LLHP

SST’s LLHP series of liquid level switches are designed with larger mounting threads and rugged stainless steel housings, making them ideal for demanding or chemically aggressive environments.

Each sensor is microcontroller-based and solid-state, using an infrared LED and phototransistor optically linked through the sensor tip when in air. When liquid covers the tip, the infrared light refracts out, causing the sensor output to change. The design is compatible with almost all liquid types—whether oil- or water-based—and is unaffected by ambient light, surface foam, or small air bubbles.

The LLHP range supports both N and P-type output configurations. These can sink or source up to 100mA at 4.5 to 15.4 VDC, or up to 800mA at 10 to 45 VDC. Outputs are user-configurable to be active in either dry or wet states, providing flexible integration into a wide range of systems.

Constructed with a robust stainless steel body and a chemically resistant Polysulfone or Trogamid sensing tip, the LLHP sensors are available with a variety of terminations. They are suitable for standard operating temperatures of -25 to +80°C or extended ranges from -40 to +125°C, making them a versatile choice for challenging applications.