Bissell HS-20 instruction manual Iii

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THE INSTALLATION, OPERATION, AND/OR SERVICING OR DIFFUSION PUMPS INVOLVES ONE OR MORE OF THE FOLLOWING HAZARDS, ANY ONE OF WHICH, IN THE ABSENCE OF SAFE OPERATING PRACTICES AND PRECAUTIONS, COULD POTENTIALLY RESULT IN DEATH OR SERIOUS HARM TO PERSONNEL.

Hazard

Suggested Corrective Action

Loss of utility: water and/or electricity

Provide sufficient backup water and power supply as neces-

 

sary to effect a safe shutdown under worst case conditions.

Overpressure in foreline

Provide an interlock to ensure that the power supply to the

 

pump heater cannot be activated if the foreline pump is not run-

 

ning AND/OR pressure in foreline is above 0.5 Torr (66.5 Pa).

Overtemperature

Insufficient water flow through the maincooling coils

Water trapped between inlet and outlet of quick-cool coil,or liquid nitrogen trapped between inlet and outlet of liquid nitrogen trap

Fit temperature sensors and pump fluid level sensors with feedback to an interlock on the heater power supply.

Use water flow sensor and feedback to interlock the heater power supply.

Provide vent or pressure relief valves for both quick-cool coil and liquid nitrogen trap.

Loss of ground integrity

Incorporate ground fault interrupt circuit into heater power

 

supply.

Positive pressure in pumping system

Integrate pressure relief valve in vacuum system.

High voltage

Prevent personnel contact with high voltages; design and

 

attach warnings.

Toxicity/Corrosivity

Toxic and/or corrosive gases must be vented to a safe loca-

 

tion, ensuring adequate dilution or scrubbing to safe levels,

 

taking all action required to meet air quality standards.

Explosion

Integrate pressure relief valves in all systems using pumps

 

10 inches or larger in diameter.

 

Do not use or recommend the use of hydrocarbon-based

 

pumping oils.

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Contents HS-20 Diffusion Pump Sales and Service Offices Telephone Numbers Warranty Replacement and Adjustment WarrantyPage Page Iii Prohibited Action Explosion-Causing Condition Prohibited Action Result Page Vii Page Page Section Safety Considerations Section I Installation Table of ContentsList of Tables List of IllustrationsOperating Specifications See Figure Installation GeneralModel Technical Specifications ASA Outline Drawing HS-20 Diffusion Pump, with ASA Flanges Unpacking Cleaning a NEW PumpInstallation Cooling Water Connections See Figure Safety Considerations and InterlocksUtility and System Connections Vacuum ConnectionsCooling Water Connections Initial Vacuum Test Thermal Switches240/400/430/440/480 V Wiring Diagram HS-20 Diffusion Pump 415 V Wiring Diagram HS-20 Diffusion Pump Adding Pump Fluid Sight Glass Assembly Operation START-UP ProcedureOperation Shutdown ProcedurePeriodic Inspection Maintenance GeneralCleaning MaintenanceDo not overtighten the screw Disassembling and Reassembling the Cold CAP Refer to FigureExternal Fittings Cold Cap Assembly Disassembling the Jet Assembly Refer to Figure JET AssemblyDisassembling the Lower Jet Assembly Inch Jet Assembly Reassembling the Jet Assembly Maintenance Reassembling the Lower Jet AssemblyHeater Replacement Jet Coupling Tighten clamping nuts to 250 in.-lbs Maintenance Replaceable Parts Maintenance Outgassing Troubleshooting LeakagePoor Pump or System Performance Troubleshooting