The AM-UST from Aquametrix - USA is one of the most compact and cost-effective level transducer on the market. Inside a package about the size of a 1/4-DIN enclosure is a full feature ultrasonic transducer that outputs directly either a 4-20 mA analog signal or two Modbus over RS485 digital signals. The unit is powered by a 9 -36 VDC power supply.
The matching impedance between the crystal transducer and the air results in a very narrow beam angle. The embedded SENSOR LOGIC software automatically locks onto the true level while filtering out false echoes.
Simply plug the SENSOR adapter into your computer and you can program the AM-UST. To calibrate simply set the empty level and span. This automatically sets the 4-20 mA output.
With no moving parts the AM-UST will provide years of maintenance-free operation.