Pm-80 Pump Installation









Please retain the shipping box and packing materials until the unit has been fully tested. The shipping materials will be needed if you discover damage incurred during shipping.

The shipping box should contain the following items:

  • PM-80 Pump
  • PM-80 Accessories (includes: power cord, 1/8" PTFE inlet lines with fittings, 50 mL syringe).
  • PM-80 Manual
  • Optional Gradient Controller

If any discrepancies exist, retain the packing slip and contact BASi Customer Service for assistance.


The following two figures show front and back views of the PM-80 pump. The parts identified by number are described below.


1. Pressure display 18. Outlet check-valve assembly
2. Pressure transducer 19. Inlet tee
3. FLOWRATE control 20. Solvent-uptake line (Isocratic version)
4. POWER switch 21. Solvent-uptake frit (Isocratic version)
5. START/STOP switch 22. Outlet port to injection valve
6. FLOWRANGE switch 23. Connections to pulse damper
7. LOCAL/REMOTE switch 24. Optional connections to mixer
8. MINIMUM pressure (low limit) 25. Solvent intakes (gradient version)
9. Minimum pressure warning LED 26. Air filter
10. MAXIMUM pressure (high limit) 27. Offset adjustment for pressure output
11. Maximum pressure warning LED 28. Voltage selector
12. Prime/purge valve 29. Power input
13. Pump head 30. Fuse
14. Pump-head release lever 31. LCD Controller connector
15. Pump-head indicating LED 32. Terminal strip
16. Plunger-irrigation port (hidden) 33. REMOTE connector
17. Inlet check-valve assembly 34. BAS Instrument Control connectors






The PM-80 pump is designed to serve as the base for a stack of BASi chromatography instruments. A typical setup is illustrated by the BAS-480e chromatograph. The components of this system are (from the bottom up) the PM-80 pump, LC-22C temperature controller, and CC-5 flowcell compartment. The epsilon LC detector is on the left.

Location considerations for the pump must, of necessity, include the requirements for all the component instruments in the stack. Use the following guidelines:


  • Provide a surge-free power source which can be dedicated to the chromatograph. Other laboratory instruments such as ovens, vortex mixers, centrifuges, and large motors may cause spikes in the power supply.


  • Ensure that all components of the chromatograph share the same ground circuit. This can best be accomplished by plugging all components into a multi-outlet power strip. Plugging the components into independent outlets can produce ground loops (current that flows between ground circuits at slightly different potentials) which can produce baseline noise.


  • Locate the chromatograph on a stable bench. Vibrations can hamper the performance of any sensitive instrument.


  • Select a room where temperature remains stable throughout the day. Avoid installing the chromatograph near windows, air ducts, ovens, or refrigerators.


  • Place the chromatograph away from busy, congested areas. Remote, isolated areas are best for high-sensitivity work.


  • Avoid very dry areas and areas that are carpeted. Static electricity can affect instrument performance. Anti-static floor mats and bench mats are useful if spiking caused by static charge is a problem.


  • Avoid areas where radio-frequency interference is likely. Beeper-type paging devices can be a problem in some installations.







The power cord attaches to the PM-80 via the receptacle on the rear of the instrument. The pump can be operated with either 100, 120, 220, or 240 VAC and 50 or 60 Hz power, but the correct voltage must be selected before use at the cord connector:

Should the power option need to be changed, unplug the line cord and slide the plastic window to the left. The orientation of the small circuit board now exposed in this socket determines the voltage option. If the voltage labeled on the outer edge of this board is not that required, pull out the board and turn it such that the desired voltage is readable. Reinsert the board and push the fuse holder back into the cavity. Also check to see that the fuse is the proper rating:


Voltage Fuse
100-120V 3 A/SB
220-240V 1.5 A/SB






The PM-80 is factory plumbed, and ready as received for final connection of the inlet and outlet solvent lines. Unwrap the PTFE tubing carefully and remove the protective cover from the solvent-uptake frit. The uptake tubing connects to the tee at the pump head with a flangeless fitting. Be sure to install this with the flat face of the ferrule entering the tee:

Connect a solvent-outlet line between the prime/purge valve and the pump input of your injection valve. A nut and ferrule are provided for connection to the prime/purge valve. We recommend 1/16" OD, 0.015" ID, #316 stainless steel for this line. An in-line filter assembly (MR-4135) is recommended between this tubing and the injection valve.

Installation is now complete. Refer to the STARTUP section to begin purging the pump.






The gradient version of the PM-80 pump differs from the isocratic version in the number and location of solvent uptake lines, and in the presence of an internal high-pressure mixer.

Connect the three solvent-uptake lines to the ports marked 'A', 'B', and 'C' on the left side of the pump. Be sure to observe the correct orientation for the flangeless ferrules. The solvent-uptake frits should be placed into three bottles of freshly filtered mobile phase. (For initial startup, cleaning, etc., you may put all three uptake lines into the same bottle of 40:60 acetonitrile:water or other appropriate solution.) For best results, elevate the mobile-phase bottles to provide hydrostatic pressure to the pump.

WE STRONGLY RECOMMEND the use of the LC-26 DEGASSER. Use of an on-line degasser is required for dependable and continuous performance during gradient operation.

The HIGH-PRESSURE MIXER is located inside the cabinet, at the front, upper-right side. Four steel tubes emerge from the cabinet at this point: the two labeled 'M' come from the mixer, while the two unlabeled tubes come from the pulse damper. The two uses are mutually exclusive. Isocratic operation will benefit from a pulse damper, and does not require a mixer. Gradient operation does require a mixer, and will be impaired by the large dead volume of a pulse damper.

To convert from isocratic to gradient operation, remove the tubes from the pulse damper at the pressure transducer and the purge valve, and replace them with those from the mixer.


The mixer motor is software controlled: it turns on whenever a method calls for more than one bottle of mobile phase.






Communication with other instruments is accomplished via connections to the rear panel:

The only connection that needs to be made to an epsilon system is via the COMM NET port. Insert the female end of the 9-pin cable provided into either COMM NET port. The other end of this cable is connected to 'PUMP' connector on the rear panel of the epsilon controller. This connection needs to be made only if you wish to control the pump from the computer. Many users prefer to control the pump from its front panel (see the section on Manual Controls).

Additional connections are provided for other applications:


Pressure. Provides a 1 V per 1000 PSI output to monitor pressure. The output indicates absolute pressure when the offset adjustment is fully counter-clockwise.

To monitor pressure with an epsilon system, connect the 'PRESS.' terminal and its 'GND' as an external detector with a 10V input. Click here for details.

To monitor pump pressure with a chart recorder, first set your chart recorder for an input of 10 V. Connect two wires from the PRESS. and GND connectors on the terminal strip of the PM-80 to the input of the chart recorder. Adjust the PRESSURE OFFSET potentiometer on the rear panel of the PM-80 until the chart-recorder pen is about mid-scale. Now reduce the input voltage of the chart recorder in steps, adjusting the PRESSURE OFFSET control as necessary to keep the pen on the chart. Reduce the input voltage of the chart recorder until the pressure fluctuations can be measured on the chart (a 0.1 V input range should be about right). The analog pressure output produces 1 volt per 1000 PSI. The chart can be calibrated with the following formula:

READY. A switch closure or TTL-low across the READY and GND terminals will trigger the start of a timed run. Used to accept a 'ready-to-inject' signal from an autosampler (gradient versions).

INJECT. Sends a six second TTL-low signal at the start of a timed run. Used to trigger an autosampler to inject (gradient versions).

µBore. A switch closure or TTL-low across the µBORE and GND terminals will switch the pump from normal flow ranges (0-5 mL/min) to µbore ranges (0-0.5 mL/min). Used to slow down the flow rate after a series of runs, to conserve mobile phase. For example, a switch closure signal from an autosampler after the last sample has been injected will change a 1 mL/min flow rate to 100 µL/min. WARNING: running at low pressure might decrease plunger-seal life.

    • P = (1000 x D x V) / W


        P = pressure fluctuation in PSI

        W = width of chart paper (mm)

        D = magnitude of pen deflection (mm)

        V = input range of chart recorder (Volts)


REMOTE. This 25-pin 'D' connector is not currently used.

SYSTEM DIRECTOR. This 15-pin 'D' connector is provided for the LCD gradient controller or the DA-5/ChromGraph computer system.

PRESSURE OFFSET. This potentiometer is used to adjust pen position when recording pump pressure.