www.restek.com
7
3.1.1
Prime/Purge Valve
CAUTION:
When you press the PRIME key, the pump will run at the maximum flow rate. Be sure the prime/purge valve is open.
The prime/purge valve vents the flow to atmosphere and permits efficient priming of the dual head pump. When the valve is
closed firmly fully clock-wise, high-pressure flow is directed to the Filter/Outlet port. When the valve is opened one-half to one
full turn counter clock-wise, pressure is vented and flow exits through the drain port in the prime/purge valve stem assembly.
Suction with a Luer tip syringe at the drain port will purge air bubbles from the pump and reservoir lines (provided there are no
open valves to lines down stream at the injector/column interface). To prime the pump, draw about 20 to 30 mL of mobile phase.
3.1.2
Filter/Outlet
A high-pressure in-line filter (0.5 micron rating) is included at the output of the dual head pump. The Filter/Outlet port is the
high-pressure filter closure and is designed for a
1
/
16
" OD tubing connection.
3.1.3
Control Panel
Special note concerning flow rate limit:
This pump is designed to operate in constant pressure mode (flow rate auto-adjusts to maintain desired pressure). The user may
also lower the maximum flow rate of the pump (12 or 24 mL/min. maximum, depending on model), particularly if pressure is
overshooting while packing small bore columns.
When in Flow MODE (mL/min. LED continuously lit ), the user may lower the maximum flow rate, using the UP & DOWN
arrows as described below. This may be performed before the beginning of a run or during a run. Note that when in maximum
flow mode (mL/min. indicator on constant), the digital display shows only the upper flow rate limit, not the actual flow rate. The
actual flow rate is displayed, using the MODE key, when the mL/min. indicator is blinking.
3.1.3.1 Digital Display
The 4-digit display shows the pump’s maximum flow rate (mL/min.), pressure setting (psi), the set upper or lower pressure limit
(psi), the actual pressure (psi), or actual flow rate (mL/min.) when operating. Choice of display is selected with the MODE button.
Pressure is set from the Pressure Mode Only (steady psi light).
3.1.3.2 Keypad
When pressed, this button alternately starts and stops the pump.
When pressed, this button increases the pressure in pressure mode or the maximum flow rate in flow mode.
When pressed, this button decreases the pressure in pressure mode or the maximum flow rate in flow mode.
When the PRIME button is pressed, the pump runs at the maximum flow rate. It will stop when any button is pressed.
MODE
Use this button to cycle through five display modes: maximum flow rate, pressure setting, upper pressure limit, lower
pressure limit or actual pressure. A status LED to the right of the digital display indicates which mode is active. A
steady psi light indicates set pressure, a flashing psi light indicates actual pressure.
A steady mL/min. light indicates
maximum set flow rate, a flashing mL/min. light indicates actual flow rate.
Fast And Slow Button Repeat On The Up And Down Arrow Buttons: If the UP-ARROW or DOWN-ARROW button is held
down for more than approximately one half second, the button press will repeat at a slow rate of approximately 10 times a second.
Once slow button repeat has begun, fast button repeat can be initiated by using a second finger to press down the second arrow
button. During fast button repeat, the button press will repeat at a rate of approximately 100 times a second. Switching back and
forth between repeat speeds can be accomplished by pressing and releasing the second arrow button while holding the first arrow
button down.
