Metrohm 700 Dosino - Manual (Page 42)

3. The Dosino in practice
700 Dosino, Instructions for Use
36
Tubing not completely filled during PREP.
Possible cause:
• Incorrect parameters have been defined for the dosing
unit.
⇒ Correct the tubing lengths and diameters; please refer to the
‘Instructions for Use’ of the control instrument.
Tubing not completely emptied during EMPTY.
Possible cause:
• Incorrect parameters have been defined for the dosing
unit.
⇒ Correct the tubing lengths and diameters; please refer to the
‘Instructions for Use’ of the control instrument.
Wrong volume is dosed.
Possible cause:
• Dosing unit mounted incorrectly or wrongly assembled.
⇒ Remove dosing unit and put it back on again.
⇒ Check whether the nominal volume on the housing coincides
with the effective cylinder volume.
Dosing does not take place.
Possible cause:
• Blocked tubing connections or dosing unit wrongly as-
sembled.
⇒ Check whether the dosing tip is blocked.
⇒ Check whether the dosing port has been closed with a thread
stopper.
⇒ Check whether Port 0 has been closed with a thread stopper
(vacuum in storage bottle!). Port 0 must be open to compen-
sate the pressure.
⇒ Remove dosing drive and check whether the drive push rod
engages the dosing piston. The piston peg must be flush with
the upper side of the housing, see page 19.