6 measurement process, 1 smart rinse option – Hach-Lange POLYMETRON 9245 User Manual User Manual

Page 26

Advertising
background image

24

Analyzer Overview

3.6 Measurement process

The 9245 requires an on-line measurement time which defines the measurement time of the
sample, and how often the measurement values are stored in memory. Regardless of this value
the alarms, analog outputs and RS 485 serial communication output are updated regularly (see

Analyzer outputs on page 29

). The recommended (and default) value is 10 minutes, which will

ensure 3 months of data stored internally.

The smart rinse facility can be used for rinsing the measurement cell after a calibration, grab
sample or sensor reactivation. If used, a maximum rinse time must be entered.

3.6.1 Smart rinse option

The measurement cell is rinsed by the analyzer after a calibration, grab sample, or sensor
reactivation process and prior to resuming sample measurements. Set the smart rinsing
parameter to No (see

Measure steps on page 73

) for a fixed rinse cycle of 10 minutes or set to

Yes

to invoke the smart rinsing option which better guarantees the accuracy of measurements

after the rinsing cycle.

If the parameter is set to Yes, a maximum rinse time must be defined. To ensure a fast rinse the
recommended time is 60 minutes with a flow rate of 6 to 9 L/hour. During the rinse process, as
soon as the analyzer determines that measurements are stable it will revert back to sample
measurement mode. If there is an increase in the sodium concentration at any time, then after a
5 minute period the rinsing will be aborted and the analyzer will revert back to sample
measurement mode.

Figure 6 Rinsing process after a calibration, grab sample or sensor reactivation

Advertising