Hach-Lange 2100 AN IS Laboratory Turbidimeter User Manual - Manual (Page 39)

Configure the data recorder output
Note: The recorder minimum and maximum values are selected independently for
each measurement mode. When the measurement mode changes, the previous
settings are automatically used.
1. Push SETUP. The SETUP light turns on.
2. Use the arrow keys to select an option:
Option Description
14 Sets the minimum value of the recorder output for the current
measurements units.
15 Sets the the maximum value of the recorder output for the current
measurement units.
16 Moves the recorder minimum output to calibrate the recorder.
17 Moves the recorder full-scale output to calibrate the recorder.
18 Sets the recorder to zero scale.
19 Sets the recorder to half scale.
20 Sets the recorder to full scale.
3. Push ENTER.
4. If option 14 or 15 was selected, move the decimal point to the correct
location using the right arrow key, then push ENTER.
5. Use the arrow keys to change the value.
6. Push ENTER.
7. Push SETUP.
Advanced operation
Calibrate the turbidimeter with formazin standards
The instrument may be calibrated using prepared formazin standards
made from 4000-NTU formazin stock solution. Refer to
Accessories
on page 46.
Note: Use recently prepared formazin standards to get the accuracy specifications
for turbidity in
Specifications on page 5.
Prepare formazin standards
For the best accuracy and long-term data comparability, use formazin
stock solution from Hach to make formazin standards.
Note: As an alternative, a 4000-NTU formazin stock solution that is prepared by
the user may be used to make formazin standards. Refer to
Making 4000-NTU
formazin stock solution on page 40.
Prepare formazin standards immediately before calibration in an
environment that is at the same ambient temperature as the instrument.
Discard after use.
Refer to
Table 6 for the procedures to make the recommended
calibration standards.
Table 6 Formazin standard preparation
Standard Step 1 Step 2 Step 3
20 NTU Add 100 mL of dilution
water to a clean 200-
mL Class A volumetric
flask. Refer to
Prepare
dilution water
on page 23.
With a TenSette ®
Pipet, add 1.00 mL
of well-mixed 4000-
NTU formazin stock
solution to the 200-
mL flask.
Dilute to the mark
with dilution water.
Stopper and mix.
200 NTU Add 50 mL of dilution
water to a clean 100-
mL class A volumetric
flask. With a TenSette 1
Pipet, add 5.00 mL
of well-mixed 4000-
NTU formazin stock
solution to the 100-
mL flask.
Dilute to the mark
with dilution water.
Stopper and mix.
English 37