Overview - Hach AV9000 Manual Del Usuario

Confined spaces are not designed for human occupancy. Confined spaces have a restricted entry
and contain known or potential hazards. Examples of confined spaces include manholes, stacks,
pipes, vats, switch vaults and other similar locations.
Standard safety procedures must always be obeyed before entry into confined spaces and/or
locations where hazardous gases, vapors, mists, dusts or fibers can be present. Before entry into a
confined space, find and read all procedures that are related to confined space entry.

Overview

Figure 1 shows an overview of the Submerged Area Velocity (Sub A/V) Sensor and components.
The sensor is used with a flow logger to measure the flow rate in open channels.
The Sub A/V Sensor connects directly to the Sigma family of flow loggers. An AV9000 Area Velocity
Analyzer Module is required to connect the Sub A/V Sensor to a FL900 Series flow logger.
The sensor is available in oil-filled and non-oil-filled versions. The non-oil sensor is used for
reasonably clear sites, or sites where the pipe may become dry. The oil-filled sensor is used for sites
with high levels of biological growth, grit or silt.
Note: Do not use an oil-filled sensor in a pipe that may become dry.
Theory of operation
A pressure transducer in the sensor converts the pressure of the water to a level measurement. The
level measurement and the user-entered channel geometry are used to calculate the wetted area of
the flow stream.
The sensor also contains two ultrasonic transducers. The flow logger converts the doppler shift in the
returned ultrasound signals to a velocity measurement. The flow rate equals the wetted area
multiplied by the velocity.
Figure 1 Overview of the Submerged Area Velocity Sensor
1 Sensor cable
2 Sensor (available in oil-filled and non-oil filled
versions)
3 Desiccant hub
4 Air tube
6 English
5 Sensor connector
6 Carabineer
7 Lanyard