Waters 1500-Series, Operator'S Manual

Page: 92 / 188

4-8 Preparing for Operation
Operating with the plunger seal wash system
If your HPLC pump includes the plunger seal wash system, during operation,
plunger seal wash solvent flows from a reservoir to the solenoid wash pump,
which pumps the solvent through the fluid path.
• In the 1515 isocratic, 1525 binary, and 1525EF models, the solvent flows
through the pump head supports.
• In the 1525µ model, the solvent flows through the pump heads.
When the solvent has passed through all four pump heads or pump head
supports, it flows to waste. The plunger seal wash solvent is not recycled.
Powering-on the instrument triggers the seal wash pump’s priming sequence,
which lasts for one minute. The seal wash pump then shifts to its normal
operating mode, intermittently pumping seal wash solvent according to the
duty cycles in the following table.
Once you stop using the instrument, seal washing continues for 30 minutes
after the mobile phase stops flowing.
Tip:
The seal wash pump returns to the priming sequence each time the
instrument is powered-on. However, the seal wash pump requires priming
only for first-time use or when the line is dry (see page 4-9 ).
The following table shows the amount of seal wash solvent consumed during
normal operation.
Seal wash pump duty cycles
Mode Operation
Priming Solenoid energized for 0.5 seconds, solenoid off for 0.5
seconds, repeating.
Normal Solenoid energized for 0.25 seconds, solenoid off for 59.75
seconds, repeating.
Seal wash solvent consumption
Model Seal wash solvent consumption
1525 binary 12 mL/hr
1525µ 11 mL/hr
1525EF 13.5 mL/hr