17
GOOD LABORATORY PRACTICE (GLP)
GLP is a set of functions that allows storage and retrieval of data
regarding the maintenance and status of the electrode.
All data regarding pH or Rel mV calibration is stored for the user to
review when necessary.
EXPIRED CALIBRATION
These instruments allow the user to set the number of days before the
next required calibration. This value can be set from 1 to 7 days. The
default setting is off (disabled). The “
CAL
” “
INTV
” tags will start blinking
to warn the user that the instrument should be recalibrated.
For example, if a 4 days time out has been selected, the instrument will
issue the alarm exactly 4 days after the last calibration.
If the expiration value is changed (e.g. to 5 days), then the alarm
will be immediately recalculated and appear 5 days after the last
calibration.
Notes
: • When the instrument is not calibrated or calibration is cleared
(default values loaded) there is no “expired calibration”, and
the display always shows the “
CAL
” “
INTV
” tags blinking.
• When an abnormal condition in the RTC is detected, the
instrument forces the “expired calibration” status.
pH CALIBRATION DATA
Calibration data is stored automatically after a successful calibration.
To view the pH calibration data, press
GLP
while in measurement mode.
The instruments will display the time (hh:mm) of the last calibration.
Use the
ARROW
keys to scroll through the calibration data:
• The date (yyyy.mm.dd).
32
PC INTERFACE
Data transmission from the instrument to the PC can be done with the
HI 92000
Windows
®
compatible software (optional).
HI 92000
also
offers graphing and an on-line help feature.
Data can be exported to the most popular spreadsheet programs for
further analysis.
To connect your instrument to a PC, use a standard USB cable connector.
Make sure that your instrument is switched off and plug one connector to
the instrument’s USB socket and the other to the USB port of your PC.
Note:
If you are not using Hanna Instruments
HI 92000
software,
please see the following instructions.
SENDING COMMANDS FROM PC
It is also possible to remotely control the instrument with any terminal
program. Use a standard USB cable to connect the instrument to a PC,
start the terminal program and set the communication options as follows:
8, N, 1, no flow control, 9600 baud rate.
COMMAND TYPES
To send a command to the instrument, follow the next scheme:
<command prefix> <command
>
<CR>
where:
<command prefix> is a 16 ASCII character
<command> is the command code.
Note:
Either small or capital letters can be used.
SIMPLE COMMANDS
RNG
Is equivalent to pressing
RANGE
CAL
Is equivalent to pressing
CAL
CFM
Is equivalent to pressing
CFM
UPC
Is equivalent to pressing the
UP
arrow key
DWC
Is equivalent to pressing the
DOWN
arrow key
LOG
Is equivalent to pressing
LOG
RCL
Is equivalent to pressing
RCL
SET
Is equivalent to pressing
SETUP
Notes:
• If the reading is not close to the selected calibration point,
“
WRONG
” tag will blink. Verify calibration condition or
contact your vendor if you can not calibrate.
• Pressing
CAL
key during temperature or mV calibration, the
instrument quits calibration mode and restarts to measurement
mode without memorizing calibration.
