Pressure Swing Dryers (PSD2 & PSD4)

Pressure Swing dryers provide a source of very dry compressed air for use as a zero gas in humidity calibration systems, or for general laboratory applications.

The Michell PSD Series Pressure Swing Dryers use two columns filled with 4Å molecular sieve desiccant, which are used alternately on a two-minute switching cycle. The PSD dryers are designed to operate continuously, using a small proportion of the dried air, to regenerate the offline column - generally giving desiccant life in excess of five years. This type of heatless regeneration also uses significantly less energy than a 'heated' type of dryer.

Product Features

  • Excellent long term stability
  • Maintenance free except for a desiccant change once every 5 years
  • Completely self-contained
  • Low power consumption
Pressure Swing Dryers

Technical Specifications

Model PSD2 PSD4
(High flow volume)
(High pressure output)
Gas output
Flow 7 Nl/min (14.8 scfh) 30 Nl/min (63.6 scfh) 90 Nl/min (109.7 scfh) 30 Nl/min (63.6 scfh)
Pressure 0.5 barg (7 psig) User-settable up 8 barg
(116 psig)
Moisture content<1ppmv<13.8ppbv
Input Requirements
Gas supply
Flow 10 Nl/min (21.2 scfh) 30 Nl/min (63.6 scfh) 90 Nl/min (109.7 scfh)30 Nl/min (63.6 scfh)
Pressure5 to 7 barg (70 to 100 psig)6 to 10 barg (87 to 145 psig)
Moisture content Oil and liquid water-free<16ppmv
Electrical Input
Power100 to 115 OR 220 to 240 VAC, 50/60Hz100 to 240VAC 50/60Hz
Power connectionIEC socket
Environmental Conditions
Operating temperature+5 to +35°C (+41 to +95°F)+10 to +40°C (+50 to +104°F)
Storage temperature -40 to +35°C (-40 to +95°F) -40 to +50°C (-40 to +122°F)
Mechanical Specifications
TypeTwin column desiccant, pressure swing
Desiccant4 Ångström Molecular sieve bead (4-8 mesh)
Amount required (approx.)2 Kg3.5 Kg
TimerMechanical camProgrammable relay
Gas connections
InletSwagelog ® ¼"¼" VCR Swagelok®
OutletSwagelog ® ¼"¼" VCR Swagelok®½" VCR Swagelok®¼" VCR Swagelok®
OutletNone Millipore Wafergard IIF Micro Inline (sealed type) with PTFE membrane element rated at >99.999% retention of 0.003μm particles
VentNone Bonded glass microfiber rated at >99.999% retention of 0.1μm particles
ConstructionRack mount: 19" x 6U x 324mm (12.8") 304 stainless steel wall mounting enclosure: 800x600x300mm (31.5x24x12”)
Weight12.5kg (27.5lbs)30Kg (66lb)35Kg (77lb)32Kg (70lb)


Metrology Research & Development

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