SSI America 90-2581 REV B manual Microprocessor Control, DC Power Supply, Remote Interfacing

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4.2Electronic Control

4.2.1 Microprocessor Control

The pump is controlled by hybrid microprocessor circuitry which

(1)provides control signals to the motor drive circuitry, (2) interfaces with the keyboard/display, (3) receives signals from the refill flag, and

(4)provides external input/output (RS-232) interfacing. Firmware programming is stored in an EPROM.

An eccentric cam provides refill in a fraction of the full cam cycle. The remaining revolution of the cam provides piston displacement for outward flow of the mobile phase. In addition to the rapid refill characteristics of the drive, the onset of refill is detected by an infrared optical sensor. The microprocessor changes the refill speed of the motor to an optimum for the set flow rate. At 1ml/min, the refill rate is more than five times faster than if the motor operated at constant speed. The optimum refill rate minimizes the resulting pulsation while avoiding cavitation in the pump head.

The flow rate of any high pressure pump can vary depending on the operating pressure and the compressibility of the fluid being pumped. The Binary Solvent Delivery Module is calibrated at 1000 psi using an 80:20 mixture of water and isopropanol.

4.2.2 DC Power Supply

Power for the pump is provided by a switching power supply which accepts voltages from 90 – 240 VAC. Output is 24 VDC for the pumps and heater. A switching 5 VDC supply is also provided to power control and display circuits.

4.2.3 Remote Interfacing

RS-232C modular jacks are provided on the back panel. See

Appendix A for information on operation via this connection.

4.2.4 Motor Stall Detector

The motor can stall and create a loud buzzing sound if the flow path connected to the pump's outlet becomes plugged, if the pressure exceeds the maximum pressure rating of the pump, or if the mechanism jams. If a motor stall occurs, the electrical current being supplied to the motor is turned off and the fault light is turned on.

The Motor Stall Detector is enabled or disabled during power-up by pressing and holding the RUN/STOP and the PRIME buttons while the power is switched on. Release the buttons when the display displays "SFE". To enable the Motor Stall Detector press the UP- ARROW button and the display will display "On". To disable the

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Contents Binary Solvent Delivery Module Operators ManualPage 1.INTRODUCTION 1.1.1 Pump Features fFast & easy setup1.1.2 Wetted Pump Materials 1.1.3 Self-FlushingPump HeadMicroprocessor advanced control 1.1.4 Self-Flushand Seal Life It is recommended that the Self Flush feature be used to improve seal life in a number of applications. In particular, as stated above if pumping Buffers, Acids/Bases or any inorganic solution near saturation, the pump should utilize the Self Flush feature. With every piston stroke, an extremely thin film of solution is pulled back past the seal. If this zone is dry without use of Self Flush, then crystals will form with continuous operation, which will ultimately damage the sealFlow Rates 2.2Location/Environment 2.INSTALLATION2.1Unpacking and Inspection 2.3Fluid Connections & PrimingConnect wash solution inlet and outlet tubing SELF-FLUSHPUMP opaque to the flush housing as shown2.5.1 Solvent Out-gassingand Sparging 2.4Electrical Connection2.5Solvent Preparation 2.5.3 Filtration 2.6.1Mobile Phase Reservoirs2.5.2 Cavitation 2.5.4 Initial system pressurization Daily2.6.4 Priming the Pump and the Flushing Lines 2.6.2 Self-FlushSolution2.6.3 Inlet Tubing and Filters 2.6.6 Long Term Pressure Calibration Accuracy2.7.1Isopropanol Flush 2.7.2 Packaging for Shipping2.7Preparation for Storage or Shipping 3.OPERATION 3.1.1Control PanelNon-volatileMemory Reset If the pump is operating erratically, there is the possibility that the memory has been corrupted. To reset the memory and restore the pump to its default parameters, press and hold the UP-ARROWbutton when the power is switched on. Release the button when the display reads rES. The parameters stored in non-volatilememory, i.e., the flowrate, the pressure compensation, the voltage/frequency select, the lower pressure limit, and the upper pressure limit will be set to the factory default values. The head type setting is the only parameter not changed by the non-volatilememory reset function. If the firmware is upgraded to a newer version, a non- volatile memory reset will automatically occur the first time the power is switched on 3.6Symbols 3.5Rear Panel Remote Input4.1.2 Pump Cycle 4.THEORY OF OPERATION4.1.1Liquid System Flow Path 4.1.3 Pulse Damping4.2.3 Remote Interfacing 4.2.2 DC Power Supply4.2.1 Microprocessor Control 4.2.4 Motor Stall DetectorPage 5.2.1Removing a Pump Head 5.MAINTENANCE5.1.1 Inlet Filters 5.1Filter Replacement3.Remove the inlet line from the inlet check valve OUTLET FLUSHING CHECK VALVE OUTLET FLUSHING 5.2.2 Cleaning the Pump Head Assembly 1.Inspect the piston seal cavity in the pump head. Remove any foreign material using a cotton swab, or equivalent, and avoid scratching the sealing surfaces. Repeat for the self-flushhousing. Be sure no fibers from the cleaning swab remain in the components3.If the check valves have been removed, tighten the check valves on stainless steel pumps to 75 inch-poundsor enough to seal at maximum pressure. Do not exceed maximum torque. For Bioclean PEEK pumps, tighten each check valve firmly by hand. Do not go ¼ turn past finger tight 5.2.3 Replacing Piston Seals Lower than normal pressure, pressure variations, and leaks in the pumping system can all indicate possible problems with the piston seal. Depending on the fluid or mobile phase used, piston seal replacement is often necessary after 1000 hours of running time1.Remove the pump head as described in Section 5.2.1. Use caution so as not to damage the sapphire piston 5.2.4 Changing the Piston 5.Condition the new seal as described in Section5.2.5Replacing the Pump Head 5.3Conditioning New Seals5.4Check Valve Cleaning and Replacement 5.5.1Removing the Pulse Damper5.5.2 Pulse Damper Refurbishing 5.5Pulse Damper Replacement5.5.3 Pulse Damper Installation 5.6Cleaning the Pump5.8Other Pump Maintenance 5.7Lubrication7-14 5.9Fuse Replacement 1.Unplug the unit 2.Remove the cover You Notice 6.PROBLEM SOLVINGQuick Guide to Problem Solving This May Mean7.LIST OF REPLACEMENT PARTS 880201 Seal Kit, Aqueous, 5mL Part Description APPENDIX AA.1.1 Hardware Implementation Part NumberCommand Interpreter A.1.3“/” character Page A.2.1 Pressure Fault and Motor Stall Fault Output A4-pinterminal board connector and a 10-pinterminal board connector are provided on the back panel. Any device capable of providing the proper run/stop logic level, flowrate control frequency, or flowrate control voltage can be used as a remote controlling device for pump operation via this connection. The terminal board connectors can be removed for ease of connecting wires, if desired, by pulling firmly rearward and should be reinserted firmly afterwardA.2.2 General Information on Inputs the EVENT 1 terminal and the EVENT 2 and EVENT 3 terminals is affected. EVENT 2 is Normally Closed connected to EVENT 1 until a fault occurs and then opens. EVENT 3 is Normally Open not connected to EVENT 1 until a fault occurs and then closesA.2.4 Run and Stop Inputs The PUMP-RUN, PUMP-STOP,and ENABLE IN inputs operate from an internal 5 VDC source and each one draws approximately 0.008 amps when connected to COM. To activate either the PUMP- RUN, PUMP-STOP,or ENABLE IN input connect it to COM. Any device capable of switching 0.008 amps can be connected between the PUMP-RUN, PUMP-STOP,or ENABLE IN input and COM, such as: a switch contact, a relay contact, an open collector output, an open drain output, or any output with a high logic level output of 3.8 to 6.0 volts and a low logic level output of 0.0 to 0.5 volts. A switch contact or a relay contact is preferred since this type of connection will provide isolation between the pump and the controlling device. The COM terminal is internally connected to the pumps chassis ground and should be connected to the controlling devices ground or zero volt terminal when the controlling device has an open collector output, an open drain output, or any output with logic level outputA.2.4 Enable Input When activated ENABLE IN is at a low logic level, the ENABLE IN input disables flowrate control on the front panel and enables flowrate control on the back panelAPPENDIX B EZ GRIP FITTING GUIDEScientific Systems Inc Warranty Statement A-10