Turbidity Test with LaMotte 2020e Turbidimeter

Note:  Instruments are calibrated before each use.

Calibration

1.  Press ON to turn the meter on. 

2.  Press OK to select measure.

3.  Fill pre-cleaned sample cell with DI water to use as a blank.  Pour down the sides of the tube to avoid creating bubbles.  Wipe down sides to remove fingerprints and liquid with a Kim wipe. 

4.  Insert blank sample tube in meter with the notch on the tube lined up with the arrow on the meter.  Close the lid.

5.  Press OK to select Scan Blank.  Remove tube.

6.  Fill a second pre-cleaned sample cell with the 10.0 NTU standard solution to the fill line.  Pour down the sides of the tube to avoid creating bubbles.  Cap the tube and wipe it for fingerprints and liquid. 

7.  Insert sample cell in the meter, lining up the notch on the tube with the arrow on the meter.  Close the lid. 

8.  Press OK to Scan Sample.  Observe the result versus the standard.

9.  Press ↓ and then press OK to Calibrate.

10.  Use the ↑ and ↓ keys to change the highlighted digits on the display to match the known standard.  Press OK to accept a digit and move down to the next digit.

11.  Press OK to accept the calibration and move on to reading samples.

Measurement

1.  Turn meter ON.  Press OK to select Measure.

2.  Use the sample cell marked DI (distilled water) as a blank. 

3.  Dry the tube with a Kim wipe to wipe away finger prints and liquid.

4.  Place sample cell in the meter with the notch on the tube lined up with arrow on the meter.

5. Press OK to select Scan Blank.

6.  Place the water sample to be measured on the stir plate, turn it on to stir, and place a stir bar in the sample.  Let the sample mix before pouring it into a sample cell.  The stir bar can be removed from the cup using the big red magnet.

7.  Fill a clean sample cell to the fill line with the sample to be tested.  Pour down the sides of the sample cell to avoid creating bubbles.  Cap the tube and wipe it with a Kimwipe to remove

fingerprints and liquid. 

8.  Insert the sample cell into the instrument, lining up the notch on

 the tube with the arrow on the instrument.  Close the lid. 

9.  Press OK to select Scan Sample.  Record results.

10.  Discard the water into the waste container and rinse the sample cell three times with DI water.  The same sample cell can be used for all the samples.

10.  Repeat steps 6-8 for each sample.  It is not

necessary to scan a new blank for each new sample.

11.  Discard all used water into the waste container provided.

 Rinse the sample cells three times with distilled water between samples and when finished.