Metrohm 711 Liquino - Manual (Page 158)

6.5 Diagnosis
711 Liquino, Instructions for use 152
6.5.4 Check working memory (RAM)
This diagnosis step carries out a non-destructive test of the whole of the
RAM contents (working memory).
•
Prepare instrument for diagnosis (see Sect. 6.5.3).
• If necessary press key <9> several times until

di agnosi s
>RAM t est
• <ENTER>
 The test proceeds automatically. If no faults are found the display
shows:

>RAM t est
RAM TEST OK
• The test is exited by pressing the <STOP> key.

di agnosi s
>di spl ay t est
6.5.5 Check display
This diagnosis step allows the functioning of the LEDs and the display to
be checked.
•
Prepare instrument for diagnosis (see Sect. 6.5.3).
• If necessary press key <9> several times until

di agnosi s
>di spl ay t est
• <ENTER>
 When the <ENTER> key is pressed the program automatically car-
ries out a test run for an optical check of the LEDs and display.
a) The LEDs DOS 1, DOS 2, DOS 3 and DOS 4 are switched off and on
several times in sequence.
b) The background lighting is switched off and on several times in se-
quence.
c) Switch-on test pattern appears (each pixel is active).
d) Both display lines are deleted.
e) Both display lines are written in sequence with the characters “
#“, “H“
and finally with “ I “.
f) Both lines are written from right to left with the endless text
“ 0123456789ABCDEFGHI JKLMNOPQRSTUVWXYZ“.
• The test run can be interrupted by pressing any key (except
<STOP>) and then restarted.
• The test is exited by pressing the <STOP> key twice.

di agnosi s
>di spl ay cont r ast t est