Biogas Operating Manual
Page 8
Geotechnical Instruments (UK) Ltd
BMUK0001 / Issue 1
3.10 Clear Reading Memory
Selected via the main menu the clear memory screen enables the user to check how many readings
have previously been taken and clear them if necessary. Clearing readings is a simple process just
follow the on-screen instructions. Before readings are actually deleted a caution is displayed as once
readings have been deleted they cannot be recovered. The Biogas
instrument can store up to 100
readings. Once the reading memory is full it is not possible to store any more readings. When the
store key is pressed the instrument will show a brief message stating that the memory is full.
3.11 View Readings
Stored readings can be viewed via the main menu. The
cursor keys can be used to scroll through
the available readings either forwards or backwards. One complete reading is displayed on each page
using a similar layout to the main reading screen.
3.12 Adjust Contrast
The Biogas
instrument automatically adjusts the screen contrast to maintain a normal viewing
contrast according to the current display temperature. Manual adjustment of the contrast is also
available and can be carried out with using the
cursor keys. The manually set contrast setting is
retained when the read-out is switched off and therefore may require re-setting when next switched on.
3.13 Instrument Settings
The instrument settings screen allows the user to configure the reading sequence and various other
options as desired. When selected the current settings are displayed. These include the following
parameters:
•
Purge Time
•
Prompt for ID reading
•
Prompt for temperature reading
•
Flow device
•
Pipe and Orifice diameters
•
Units of measurement
Pressing the
key brings up a sub-menu where you can select the parameter to be edited. Most of
the parameters are self-explanatory. There are limits on the size of pipe and orifice diameters. These
can be affected by the units of measurement currently selected. Also, the ratio of the orifice to pipe
diameter cannot exceed 75% and the orifice cannot be larger than the pipe diameter.
3.14 Set Time / Date
Selected via the main menu the set time/date screen enables the user to check or set the internal
clock. This value is appended to every stored reading. It is also displayed in the top-left corner of the
main read screen. Setting the clock is a simple process - just follow the on-screen instructions. It is
also possible to switch the date format between dd/mm/yy and mm/dd/yy formats if required. Please
note the clock will need to be manually adjusted to cope with daylight saving changes or changes when
crossing time zones.
3.15 Set Gas Alarms
The Biogas instrument has the facility to set rising or falling alarms for the three main gas channels
(CH
4
, CO
2
and O
2
). Once enabled these alarms become active in the main reading screen. If an alarm
is triggered a flashing bell symbol is displayed next to the appropriate gas value and a beeper is
sounded until the gas level has dropped below the trigger point.
