ABB ST400 flow transmitter

The LST400 is an ultrasonic level transmitter capable of measuring liquid level or solid applications up to 15 m (50 ft.) or flow rates in all types of open channel flow applications. The transmitter has a single 4 to 20 mA DC analog output with HART 7 and five (5) relay outputs. A transducer is fitted to the top of a silo or tank, facing down towards the material being measured.