Related Manuals for MKS Granville-Phillips 274 Series
Summary of Contents for MKS Granville-Phillips 274 Series
- Page 1 Series 274 ® Granville-Phillips Series 274 Bayard-Alpert Type Ionization Gauges Instruction Manual Instruction Manual part number 274026 Revision B - August 2014...
- Page 2 Series 274 Tubulated and Nude Bayard-Alpert type Ionization Gauges. See Figure 2-1 on page 13, Theory of Operation on page 15, and Table 4-4 on page 28.
- Page 3 Andover, MA 01810 USA Phone: 1-978-645-5500 www.mksinst.com Instruction Manual © 2014 MKS Instruments, Inc. All rights reserved. ® Granville-Phillips is a registered trademark of MKS Instruments, Inc. All other trademarks and registered trademarks are the properties of their respective owners.
- Page 4 Catalog numbers for Granville-Phillips Tubulated (Glass) and Nude Ionization Gauges Detailed information regarding the catalog numbers listed below is provided in Figure 2-1 on page 13 and Table 4-4 on page 28.
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Page 5: Table Of Contents
Table of Contents Chapter 1 Introduction/Safety ........Definitions of Terms . - Page 6 Ionization Gauge Instruction Manual - 274026 - Rev. B...
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Page 7: Chapter 1 Introduction/Safety
Chapter 1 Introduction/Safety For personal and equipment safety, all safety notices, cautions, and warnings must the adhered to at all times when working on or around a vacuum system, whether or not the system is in actual use. Follow all safety instructions provided throughout this instruction manual, and all safety practices recommended by your company. -
Page 8: Electrical Shock
Chapter 1 CAUTION Caution statements alert you to hazards or unsafe practices that could result in minor personal injury or property damage. Each caution statement explains what you must do to prevent or avoid the potential result of the specified hazard or unsafe practice. -
Page 9: Explosion / Implosion
Introduction/Safety Explosion / Implosion WARNING Do not operate ion gauges in an explosive atmosphere or in the presence of flammable gases or fumes. Danger of explosion or inadvertent venting to atmosphere exists on all vacuum systems which incorporate gas sources or involve processes capable of pressurizing the system above safe limits. -
Page 10: System Grounding
Service Guidelines For customer service: If the product requires service, contact the MKS, Granville-Phillips Division Customer Service Department at +1-800-227-8766 or +1-303-652-4691 for troubleshooting help over the phone. For Customer Service or Technical Support 24 hours per day, 7 days per... -
Page 11: Chapter 2 Installation
Chapter 2 Installation Before installing a Series 274 Bayard-Alpert (B-A) gauge on your vacuum system, be sure you understand and follow the Cautions, Warnings, and guidelines presented in the Introduction/Safety Chapter of this Instruction Manual. If you are replacing an existing gauge, Figure 2-1 lists B-A style gauges that are equivalent to the Series 274 B-A gauges. -
Page 12: Electrical Connections
Electrical Connections Do not use gauge cables with exposed conductors such as alligator clips. All gauge pins must be covered by connectors or by pin covers (insulation). Gauge cables should be firmly clamped to the vacuum station to provide strain relief and ensure that minimal strain is transmitted to the gauge pins if there is motion between the gauge and the gauge controller. - Page 13 Installation Figure 2-1 Bayard-Alpert Ion Gauge Equivalent List * Notes: * Granville-Phillips Series 274 Nude Gauges are electrically equivalent to other manufacturers, but the pin geometry may be different. * Granville-Phillips Nude Gauges, catalog numbers 274022, 274023, 274028, and 274050 do not have a strain relief for the electrical connector.
- Page 14 Chapter 2 Figure 2-2 Series 274 Bayard-Alpert Ion Gauge Connectors Ionization Gauge Instruction Manual - 274026 - Rev. B...
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Page 15: Chapter 3 Operation
Chapter 3 Operation This chapter explains the basic operating principles of a Bayard-Alpert (B-A) ionization gauge, including: • Theory of operation of B-A gauges • Filament emission of B-A gauges • Pumping capacity of B-A gauges • X-ray limit of B-A gauges •... - Page 16 Chapter 3 Figure 3-1 Elements of a Bayard-Alpert Ionization Gauge Electrons are created by a hot filament and accelerated to the grid. The current is actively controlled by the electronics. The recommended operating voltage potentials are: Collector = 0 V; Grid = +180 Vdc; Filament = +30 Vdc See the Operating Characteristics Charts for variations of these parameters.
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Page 17: Filament Emission
Operation Filament Emission There are two types of materials commonly used for filaments: tungsten or thoria-coated iridium. The most common style is coated iridium because they operate at a lower temperature than tungsten, therefore less reactive. Coated iridium filaments are also more burnout resistant when exposed to atmospheric pressure while power is on. -
Page 18: X-Ray Limit
Chapter 3 Several gauge configurations are available to cope with the pumping phenomenon. The tubulated glass gauge equipped with a 3/4-inch tubulation, such as the 274002, has adequate conductance for use down to the 10 Torr scale. A gauge for use down to the 10 Torr scale is available with 1-inch tubulation (274015). -
Page 19: Degas Procedure
Operation may be obtained in a gauge when all the output current is due to X-ray induced photo emission and there is an absence of gas. The X-ray limit of standard glass or nude B-A gauges is approximately 3x10 Torr. To measure below this limit, an ultrahigh vacuum (UHV) nude B-A gauge can be used. -
Page 20: Bakeout Procedure
Chapter 3 preferable at ultra-high vacuum. • I R degassing is accomplished by passing current through the grid (anode) at a sufficient level to raise the grid temperature to displace the molecules. I R degassing requires longer degassing periods, and is preferable to perform only at pressures below 10 Torr. -
Page 21: Chapter 4 Technical Information
Chapter 4 Technical Information Operating Principle The pressure indication of a hot cathode Bayard-Alpert (B-A) gauge is based on the ionization of gas molecules by a constant flow of electrons. The negative electrons are emitted at a well-controlled, selectable rate from a heated cathode and are accelerated toward a positively charged wire grid (anode). -
Page 22: Specifications
Specifications Gas Species Effects Bayard-Alpert (B-A) ionization gauges have different relative sensitivities for different gas species. As a result, the pressure readout provides a direct reading only for the gas for which the gauge is specified (usually nitrogen). This is called a readout of nitrogen equivalent pressure. A simple mathematical conversion of the direct pressure readout to the pressure of the non standard gas can be made. -
Page 23: Pressure Indication
Technical Information Pressure Indication Ionization gauge controllers measure the positive ion current in amperes from the ion gauge, but the readout is in pressure units. These pressure units are direct reading only for the gas of which is specified - usually nitrogen or air. -
Page 24: Gauge Tube Sensitivity
Chapter 4 To convert the readout to a different gas, the equation must also include gasX, tube 2) Most ion gauge controllers are designed for some calibrated set-point of emission = i_. The emission that corrects for both controller sensitivity and gas type is: Ionization Gauge Instruction Manual - 274026 - Rev. -
Page 25: Gas Sensitivity
Technical Information Gas Sensitivity Table 4-3 lists relative gauge sensitivities (r ) for various gases. The values listed are averages of several gauges and several references from literature (Table II, Ionization Gauge Sensitivities As Reported in the Literature, from NASA Technical Note TND5285 by Robert L. Summers, Lewis Research Center, National Aeronautics and Space Administration). - Page 26 Chapter 4 Figure 4-1 Series 274 Bayard-Alpert Ionization Gauges Tubulated B-A Gauge Nude B-A Gauge UHV Nude B-A Gauge R or EB Degas R or EB Degas EB Degas Nude ion gauge with cable connector strain relief. Nude ion gauge without Catalog numbers: 274041, cable connector strain relief.
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Page 27: Gauge Specifications
Technical Information Gauge Specifications Table 4-4 Series 274 Bayard-Alpert Gauge Physical and Operating Data Physical Data Tubulated Gauge EB Degassable Nude Gauge R Degassable Nude Gauge Tubulation .75 inch (19mm) or 1 inch N.A. N.A. (25mm) dia. x 2.25 inch (57mm ) long, Kovar, Pyrex, or flanged Envelope Nonex 7720 Glass, 2.25 inch... -
Page 28: Service Guidelines
Chapter 4 Service Guidelines For customer service: If the product requires service, contact the MKS, Granville-Phillips Division Customer Service Department at +1-800-227-8766 or +1-303-652-4691 for troubleshooting help over the phone. If the product must be returned to the factory for service, request a Return Material Authorization (RMA) from Granville-Phillips. - Page 29 Instruction Manual part number 274026 Revision B - August 2014...
- Page 30 For Customer Service or Technical Support 24 hours per day, 7 days per week, every day of the year including holidays: Phone: +1-800-227-8766 or +1-303-652-4691 MKS, Granville-Phillips Division 6450 Dry Creek Parkway Longmont, CO 80503 USA Phone: 1-303-652-4691 or 1-800-776-6543...
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