Sequoia LISST-SL, Руководство по эксплуатации

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LISST-SL V2.1
User’s Guide
1
I. Introduction
Dear LISST-SL Customer:
Thank you for purchasing the LISST-SL iso-kinetic sediment grain-size analyzer. It is a
sophisticated system for use from bridges. It provides all the data necessary to compute
sediment transport in a river. The measured parameters are: river velocity, sediment
concentration and size distribution as a function of depth, depth of the instrument at any
time, and water temperature. The combination of sediment, velocity, and depth data permit
estimation of sediment transport rate, also called sediment flux.
In the shipment to you, you will find 3 main items which comprise the LISST-ST Instrument
System. These are: the LISST-SL submersible sensor, a Topside Controller Box (TCB),
and a B-reel if you ordered one. If you did not order a B-reel, you will need to procure one
from one of many vendors in the US. There are many more items of accessories, and
software for downloading and processing raw data. A full list of items shipped to you
appears in Chapter 2, Contents and Technical Specifications. We now introduce you to
each of these.
1.1 LISST-SL Sensor
The main system is the streamlined submersible LISST-SL sensor. This is only a sensor; it
needs power to operate, and it has no data storage capacity. So, it must be connected to
the Topside Controller Box (See Section 1.3).
The LISST-SL sensor contains the laser optics, scattered light sensing photodiodes and
amplifiers, and an iso-kinetic pump. Whenever power is applied to the -SL (from the TCB,
via a short SL-to-TCB cable, or via the B-reel cable), a dedicated microprocessor inside the
–SL begins operation. It senses stream velocity from the pitot tube (5), turns on and
controls operation of the internal pump to match stream velocity (i.e. in iso-kinetic mode),