Hach-Lange SD900 Basic User Manual - Manual (Page 21)

1. Push MENU.
2. Go to PROGRAM SETUP>RESTORE.
3. Select YES.
Start or stop a program
Use the RUN/HALT PROGRAM key to start or stop a program. Up to 12 user-defined start/stop
times/dates can be set. A program must be stopped before the program or system setup can be
changed.
1. Push RUN/HALT PROGRAM.
2. Select one of the options.
Option Description
Start Starts the currently loaded program. The status changes to RUNNING.
Halt Stops the program temporarily. The status changes to HALTED.
Resume The program resumes from the point at which it was halted. The status changes to
RUNNING.
Start over The program starts from the beginning. The status changes to RUNNING.
End program Stops the currently running program. The status changes to COMPLETE.
Manual operation
Use manual operation to collect a grab sample, move the distributor arm or operate the pump. For
additional information, refer to the expanded version of this manual.
Volume calibration
The sample volume can be calibrated automatically with the liquid sensor or manually. When the
liquid sensor is used for volume calibration, the sensor is adjusted to accurately measure all
programmed volumes. If the liquid sensor is disabled, the volume for samples, rinses and stormwater
must be calibrated manually.
For typical applications, tap water can be used for the volume calibration. If the sample composition
is significantly different from typical water samples, calibrate the sampler with the liquid to be
collected. All programs must be stopped before calibration.
Calibrate the liquid sensor
The accuracy of the liquid sensor varies with the type of liquid that is sampled. For example, the
volume of a highly turbid sample may not be as accurate as that of clear water. The liquid sensor can
be calibrated with the sample water to improve volume accuracy.
1. Put the intake tubing into the sample water.
2. Push MENU.
3. Go to PROGRAM SETUP>MODIFY SELECTED>LIQUID SENSOR>ENABLE to make sure that
the liquid sensor is enabled.
4. Go to SYSTEM SETUP>LIQ SENSOR CAL.
5. Select PERFORM CAL.
6. Select START. The pump operates in reverse to purge the intake tube. The pump then operates
in the forward direction.
7. Look at the sample flow in the intake tube to make sure that the sample goes through the liquid
sensor.
8. When the sample goes through the liquid sensor and no bubbles are present, push STOP. The
intake tube is automatically purged. The liquid sensor calibration is complete.
9. Select DONE to exit or REPEAT to do the calibration again.
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