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Chapter 1 Introduction and hardware
Page 1-12 MAN 0318
Adjusting the tubing length
Depending upon the titration sample volume used and the type of titration
being performed, the length of the tubes can be altered to be either higher or
lower within the sample container. This is done as follows:

Loosen the clamping screw , to loosen the tubing clamping ring .

Carefully pull the tubing either up or down to the required height.

Tighten the clamping screw to secure the tubing to be clamped in posi-
tion.
Note
The clamping ring can be used for securing both thin and thick tubing
diameters in place. Thick tubing (1/8”) is supplied as standard for connect-
ing the sample flow in and out of the sample container.

Titrant tubes
The titrant tubes are fed directly from the manifold to the sample container.

Sample in connector (from Zetasizer)
The sample that has been measured is re-circulated to the sample container via this
connector.

Sample out connector (to Zetasizer)
The sample to be measured is recirculated through this connector to the cell in the
optical unit. For biological samples, a syringe filter of minimum size 0.22
μ m can be
placed on the exit of this connection to filter oversized particles. This filter should
be replaced regularly to maintain optimum filtration.

Sample to pump
This connection feeds the sample from the sample container to the pump before
passing to the sample out connector.

Purge connector
Warning!
If a Nitrogen supply is used the system must be located in a well ventilated
environment. Turn
off the supply when not in use.
See Appendix B for a requirement specification for the Nitrogen supply.
The purge connection is provided to enable connection of a Nitrogen purge sup-
ply. This is used to prevent any absorption of oxygen that may change the pH char-
acteristics of the sample, i.e. cause a pH drift. Though the amount of pH drift is
dependent upon the alkalinity of the sample, even for a sample with a low alkalinity
this drift will be noticeable. The need to eliminate this drift is therefore of particu-
MAN0318-4.0 - MPT-2 Autotitrator-Degasser.book Page 12 Tuesday, September 4, 2012 12:15 PM