www.madur.com
Manual
GA-21Plus
2.4. Service intervals
The parameters of the electrochemical cells change with time, and therefore it is
necessary to carry out a service periodically. This service should include re-calibration of
the gas sensors using test gases. The recommended service interval is 800 operating
hours or 6 months, whichever comes first. The analyser is fitted with an operating hour
counter and automatically shows when a service is necessary.
The operating time and the number of hours until the next service are shown in
MENU->OPTIONS->madur
SERVICE
->
DEVICE INFO
.
2.5. Errors during operation
The analyser checks all circuitry continuously. Should an error become evident,
then this is signalled acoustically and by the message "ERROR" on the screen. The error
can be found shown on the screen
MENU->OP
TIONS
->madur S
ERVICE
->
CONTROL
LIS
T
.
2.6. Switching off after use
The operating life of the electrochemical cells is dependent on the usage of the
instrument. The wear and tear on the cells is greater when the cell is exposed to the gas
for longer or the concentration is higher. The gas cell is hence "used up" during measure -
ments.
Info:
For this reason, the analyser should not be switched off until all the
gas tubing has been completely cleared of flue gases and the gas
cells have been purged with fresh air for several minutes.
The
GA-21
plus
will not normally allow the instrument to be switched off if there
are still traces of flue gas in the system. The analyser will continue to operate until the
signals from the gas cells are nearly zero. This activity is shown by the message "VENT-
ILATION REMOVE PROBE FROM FLUE".
The [OFF] key must be pressed twice to switch the instrument off completely.
Pressing the key once will put the analyser in the standby mode and the instrument will
remain in this mode until it is activated again by pressing "C" or switched off completely.
6
