Hach NA5600 sc Na+ Mode D'emploi page 24

Option
SET INTERVAL
SELECT CAL
CHANNEL
5.2 Do a calibration
Let the analyzer operate for 2 hours after initial startup (or storage) to become stable, then do a
calibration.
Over time readings can drift to higher or lower than they should be. For the best accuracy, calibrate
the analyzer at 7-day intervals (weekly).
1. Push cal, then select START CALIBRATION.
2. Select an option.
Option Description
AUTO CAL
Note: This option is only available if the analyzer has the auto calibration option.
MANUAL
Manually starts an auto calibration.
START
Important: Before an auto calibration is done, do the steps in
level of the overflow vessel
MAN Starts a 1-point manual calibration. When prompted, add 200 mL of the
OFFSET CAL calibration standard to the overflow vessel. The recommended standard is
100 ppb or 1000 ppb.
Note: Do not use a standard solution that is less than 100 ppb because it can quickly
become contaminated, which changes the concentration.
MAN Starts a 2-point manual calibration. When prompted, add 200 mL of each
OFFSET calibration standard to the overflow vessel. The recommended standards are
+SLOPE CAL 100 ppb and 1000 ppb.
Important: The difference in temperature of the two calibration standards must
not be more than ± 5 °C (± 9 °F). The second calibration standard must have a
sodium concentration that is 5 to 10 times more than the first calibration
standard (e.g., 100 ppb and 1000 ppb). A large difference between the sodium
concentration of the calibration standards is necessary to get an accurate
calibration.
Note: Do not use a standard solution that is less than 100 ppb because it can quickly
become contaminated, which changes the concentration.
5.2.1 Prepare calibration standards
To prepare a 100-ppb Na standard and a 1000-ppb Na standard to do a manual calibration, do the
steps that follow. All volumes and quantities used to prepare the calibration standard must be
precise.
Items supplied by the user:
• Volumetric flask (4x), 500 mL, Class A
• NaCl, 1.272 g
• Ultra pure water, 500 mL
• 1–10 mL TenSette pipet and tips
24 English
Description
Note: The SET INTERVAL option only shows when TIME BASE is set to HOURS.
Sets the time interval between calibrations. Options: 2 to 255 hours (default:
168 hours = 7 days). The recommended time interval between calibrations is
7 days.
Selects the channel used for calibrations (default: Channel 1).
Note: Do not select a channel that contains the symbol "~" (e.g., 4-~SAMPLE4).
Channels that contain the symbol "~" are not measured.
on page 22.
Adjust the water