The EcoSEC GPC system contains two independently operating temperature controlled pumps (pump oven). The main pump delivers solvent to the column. An identical secondary pump delivers the same solvent via a 'reference column' to the reference cell of the refractive index detector. The primary benefit derived from the second pump is an improvement of RI baseline stability. Controlling the temperature of the pump housing and tubing further improves baseline stability by removing the effect of temperature fluctuations on solvent delivery. As an added benefit, the secondary pump may also be used in a column switching mode (optional) to allow for a quick change-over from, for instance, a high MW column to a low MW column. All components shown in the picture can be maintained at a constant temperature within the range of ambient plus 10°C to 50°C upon closing the cover door (left). The following performance data apply to each pumping unit:
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Short start up and set up time |
| High reproducibility |
| Liquid supply mode: |
Parallel flow (Quick return) |
| Flow rate setting range: |
10 to 2,000 μL/min (1 μL steps)
(Sample flow rate only. The reference flow rate is set according to the ratio [1, 1/2, 1/3, or 1/4] to the sample flow rate.) |
| Flow rate accuracy: |
Within ±2 % or ±5 μL, whichever is greater (H2O liquid supply pressure: 1 MPa or more and 1,200 μL/min or lower) |
| Flow rate precision: |
Within ±0.2 % or ±1 μL, whichever is greater (H2O liquid supply pressure: 1 MPa or more and 1,200 μL/min or lower) |
| Pressure setting range: |
0 to 25 MPa (0.1 MPa steps) |
| Plunger diameter: |
φ2 mm |
| Plunger volume: |
7.5 μL/stroke |
| Accumulator contents: |
3 mL |
| Safety mechanism: |
Flow stop above the upper-limit pressure
Flow stop below the lower-limit pressure
Plunger drive count monitoring
Pan for liquid leakage |
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