Metrohm 838 Advanced Sample Processor Installation Instructions - Manual (Page 30)

24 838 Advanced Sample Processor, Installation
1 Detaching the tubing cartridge(s)
Detach the tubing cartridge(s) 48 by pressing in the snap-
action lever 51 on the retaining bracket and disengage it
(them) from the retaining cam 53.
2 Fitting the pump tubing
Press the contact pressure lever 49 of the tubing cartridge(s)
fully down.
Insert one length of pump tubing into the tubing cartridge(s)
as shown above.
The stopper 57 must engage in the corresponding fixture at
the top of the tubing cartridge.
3 Fitting the tubing cartridge(s)
Engage the tubing cartridge(s) in the retaining cam 53 and
press it (them) down until the snap-action lever 51 on the re-
taining bracket 50 engages, see Figure 7. Ensure that the
pump tubing is not kinked.
4 Fitting the coupling on the pump tubing
Connect the PEEK coupling 55 to the aspiration end of the
pump tubing 56 (see illustration below).
Fit the PEEK coupling 58 with 6.2744.160 tubing guard onto
the delivery end of the pump tubing 56. In order to do this,
dismantle the tubing guard and slide the union nut first, fol-
lowed by the thrust piece, onto the tubing.
Connect the tubing to the PEEK coupling and screw the union
nut onto the coupling to lock the tubing.
5 Fitting the filter unit
Using two 6.2744.010 PEEK pressure screws 54 and a sec-
tion of aspiratory tubing/capillary 26 (6.1803.0X0), screw the
optionally available 6.2821.120 PEEK filter unit 59 onto the
6.2744.160 PEEK coupling 58 at the outlet end of the pump
tubing 56.
Correctly set the contact pressure:
Push the contact pressure lever 49 up until the solutions are just being
aspirated. Then push the contact pressure lever one more detent posi-
tion up to achieve an optimum contact pressure.
The delivery rate of the peristaltic pump primarily depends on the in-
side diameter of the pump tubing 56, besides the correct contact pres-
sure. Different pump tubings are used depending on application.
The table on the following page provides information on the characteris-
tics and use of the available pump tubings.