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Geotechnical Instruments
CODAOM002 Iss.06
3.3 Alarm
Settings
Whilst in the main gas screen the analyser monitors the gases levels and will alarm if any of the pre-set
levels are triggered. The alarm can be set as either latching or non latching.
3.3.1 Setting alarm limits
From the main menu press key ‘2-Alarm settings’ to display the alarm screen. Then press key ‘2-Alarm
levels”. This screen shows the existing alarm levels for each of the four gas type. Use keys ‘1-4’ to select
the required gas and follow the on-screen instructions. Leading zeros should be entered where necessary
i.e. 0999ppm.
3.3.2 Setting alarm mode
To set the alarm to either latching or non latching mode, select option ‘2-Alarm settings’ from the main
menu. Then use key ‘1’ to toggle alarm latching ON or OFF. Exit from this screen by pressing key ‘0’.
3.4 Storing and reviewing readings
The analyser allows readings to be stored at preset intervals. The logged readings can then be reviewed
on the screen. This facility allows the operator to review gas concentrations before an alarm condition to
see if they are acceptable. Each logged reading contains an ID code (fixed at time of manufacture), a
time/date stamp and readings for each of the four gases. From the main menu press key ‘4-Data Logging’
this displays the data logging menu. From the logging menu you can select from the following four
options:-
1-Logging Options
2-View Data
3-Clear Memory
4-Download data
3.4.1 Logging
Options
This is the principle control menu for setting or reviewing all data logging options. From here the operator
can check or set the instruments internal clock. It is important that this is set correctly as every reading
logged includes the time and date at which it was recorded. To do this press key ‘1-Check time/date’ and
follow the simple on-screen instructions. The logging interval time can also be set between 1 and 60
minutes. From the logging menu press key ‘2-Set interval’ and follow the instructions.
The final option on this menu allows the user to start and stop data-logging. Upon return to the main
reading screen the word ‘LOGGING’ is displayed in-place of the ‘9-Batt’ text (although key ‘9’ still works).
Once enabled the analyser continues to log at the requested interval until stopped by the operator.
It is important that data-logging is stopped before viewing logged data. It is possible to corrupt stored
readings if this options are used whilst still logging.
3.4.2 View
data
View data allows the operator to review previously logged data. Using this option logged data can be
viewed on the screen or output to printer via RS-232. When viewing data use the scroll keys (1 and 6 )
to step through the readings. Holding down a key speeds up the viewing process.
The print option can output formatted ASCII data via the instruments RS-232 port directly to a suitable
printer or PC running suitable software (i.e. Windows HyperTerminal). To receive data the printer or PC
should be set to 2400baud, 8 data-bits, 1 stop-bit with No parity. Hardware handshaking should be
enabled when downloading large amounts of data.
3.4.3 Clear
Memory
The analyser can store up to 600 data sets (readings). The clear memory option allows the operator to
view the number of free readings available and to clear them if required. Once cleared the readings are
permanently deleted and cannot be recovered. Therefore, before the readings can be cleared the user
must first acknowledge a warning and enter a pass-code as directed.