BUCHI PrepChrom C-700 - Manual (Page 24)

4 | Description of function BÜCHI Labortechnik AG
24/110 PrepChrom C­700
4.3.3 Control unit
The system is controlled by the central processing unit via a 10.1" touch screen,
the keyboard and mouse can be used optionally. The operator uses the control
software to run the device.
The control unit centralizes the connection for data to the other modules.
4 USB connectors are available, 1 in the rear and 3 on the right side of the
touch screen (cable maximum length = 2 m).
4.3.4 Pump
Fig. 7: Pump module components
1 Check valve 2 Pump head
3 From the 4­way aspiration valve 4 Leak sensor
5 Chamber, pressure sensor 6 To the mixing chamber
The 2­head pump delivers mobile phase at flow rates between 5–250 mL/min
with low residual pulsation. It is a high performance double­piston pump (recip­
rocal movement). A system (pulleys + belt), a stepper motor drives 2 cams on
which lean the 2 pistons. Their motion generates a cycle and then creates the
aspiration.
A static mixing chamber at the outlet ensures a suitable mixing of solvents
whatever the working flow rate is.
A sensor detects leakages. The pump is interrupted if a leakage occurs and the
user is informed via the touch screen.
A pressure sensor monitors the current pressure. If the pressure is higher than
100 bar the pump will be switched off to prevent any damage to the system.
NOTE
When working with aqueous solutions, residues might collect behind the piston
seals. These residues must be removed since they can contribute to a faster
wearing of the seals. Rinsing of the piston cleaning disc is described in 7.2.4
Piston cleaning disc, cleaning [
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