HF scientific Micro100 Laboratory Turbidimeter - Manual (Page 11)

Micro 100 (5/10) Page 5
Rev. 3.3
7. If you are measuring and comparing more than one sample, pressing the enter key will display
the latest reading (displayed on the lower row of the display). In addition, if you have selected
printer output in the customer setup section pressing the enter key will output data to the
RS232 port.
8. Repeat steps 2 through 7 for all of your samples.
NOTE: The Micro 100 may display - - - for a few seconds while it determines the correct reading.
NOTE: An indication of (over-range) in the upper row of the display indicates that
the standard in the sample well is higher than 1000 NTU.
WARNING: NEVER pour liquid directly into the sample well of the MICRO 100, always use a
cuvette. The MICRO 100 will accurately measure the turbidity of a sample using only
cuvettes with the black light shield on the cuvette (provided by HF scientific) or the
optional pour through assembly.
4.2 Pour Through Sample Measurement (Optional Accessory)
Install the pour through assembly and index it according to the instruction sheet that accompanies the
assembly. The following steps describe how to measure the turbidity of a sample using the MICRO 100
fitted with the optional pour through assembly:
1. Turn on the MICRO 100. The instrument will be in the normal automatic mode (the "AUTO"
block should be illuminated). Allow instrument to warm up for at least 30 minutes.
2. Sample approximately 500 ml of the process stream as you would normally do for turbidity
measurement.
3. Pour the complete 500 ml sample into the pour through assembly. Record the turbidity of the
sample displayed after the entire 500 ml sample has been poured into the assembly and the flow to
drain has ceased, and after the reading has stabilized.
4. If you are measuring and comparing more than one sample, pressing the enter key will store
the reading (displayed on the lower row of the display). In addition, if you have selected printer
output in the customer setup section pressing the enter key will output data to the RS232 port.
5. Repeat steps 2 through 4 for all of your samples.
The sample cuvette used in the pour through assembly is identical to the two standard sample cuvettes
supplied with the MICRO 100. Clean the cuvette on a periodic basis according to your experience with
the type and turbidity of the sample found in your facility.
5.0 Calibration Procedures
The instrument was calibrated and tested prior to leaving the factory. Therefore, it is possible to use the
instrument directly out of the box. Under normal conditions, re-calibration is recommended at least once
every three months
1 .
1
The EPA recommends that on-line turbidimeters be calibrated with a primary standard at least once
every three months if they are to be used for EPA reporting.