Dossier No.2: Ultra-sonic Tank Level sensor

High accuracy, reliability and easy installation were key demands when Electronic Partners was asked to develop a new, low cost universal tank level meter for use on small boats. We chose ultra-sonic technology because of the many benefits:

  • Ultra-sonic Tank Level sensornon-contact
  • fit any shape tank
  • does not require adjustment
  • works with any fluid
  • small, standard SAE 5 fitting
  • accurate and reliable
  • no wear and tear
  • not sensitive to fouling
  • cost effective solution

Building on years of commercial design experience with sonar technology Electronic Partners collaborated with the client’s R&D team to develop a ground breaking new approach to tank level monitoring.

Ultra-sonic Tank Level Sensor

  • The sensor measures the instantaneous fluid level several times per second and records all data in internal memory.
  • Sloshing and other fluid motion is constantly monitored and processed by the microcontroller.
  • The tank profile is factory-programmed into memory to ensure accurate readings.
  • All available data is utilised as the micro-controller derives the “real” fluid level.
  • Output data is available in several common formats, from the older resistive sensors as well as new, industry standard, 0-5V voltage or 4-20mA current loop outputs.
  • A single wire bi-directional serial protocol gives access to calibration data and a boot loader is included in the firmware


The Digital Signal Processing algorithm developed for this product has novel aspects that resulted in a patent. When introduced to the market in 2008 the product won the prestigious IBI Boat Accessory of the Year Award. It continues to receive great reviews.

Technology used:

  • Renesas M16c microcontroller: 16-bit flash based controller, with versatile DMA channels, high speed ADC, dual DAC output and DSP-friendly instructions
  • High-Gain analog front end with 4th order Band Pass Filter
  • Custom waterproof sonar transceiver puck and sonar output transformer
  • All firmware written in C
  • Hardware designed in Altium Designer