Automated Gas Handling System for Cryogen Free Dilution Refrigerators

Dec. 29, 2009 - PRLog -- Janis Research is pleased to announce its second generation Gas Handling System (GHS2) intended for use with the JDry series cryogen free dilution refrigerators.  The GHS2 contains Janis Automated Control Box (JACoB), Janis Mixture Enclosure (JAMiE) and Roots Pumping Station (RPS).  

The JACoB provides automated dilution refrigerator (DR) control based on a standard 19” enclosure, and incorporates a manifold of Pfeiffer miniature solenoid valves, three Pfeiffer wide range pressure sensors, MKS flow meter and control electronic. A powerful UPS unit allows more than one hour of battery-backed operation with all the electronics energized, including two computers and all valves.

The valve control electronics, pressure and flow sensor display, and pump control are based on rugged National Instruments cRIO platform. The real time operating system cRIO controller and I/O modules are housed inside a 4 slot cRIO chassis within the control box. Three cRIO plug-in modules control the valves, pumps and compressor, and also monitor the various sensors. A NI touch-panel computer (PPC2115 with Windows XP) is located on the front panel of the JACoB. The touch panel (TP) contains a mixture flow diagram with all valves, pumps, pulse tube (PT) compressor and gauges clearly displayed. The valves are opened or closed and pumps and compressor operated by depressing valve indicators (fields) on the flow diagram. The TP also serves as a gauge indicator, showing pressure and flow in real time. The TP communicates with the cRIO controller via internal LAN (Ethernet). The TP can be optionally placed in a remote location (control room) or a TP client program can be operated from any other Windows computer and connected to JACoB via built-in Ethernet port. All JACoB programming is done in Labview, including cRIO and touch-panel, but there is no need for a separate Labview license – all programs are installed as WindowsTM executables.

An independent Labview executable program is installed on the touch-panel computer and operates the DR temperature measurement and control system via GPIB interface. This program utilizes a LSCI model 370 temperature controller for resistive temperature sensors, and optional Agilent 4263B LCR meter for measuring CMN/FPD temperature measurement devices. This software plots and logs all temperature, pressure and flow data from JACoB in real time. It also performs PID control over the DR still and mixing chamber heaters.

JAMiE is based on a similar 19” enclosure with locking wheels, and contains two aluminum mixture dumps inside. Optionally, the JAMiE enclosure can be located under JACoB acting as its base. Two stainless steel flex-hoses connect JACoB and JAMiE. The system is charged with optimized 3He-4He mixture prior to system test; the precise mixture amount is specific for each particular DR model.

The RPS system contains an Alcatel oil-free 6-stage A100L Main pump, combined with RSV601 Booster pump, both using Roots technology. It does not require any mist filters; a single LN2 trap is supplied with JACoB as standard equipment.


For information: http://www.janis.com/AutomatedGasHandlingSystem.aspx or
Contact: Zuyu Zhao, Ph.D. at zzhao@janis.com
Phone: +1 978-657-8750, press 8 then 121.

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Janis Research is a manufacturer of cryogenic research equipment. Products include continuous flow and Helium-3 cryostats, 4 K and 10 K cryocoolers, dilution refrigerators, superconducting magnet systems, and micromanipulated probe stations.