4 diagnosis, 1 general – Metrohm 774 Oven Sample Processor User Manual
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6.4
Diagnosis
774 Oven Sample Processor, Instructions for use
143
6.4 Diagnosis
6.4.1 General
The 774 Oven Sample Processor is a very precise and reliable unit. Thanks
to its rugged construction, its functions can hardly be impaired by external
mechanical or electrical influences.
Even though the possibility of a fault occurring in the unit can never be en-
tirely precluded, there is a greater possibility of malfunctions occurring as
the result of operating errors or incorrect connections and operation with
third-party equipment.
At all events, it is advisable to localise the fault or error using the diagnosis
utility which can be run quickly and simply. This means that you do not
need to call your Metrohm servicing technician unless an actual fault or er-
ror has occurred in the unit. In addition, the results of the specific diagnostic
functions provide better information for the servicing technician.
Should you have any queries, please always state the serial number (rear
side of the unit, see Page 5) and program version (see configuration, Page
63) and, possibly, the text on the error or fault display.
Procedure
The following test list lists all components for which detailed instructions (di-
agnosis steps) exist in order to check their operability.
If an error occurs, we recommend that you follow the instructions of the cor-
responding diagnosis step or run through all diagnosis steps as a routine
check of the unit.
The unit's responses to the instructions must be compared with the descrip-
tions in the diagnosis step. If the unit does not show the expected response
("No"), repeat the corresponding diagnosis step in order to exclude the pos-
sibility of operating errors. Repeated incorrect responses do, however, indi-
cate a fault with a high probability.
Components
See Chapter
Main memory (RAM)
Display
Keypad
Remote
RS 232
External bus
Beeper
Rack code
Required equipment:
Required only if RS232 or Remote are to be checked:
Test connector 3.496.8550 (connected to socket ‘Remote’)
Test connector 3.496.8480 (connected to socket ‘RS 232’)