Hach POLYMETRON 9245 Manuel D'utilisation De Base page 17

Test
This option allows you to enter a value into the mA field. Press the Enter function key to force this
value on all the analog outputs. The value can then be verified with the use of a multimeter
connected to the analyzer.
RS485 (or PROFIBUS)
Note: If the PROFIBUS option has been installed, then the menu option will show PROFIBUS rather than RS485,
and the PROFIBUS parameters will need to be installed.
1. Select the RS485 option to set up the parameters for the communications protocol.
2. Press the Enter function key to accept each data element.
3. On completion, press the Esc function key to return to the user setup screen.
Sample channels
Select the SAMPLE CHANNELS option to set up the channel parameters.
Channel activation
Using the Up and Down Arrow keys, define whether the channel is active (Activ) or inactive
(Inactiv).
Sequence
The default sequence should be left unchanged.
Channel names
Define the name of the channel with free-format alphanumeric text up to a maximum of 8 characters.
CALIBRATION
The instrument cannot be calibrated until at least one complete measurement cycle has been
successfully performed. An attempt to calibrate the instrument before this will result in a "Not
authorized" message being displayed.
In order to obtain accurate measurement results, the analyzer should be calibrated on a regular
basis. Two basic methods of calibration are available:
• Automatic calibration - Parameters can be set up so that the analyzer will perform a calibration
automatically on pre-defined days at a pre-defined time (see
on page 19). This type of calibration is always done using known calibration solution
concentrations.
• Manual calibration - The user can manually perform a calibration on an ad-hoc basis.
Note: Before starting a calibration It is very important to ensure that the Reactivation Frequency parameter (see
Reactivation frequency on page 15) is greater than zero. If set to zero, the electrode reactivation process will not
take place during calibration and as such the measurement results may well be out of limits.
Calibration solution concentrations
The maximum concentration value for any calibration solution cannot be greater than 2000 ppm. Any value
superior to this is outside the analyzer specifications and cannot be processed.
Manual calibration
For a manual calibration, the calibration solutions must be between 100 ppb and 2000 ppm and
must respect the following rules:
• LOW CAL SOL must be ≥ sample concentration of Na
• HIGH CAL SOL = (LOW CAL SOL x 10)
Example 1: sample concentration of Na
N O T I C E
+
and a minimum of 100 ppb
+
= 20 ppb
Automatic calibration setup
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