The LLF senses conductive nonhazardous fluids with low voltage contact probes. Internal logic circuitry controls the relay latching for tank Fill or Drain operations. Three diagnostic LEDs indicate the input and output relay states. The sensitivity is adjustable to control effects of liquid whiskers from the level probes. The Alarm version operates as a Dual High‑ and Low‑Level Alarm or it may be operated as either a High or Low Alarm. A delay timer reduces wave effects.