10 exchanging the pump tubing – Metrohm 790 Personal IC User Manual
Page 176
5.2 Maintenance and servicing
790 Personal IC
167
5.2.10 Exchanging the pump tubing
The pump tubings used by the peristaltic pump are consumable mate-
rial with a limited lifetime and should be exchanged at regular intervals
(approx. every 4 weeks under continuous use).
The working life of pump tubing depends to a considerable extent on
the contact pressure. This is why the contact pressure must be cor-
rectly set as described in section 2.9.2. If the pump is to remain
switched off for a lengthy period of time the tubing cartridges 40
40
40
40 should
be raised completely by loosening the snap-action lever 43
43
43
43 on the
right-hand side (the set contact pressure remains unchanged).
As the pump is always operated on the same side, the 6.1826.060
Pump tubings supplied can be used on both sides. To exchange a
pump tubing proceed as follows:
1 Remove old pump tubing
• Press contact pressure lever 41
41
41
41 on the tubing cartridge 40
40
40
40
down as far as it will go.
• Release tubing cartridge 40
40
40
40 from holding clamp 42
42
42
42 by press-
ing down snap-action lever 43
43
43
43 and remove from mounting
pin 45
45
45
45 (see Fig. 15).
• Remove old pump tubing 74
74
74
74 or 75
75
75
75.
2 Insert new pump tubing
• Insert the new pump tubing 74
74
74
74 or 75
75
75
75 in the tubing cartridge
40
40
40
40 as shown in Fig. 14. The white-yellow stopper 76
76
76
76 must
click into the corresponding holder on the left-hand side of
the tubing cartridge.
• Place the tubing cartridge 40
40
40
40 on mounting pin 45
45
45
45 and press
down on the right-hand side until snap-action lever 43
43
43
43 clicks
into position on holding clamp 42
42
42
42. Take care that no kinks are
formed in the pump tubing.
3 Set contact pressure
• Switch on peristaltic pump.
• Press contact pressure lever 41
41
41
41 upwards until the solution
just starts to be drawn in. Then press contact pressure lever
upwards until it clicks once more to obtain optimal contact
pressure.
• Switch off peristaltic pump.