Hach Sigma 950, Инструкция по эксплуатации инструмента

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Sensor Installation
6.2 In-Pipe Zero Deadband Ultrasonic Depth Sensor
The in-pipe zero deadband ultrasonic depth sensor is used in pipes where level
measurement near the top of the pipe is desired. The sensor will read the level until liquid
reaches from the bottom of the sensor housing.
6.2.1 In-Pipe Zero Deadband Ultrasonic Depth Sensor Connection
6.2.2 Programming the In-Pipe Zero Deadband Ultrasonic Depth Sensor
The in-pipe zero deadband ultrasonic depth sensor does not require operator
programming, unless more than one sensor option is connected to the 950
Flow Meter.
When more than one sensor option is connected:
1. From the Main Menu, select
OPTIONS > LEVEL SENSOR
2. Select Ultra-Sonic Sensor using the
CHANGE CHOICE
soft key, then
press
ACCEPT
.
6.2.3 Beam Angle
The narrow beam of sound that emanates from the bottom of the in-pipe ultrasonic
sensor spreads out at an angle of ±12° (-10 dB) as it travels away from the sensor. This
means that if the sensor is mounted too high above a narrow channel, the beam may be
too wide when it reaches the bottom of the channel. This may cause false echoes from
the sides of the channel walls.
6.2.4 Calibrating the In-Pipe Zero Deadband Ultrasonic Depth Sensor
Calibrate the in-pipe sensor each time the sensor is installed at a new site. Calibrate the
in-pipe via one of two methods; Liquid Depth or Sensor Height. Each method has its own
advantages and disadvantages. Liquid Depth calibration is the recommended calibration
method. Use the sensor height method
only when Liquid Depth calibration is not an
option. An Invisible Range can also be set which allows the transducer to ignore
reflections from obstructions between the sensor and the water surface, such as ladder
rungs, channel side walls, etc.
1. From the Main Menu, select
OPTIONS > ADVANCED OPTIONS.
2. Highlight Calibration, using the
UP
and
DOWN
soft keys. Press
SELECT
.
3. Highlight Ultra-Sonic Sensor, using the
UP
and
DOWN
soft keys. Press
SELECT
to
continue.
4. Highlight Calibrate U-Sonic Sensor and press
SELECT
.
5. Select the type of ultrasonic transducer (In-Pipe), using the
CHANGE CHOICE
soft
key.
6. Press
ACCEPT
to continue.
Table 12 In-Pipe Zero Deadband Ultrasonic Depth Sensor Connector
Pin Assignments
Pin Signal Description Wire Color
A temperature (+) red
B temperature (-) black
C ultrasonic (+) shield
D ultrasonic (-) clear