HF scientific Micro200BW Turbidimeter - 0 -1000 NTU - Manual (Page 32)

Page 18
MICRO 200 BW 0 - 1000 NTU (5/05)
Rev. 3.1
c. Calibrate 0 - 1000 NTU
This is the turbidity calibration menu.
Sensor Calibrate is provided to adjust the sensor output for variations in lamp intensity. WHEN YOU PERFORM A SENSOR
CALIBRATE YOU MUST HAVE A 1000 NTU STANDARD IN THE WELL OR YOU MAY GET A SENSOR FAIL
MESSAGE.
F1, F2, F3 & F4 are selected calibration points which are used to calibrate the analyzer to the sensor. Any combination may
be used, however, the stated accuracy will not be achieved without using all four points. The analyzer uses the calibration values
to linearize the readings in this range. The recommended step-by-step procedure is on page 29.
Caution: Do not press F1-F4 unless the indicated standard is in the optical well.
The calibration points are shown on the left side of the screen and are selection options. The right side of the screen shows the
stored real frequency for each calibration point.
In the center of the screen are two numbers. The top number shows the current real frequency reading (decimal adjusted). The
lower number shows the corrected or linearized frequency. In most instances the numbers on this screen can be ignored. They
do, however, serve as a useful diagnostic tool.
See page 28 for complete step-by-step instructions.
Selection Options:
F1: Stores the standardize frequency
F2: Stores the 100 NTU frequency
F3: Stores the 400 NTU frequency
F4: Stores the 1000 NTU frequency
F5: Performs a sensor calibration with 1000 NTU in well
F2
F3
ALARM
F5 F4
MENU
F1 Ш.Ш2NTU Ш.Ш227
1ШШ.ØNTU 18Ш.6
4ШШ.ØNTU 4Ш2.5
1ШШШ.ØNTU 1ШШШ.Ш
Calibrate
Ш4Ш26 Hz
(Current Frequency)
4Ø2.6 NTU
(Current Reading)
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