Operating Principle - Thermo Scientific Dionex UltiMate 3000 Series Operating Instructions Manual

UltiMate 3000 Series:
NCS-3500RS and NCP-3200RS

8.2.3 Operating Principle

The loading pump is a zero-pulsation, serial dual-piston pump with electronic
compressibility compensation. The pump head includes two cylinders—working cylinder
and equilibration cylinder—that are connected in series. The solvent passes both cylinders
successively.
Continuous delivery is achieved as follows: The working cylinder delivers at the appropriate
flow rate while simultaneously filling the serially connected equilibration cylinder. The latter
serves as a reservoir and delivers while the working cylinder carries out the suction stroke.
The picture illustrates how the pump operates.
No. Element
1 3-channel proportioning valve
2 Pump head with
working cylinder (no. 2a) and equilibration cylinder (no. 2b)
3 Purge unit
4 Inline filter
5 Pump outlet
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Fig. 93: Operating principle of the loading pump
Operating Instructions