This manual explains the installation and operation of the PM-92 dual-head and PM-91 single-head Pump, as well as procedures for routine maintenance and troubleshooting. Read the entire manual prior to installation and start-up.

NOTE: We will refer to the pump as the PM-90 when when the information refers to both models.

The PM-92 is a reciprocating, dual-piston unit. It is designed for precise and reliable solvent delivery for isocratic elution at flow rates between 1.0 and 2000 µL/min. Advanced features of the PM-92 pump include:

• Dual independently controlled reciprocating pistons each driven by a microstepping motor through a high efficiency ballscrew.
• Solid-state pressure transducers monitor each piston's head pressure along with system pressure to provide smooth crossover from one piston delivery to the next.
• Minimal flow-through volume. No pulse damper required for all but the most demanding applications.
• Optimized for microbore flow rates.
• Piston velocity profile and stroke length is software controlled.
• Pump performance is independent of system backpressure.
• Each head is removable as a single, precision-engineered assembly which may be interchanged in seconds.
• High- and low-pressure limit controls, for safety.
• Analog output for pressure monitoring.
• Provision for remote-control operation.
• Wetted materials: 316 stainless steel, sapphire, UHMW polyethylene, Teflon, PEEK.

The PM-91 is a reciprocating, single-piston unit. It is designed as an economical alternative to the PM-92 for isocratic elution at flow rates between 1.0 and 1200 µL/min. Advanced features of the PM-91 pump include:

• Reciprocating piston driven by a microstepping motor through a high efficiency ballscrew.
• Solid-state pressure transducer monitors head pressure and system pressure independently.
• Microprocessor control takes a 'snapshot' of system pressure just prior to refilling and drives the plunger to quickly refill and pressurize the mobile phase to the 'snapshot' pressure before resuming the desired delivery flow rate.
• Fast refill and pressurization in combination with a pulse damper provides minimal flow and pressure fluctuation.
• Optimized for microbore flow rates.
• Pump performance is independent of system backpressure.
• The pump head is removable as a single, precision-engineered assembly which may be interchanged in seconds.
• High- and low-pressure limit controls, for safety.
• Analog output for pressure monitoring.
• Provision for remote-control operation.
• Wetted materials: 316 stainless steel, sapphire, UHMW polyethylene, Teflon, PEEK.

The PM-90 series pumps have been engineered for durability, and with proper maintenance should provide years of reliable service.

HEIGHT	4.6 inches
LENGTH	9 inches
WIDTH	11 inches
WEIGHT	15 pounds
FLOW RATE	1-2000 (PM-92) or 1-1200 (PM-91) µl/min
FLOW PRECISION	better than 0.3% RSD
FLOW REPEATABILITY	0.3%
PRESSURE RANGE	0-5000 PSI (0-34 bar) with selectable limits
INPUT VOLTAGE	100/120/220/240 vac 50/60 Hz
POWER	2A (max) @ 120 VAC 50/60 Hz

• PM-90 CONTENTS
• EPSILON CONTENTS