless steel or Alloy C (Hastelloy) for corrosive media. Process connections include flanges (DN25-DN100, ASME 1"-4"), threaded options (G¾, G1, R¾, R1, MNPT¾, MNPT1), and the sensor is rated for process temperatures from -60 to 280°C and pressures from vacuum to 100 bar. International hazardous area certifications include ATEX, IECEx, FM, CSA, NEPSI, and EAC, with additional WHG overfill approval and marine certifications (GL, ABS, LR, BV, DNV).

Features

• FailSafe design — permanent LIVE signal monitors functional safety
• SIL3 per IEC 61508 / IEC 61511-1 with up to 12-year proof test interval
• Immune to flow, turbulence, foam, gas bubbles, vibration, and build-up
• Min. density 0.4 g/cm³; viscosity ≤10,000 mPa·s (MAX) / ≤350 mPa·s (MIN)
• 4-20 mA output per NAMUR NE43 — direct PLC or Nivotester FTL825 connection
• Wetted materials: 316L or Alloy C
• Process: -60 to 280°C, vacuum to 100 bar
• ATEX, IECEx, FM, CSA, NEPSI, EAC; WHG overfill; marine (GL/ABS/LR/BV/DNV)