Hach 900 MAX manual Section - Sample Volume, Intake Rinses, Sample Retries

Section 3

Step 8 - Sample Volume

Note: The minimum sample volume is ten milliliters.

When multiple bottles are selected in Bottle Per Sample mode all bottles in a subset receive a full sample volume. The volume is not divided among

the bottles.

8-A.Enter the desired volume of each sample using the numeric keypad. Press ACCEPT to continue to Intake Rinses.

11:00 AM 21 - APR - 01		SAMPLE VOLUME
ACCEPT
	SAMPLES VOLUME:
BACKUP	______	CLEAR
		ENTRY
	ENTER: 10 — 9999

Step 9 - Intake Rinses

9-A.Enter number of rinses using the numeric keypad.Press ACCEPT to continue to Sample Retries.

11:00 AM 21 - APR - 01

INTAKE RINSES

ACCEPT
	INTAKE RINSES:
BACKUP	0	CLEAR
		ENTRY
	ENTER: 0 — 3

Up to three intake rinses are enabled per sample cycle. After the sample cycle’s initial purge has been completed, the sample liquid is drawn in until it reaches the liquid sensor. The pump stops and purges the line before any liquid enters the bottle. This is repeated up to three times before the actual sample is taken and the line purged for the final time during that cycle.

Intake rinse can prevent cross contamination of samples. When the line is purged at the end of each sample cycle, a few droplets of sample liquid may cling to the inside walls of the tubing and the droplets are drawn in with the following sample. Intake rinses will condition the intake line with a source liquid that minimizes contamination from the previous sample.

Step 10 - Sample Retries

Note: Excessive intake tube line lengths combined with multiple Intake Rinses and Sample Retries can increase the pump tube and drive train wear. Locate the sampler as close to the sample liquid source as possible to minimize wear and maintenance requirements.

10-A.Enter the number of Sample Retries using the numeric keypad. Press ACCEPT to continue to Site ID.

Up to three sample retries are enabled per sample cycle. After the initial purge is completed, the sample liquid is drawn until it reaches the liquid sensor. If the sample liquid does not reach the sensor within a reasonable time (determined using the tubing length), the sample attempt is aborted, a purge is initiated and the first of up to three sample retries is attempted.

After three attempts and no sample liquid has been collected, the cycle is aborted, a Missed Sample is reported to the Sample History Log, and the sampler begins a new sample interval.

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Basic Programming Setup	8990startup.fm