Waters 1500-Series, Operator'S Manual

Page: 112 / 188

5-4 Maintaining the HPLC Pump
Requirements:
• If your eluent is not miscible with methanol, use an intermediate
eluent.
• Move the eluent reservoir below the pump head level to prevent
gravity flow of the eluent.
3. For binary pumps, disconnect Pump B from the tee by removing the
outlet tube of the pulse dampener; install a compression plug in its
place.
4. Disconnect the left-hand pump head outlet tube from the draw-off valve
and install a compression plug in its place.
5. Place absorbent tissues under the disconnected pump head outlet tube
and the disconnected pulse dampener tube to catch drips.
6. Ensure that the draw-off valves are closed and the eluent directed to
waste by turning the reference valve 1/2-turn to the right (for 1525
μ
,
position the vent valve to vent).
7. Use the data control software to set the following pump parameter
values:
•
Flow rate:
For 1515 isocratic and 1525 binary pump – 0.3 mL/min
For 1525EF pump – 0.5 mL/min
For 1525µ pump – 0.2 mL/min
• High pressure limit:
For 1515 isocratic, 1525 binary pump and 1525µ pump – 41,370 kPa
(401 bar, 6000 psi)
For 1525EF pump – 34,475 kPa (334 bar, 5000 psi)
8. With the 100% methanol reservoir still connected to the pump inlet,
initiate the pump flow. Monitor pump pressure:
•
If the check valves are operating properly, pressure rises with each
plunger stroke on the connected head and then holds steady as the
plunger recedes.
• If there is a bad inlet check valve, pressure can possibly stop at a
certain point, or not rise at all.