Waters Prep Series Installation And Maintenance Manual page 133

• Pump head removal
• Pump seal replacement
• Pump plunger replacement
• Wash seal replacement
Pressure transducer calibration test
You must calibrate the pressure transducer to the system.
To perform a pressure transducer calibration test:
1. Disconnect the column from the flow path by turning the Purge valve on
the column rack to PUMP Purge.
2. To start the system, access the DIRECT CONTROL (PowerLine
controller) or ISOCRATIC (Gradient controller) screen.
3. Set the flow rate to 0.0 mL/min and observe the pressure reading on the
screen. It should be a positive value slightly greater than 0 psi.
The pressure value can read 0 psi even when the pressure
Tip:
transducer is not set properly, because the screen does not display
negative pressure.
Turn the screw slowly, because the screen's response to the
Tip:
adjustment lags. A transducer output that falls below 0 psi can cause
the screen to freeze. If the screen seems frozen, turn the potentiometer
to increase the pressure value above 0 psi. The ideal setting is 6 to 24
psi.
4. Adjust the pressure transducer.
A 2.5-second delay intervenes between the potentiometer
Tip:
adjustment and the on-screen pressure value.
a. Remove the left screw, below the transducer to reveal the coarse
adjustment.
b. Insert a jeweler's screwdriver into the center hole (fine adjustment),
Maintenance procedures 3-49