WPI PicoPump PV830, Инструкция по эксплуатации

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PV830 Pneumatic PicoPump
World Precision Instruments 3
INSTRUMENT DESCRIPTION
NO NC
Pressure Input
Filter
Pressure
Regulator
Pressure
Gauge
Pressure Gauge
Pressure
Regulator
Solenoid
Toggle Valve
(vac/hold)
Pressure Output
Vacuum Gauge
Vacuum
Regulator Filter
Vacuum Input
Filter
Inactive
Active
Hold
Vacuum
Toggle Valve
(Vac/Atm)
Atmosphere
Vacuum/Atm
Output
Fig. 2—The pnematic block diagram of the PicoPump is shown.
Both pressure lines ( Hold and Eject ) and the vacuum line pass through precision
regulators and are monitored by measuring gauges (Fig. 2). A fast solenoid
valve controls the application of the
Eject
pressure to the
Pressure Port
. When
the solenoid is inactive, the Pressure Port is connected to the Hold pressure.
Alternatively, the solenoid can be vented to the vacuum/atmosphere line, depending
upon the position of the Vac/Hold toggle switch. This feature allows the pressure
ejection channel to have a mild sucking action when pressure is not being applied.
A manual pneumatic switch also allows the vacuum/atmosphere line to be used
independently of the solenoid-controlled Pressure line.
Quantitative control over the amount of fluid injected is attained by adjusting the
pressure and the duration of the pressure pulse. For dispensing aliquots of as little
as tens of picoliters through micron-sized pipette tips, pressures of 10 to 100PSI are
used in pulses as brief as 10ms. Longer pulses, higher pressures and larger pipette
tip diameters give correspondingly greater amounts of fluid. For convenience, the
pressure is usually kept constant throughout a series of experiments and the pulse
width is varied to give different amounts of injected fluid.
The Startup Kit (WPI #
3316
) includes:
(1) 0.25” NPT Fitting for nitrogen tank regulators
(2) 0.25” quick connect fit barbs (use on vacuum side, where applicable)
(1) 5’ hard tubing