Metrohm 788 IC Filtration Sample Processor - Manual (Page 146)

6 Appendix
788 IC Filtration Sample Processor
138
6.3.3 Replacing the pump tubing
Pump tubings are consumable material with a limited lifetime and
should be replaced at regular intervals (approx. every 2 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 correctly
set as described in section 2.3.9. If the pump is to remain switched off
for a lengthy period of time the tubing cartridges should be raised
completely by loosening snap-action lever 16 16 16 16 on the right-hand side
(the pre-set contact pressure remains unchanged).
To replace a pump tubing proceed as follows:
1 Remove old pump tubing
x Press contact pressure lever 18
18 18 18 on the tubing cartridge down
as far as it will go.
x Release tubing cartridge 14
14 14 14 from holding clamp 17 17 17 17 by press-
ing down snap-action lever 16 16 16 16 and remove from mounting pin
13 13 13 13 at the 788 IC Filtration Sample Processor (see Fig. 1).
x Remove old pump tubing.
2 Insert new pump tubing
x Insert the new pump tubing 10
10 10 10 (6.1826.070) or 11 11 11 11
(6.1826.030) in the tubing cartridge as shown in Fig. 10. The
stopper 43 43 43 43 must click into the corresponding holder on the
left-hand side of the tubing cartridge.
x Place the tubing cartridge on mounting pin 13
13 13 13 and press
down on the right-hand side until snap-action lever 16 16 16 16 clicks
into position on holding clamp 17 17 17 17. Take care that no kinks are
formed in the pump tubing.
3 Set contact pressure
x Press contact pressure lever 18
18 18 18 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.
The 6.1826.0X0 pump tubing is made of PVC and must not be used
for rinsing with solutions which contain acetone. In such cases, rinse
with different pump tubing or a different pump.