…Wherein we’ll learn about the LISST-ABS and the LISST-200X

(Part XI can be found here: https://www.sequoiasci.com/article/the-history-of-sequoia-part-xi/)

In 2013 Yogi came up with an idea for a point sensor for measuring suspended sediment concentration; the LISST-ABS. It was developed in collaboration with Dr. Ramon Cabrera, the co-founder of Sontek. The LISST-ABS was Sequoia’s first acoustic sensor, and it was designed specifically for measuring suspended sediment concentration at a point in rivers. Consequently, it had no pressure sensor, memory, or internal power of any kind – the core user of the LISST-ABS is a user that wants to integrate it into existing infrastructure such as dataloggers or instruments that can power and log external sensors. It has become popular within the hydropower industry for turbine monitoring.

LISST-ABS

In 2012, Sequoia decided it was time to re-engineer the LISST-100X, which had been in production since the early 2000’s. The LISST-200X took four years of near-constant development and was released in 2016. It was an instant hit. In 2019 its capability was expanded so that it could power and accept three external analog sensors. In 2021 it was updated to output fully processed data in real time on the endcap. In 2022 it was further expanded so that the user could reconfigure the endcap connectors in software, effortlessly switching between the various endcap configurations, something that previously required the instrument to come back to Sequoia.

In Part XIII we’ll learn about the LISST-AOBS and some of the ongoing developments at Sequoia.