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:

non-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.

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

Accolades

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