Metrohm 765 Dosimat - Manual (Page 25)

3.2 Diagnosis
765 Dosimat
21
3.2 Diagnosis
3.2.1 General
The 765 Dosimat is a very precise and dependable feeding instrument.
Thanks to its rugged construction, it is highly unlikely that external mechani-
cal or electrical influences will have any adverse effect on its functions.
Although a fault in the instrument can not be excluded with certainty, the
possibility is greater that malfunctions are caused by wrong operation or
handling, through improper connections and the operation with third-party
devices.
Whatever the case, it is always advisable to localise the fault with the diag-
nostic tests, which can be performed quickly and simply. The customer
need call Metrohm service only when the instrument really has a fault. Fur-
ther, he can use the results of the specific diagnostic function to provide the
service engineer with much more precise information.
In the case of inquiries, always quote the serial number on model plate
(see page 3), the program version (see page 18) and if applicable the error
message.
Procedure
The diagnostic menu listed in section 3.2.2 shows all components for which
detailed instructions (diagnostic steps) are available for checking the func-
tionality.
In the case of a possible malfunction, we advise you to perform either the
corresponding diagnostic step or all diagnostic steps as a routine check on
the instrument.
The reactions of the Dosimat to the instructions must be compared with the
descriptions in the diagnostic step. If the Dosimat do not show the ex-
pected reaction ("No" case), the appropriate diagnostic step must be re-
peated to exclude operating errors. However, it is highly probable that re-
peated wrong reactions indicate a malfunction.
Equipment required:
3.496.0070 Dummy-exchange unit (or exchange units if possible with different cylinder
volumes).
6.2107.000 Push-button cable or ordinary test lead with 4 mm banana plugs
6.2149.000 Keyboard
3.496.8360 Test plug
-.---.---- Stop watch or watch with second hand.
-.---.---- Voltmeter (perhaps a calibrated recorder)