1. Samples should be collected in a clean glass or polyethylene container.

2. Samples should be analyzed as soon as possible after collection.

3. Discard tubes that are badly scratched.

4. Gently mix sample by inverting before taking a reading but avoid introducing air bubbles.

5. Turbidity readings will be affected by electric fields around motors.

6. Carbon in the sample will absorb light and cause low readings.

7. Observe shelf life recommendations for turbidity standards.

8. The turbidimeter should be placed on a surface free from vibration. Vibrations can cause high readings.

9. Excessive color in a sample will absorb light and cause high readings. The user should verify if a certain level of color will cause a significant error at the level of turbidity being tested.

Problem	Check	Action
No Power	Battery	Replace
	AC Adapter	Plug in
	AC Wall Outlet	Verify power source
Suspect Calibration	Check calibration with standards	Use new standards
	Verify standards with Formazin	Run alternate test with Formazin
	Verify with another meter	Check other meter calibrations
	Check tube alignment	Re-align tube
	Check sample tubes for dirt and scratches	Check, clean and/or replace if necessary
	Check to see if internal meter components are wet	Always dry tubes before inserting. Examine chamber for visible moisture.
	Reset meter to factory calibration	With meter off, hold down key and press READ
	Battery	A fresh battery should be installed at all times, even when using the power adapter. This will ensure that the meter will power down properly and the calibration will not be lost.
Er1	Very low battery	Change battery
Er2	Over range	Dilute sample
Er3	Burnt out bulb or misaligned tube	Check alignment
BAT	Low Battery	Change battery

Notes:

1. If the battery voltage is very low, the meter may read Er3 rather than Er1. Replace battery with new Duracell 9V battery.

2. If unable to calibrate meter to standard solutions, try resetting the meter to factory calibration. To reset the calibration to factory settings: with the meter off, press and hold the DOWN button and push READ. The meter will turn on and the calibration will be reset.

Replacing the Battery

The LaMotte 2020 uses a standard 9-volt alkaline battery that is available worldwide. A fresh battery should be installed at all times, even when using the power adapter. This will ensure that the meter will power down properly. The battery compartment is located on the bottom of the case. To replace the battery:

1. Open the battery compartment lid

2. Remove the battery and disconnect the battery from the polarized plug.

3. Carefully connect the new battery to the polarized plug and insert it into the compartment.

4. Close the battery compartment lid

Replacing the Lamp

The tungsten lamp included with the model 2020 has a life of approximately 800 hours. If the display becomes unstable when using LaMotte AMCOTM standards, call LaMotte Company for a return authorization number to have the lamp replaced and have the unit examined.