6
temperature coefficient at a specific
reference temperature. Also, note that
increasing the magnitude of the calibration
tolerance can decrease the accuracy of the
instrument This option should be the last
choice for calibration difficulty. The calibra-
tion tolerance can be set from 1 (represent-
ing the most stringent standards, the factory
standards used for calibrating with distilled,
deionized water and NIST certified calibra-
tion solutions) to 50 (the loosest standard).
Invert Display
Default Setting: Off
The display screen may be displayed in either a dark
background with light lettering or a light
background with dark lettering. Instrument
performance is not affected by this feature.
Language
Default Setting: English
Screens can be displayed in English, Spanish, French, or
German. Note that the custom channel names and unit
definitions will appear as entered in the custom channel
program.
Time and Date
The Reichert AR6 can track the clock time in
either standard 12 hour am/pm time or
military time. The AR6 is Year 2000
complient. The date may be set in Month/
Day/Year format
Display Time
Default Setting: Off
Activating this function will display the exact time each
reading is taken. This time will remain until another
reading is taken.
Restore Defaults
Default Setting: Off
This allows the user to restore all settings to the factory
defaults when SETUP is pressed again. This does not
erase custom channels or calibration history.
Calibration History
Default Setting: Off
Switching this setting to “on” will display the previous 512
calibrations. Some parameters extend beyond the right
hand portion of the display. To see these, simply press
the MODE button until the parameter desired is visible.
The calibration history may be downloaded to a computer
through the serial port by use of a standard communica-
tions program and entering the command “calhis”.
Precision
Default Setting: On
ON - Instrument reads refractive index to the 5th decimal
place (0.00001) and % Solids to the 2nd decimal place
(0.01). OFF - Instrument reads refractive
index to the 4th decimal (0.0001) and %
Solids to the 1st decimal (0.1) place.
Password
Default Setting: Off
Password protection can be used to secure options once
they are set Turning password ON and pressing SETUP
displays the “Enter New Password’ screen (see Screen
3). Use the arrow keys to enter a 3 digit numerical pass-
word. Entering 000 cancels the setting and turns the
password protection off. Press SETUP to exit the “Enter
New Password’ screen. A second screen confirming your
choice of password will appear. Press SETUP to cancel
or READ to accept the new password. Once a password
is entered the instrument will prompt the user for the
password each time the Set Up screen is
accessed.
Sound
Default Setting: Off
ON - Chime sounds when key is pressed or a reading or
calibration is displayed. OFF - Sound is turned off.
Once all operational parameters have been set using the
Set Up screen press SETUP to return to the start
screen (Screen 1).
3. Calibration and Sample Reading
NOTE: These instructions assume the sample well is
clean and dry prior to starting. The sample well should
also be completely cleaned between samples. Clean with
distilled water, soapy water, methanol or isopropyl alcohol.
Dry with a soft cloth.
These instructions assume the one point calibration
(default) was chosen in set up.
See “Multipoint Calibration” for instructions for the
multipoint calibration.
From the start screen press INITIATE. The instrument
screen will blank and the words “Initiating Please Wait’
will appear. During the initiating sequence the lamp
brightness is set to an optimum level. When the
instrument has finished initiating the “Initialization
Complete” screen (screen 4) will appear.
Follow the on screen instructions to add distilled water to
the sample well, allow the temperature to equilibrate and
press CALIBRATE.
The instrument will display a refractive index reading
between 1.33400 (prism temperature of 10°C) and
1.33059 (prism temperature of 40°C). A typical reading
would be 1.33299 at a reference temperature of 20°C
(see screen 5). Press the SETUP key to exit this screen.
At this time the MODE key can be used to display the
reading in any of the 4 instrument modes:
Index The non-temperature compensated refractive index
reading.
Index-TC: The temperature compensated refractive index
reading. For distilled water this value should be 1.33299
±0.00002.
