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Handbook of Photoelectric Sensing

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Handbook of Photoelectric Sensing Handbook of Photoelectric Sensing Banner Engineering Corp. Minneapolis, MN Handbook of Photoelectric Sensing Copyright © 1993 Banner Engineering Corp. All rights reserved. Second Edition, First Printing Printed in the United States of America Banner Engineering Corp. 9714 Tenth Avenue North Minneapolis, MN 55441 (612) 544-3164 Handbook of Photoelectric Sensing Introduction Section A: Sensing Theory Sensor Types .......................................................... A-1 VALU-BEAM® Self-contained Sensors ............ B-53 Fiber Optics ............................................................ A-4 Q85 Series Sensors ............................................ B-53 Sensing Modes ....................................................... A-6 OMNI-BEAM™ Self-contained Sensors .......... B-54 Beam Patterns ......................................................... A-12 Sonic OMNI-BEAM™ Self-contained Sensors . B-54 Excess Gain ............................................................ A-14 MAXI-BEAM® Self-contained Sensors ............ B-55 Contrast ............................................................ A-18 MULTI-BEAM® Self-contained Sensors .......... B-55 Sensor Outputs ....................................................... A-22 ULTRA-BEAM™ Self-contained Sensors ....... B-56 Sensing Response Time .......................................... A-22 Sensor Housing and Lens Material ....................... B-56 Category C - Electrical Considerations Section B: Sensor Selection Sensor Supply Voltage ......................................... B-60 Introduction ............................................................ B-1 Sensor Interface ................................................... B-68 Category A - Sensing Mode Sensor Switching Speed ....................................... B-72 Photoelectric Sensing Modes Sensor Diagnostic Feedback ................................ B-72 Opposed Mode Sensing ..................................... B-2 Category D - Environmental Considerations Retroreflective Mode Sensing ........................... B-7 Temperature ......................................................... B-75 Photoelectric Proximity Mode Sensing.............. B-10 Moisture ............................................................ B-76 Fiber Optic Modes............................................. B-17 Corrosive Agents ................................................. B-77 Ultrasonic Proximity Sensing Mode ..................... B-22 Dirt, Dust, Fog ..................................................... B-77 Application-specific Sensing Modes Air Turbulence ..................................................... B-78 Optical Edgeguiding .......................................... B-24 Vibration and Shock ............................................ B-79 Optical Data Transmission ................................ B-25 Hazardous Environments ..................................... B-80 Measurement Light Curtain ............................... B-26 Vacuum Feedthroughs ......................................... B-83 Parts Sensing Light Curtain ............................... B-27 Electrical Noise .................................................... B-83 Count Totalizing ............................................... B-28 Clear Plastic Detection ...................................... B-29 Category E - Sensor Cost Ambient Light Detection ................................... B-29 Sensing Mode ...................................................... B-85 Color Mark Detection ........................................ B-31 Sensor Supply Voltage ......................................... B-85 Close-differential Sensing ................................. B-34 Sensor Family ...................................................... B-85 Personnel Safety ................................................ B-35 Optical Touch Buttons....................................... B-37 Section C: Interfacing Switched Outputs Category B - Sensor Package Electromechanical Relays .................................... C-1 Sensor Type Solid-state Relays Self-contained Sensors ...................................... B-38 Interfacing DC Sensors to DC Loads Remote Sensors ................................................. B-44 Current Sinking Outputs ................................. C-5 Sensor Size Current Sourcing Outputs ............................... C-8 Plastic Fiber Optics ........................................... B-46 Isolated Transistor Output............................... C-8 Glass Fiber Optics ............................................. B-46 Interfacing DC Sensors to AC Loads ................. C-9 SP100 Series Remote Sensors ........................... B-47 Interfacing AC Sensors to AC Loads Modulated Remote Sensors ............................... B-48 2-wire Sensors ................................................ C-10 QØ8 Series Sensors ........................................... B-49 3-wire Sensors ................................................ C-12 Q19 Series Sensors ............................................ B-49 3- and 4-wire Sensors ..................................... C-12 S18 Series Threaded Barrel Sensors .................. B-49 Interfacing AC Sensors to DC Loads ................. C-12 ECONO-BEAM™ Self-contained Sensors ....... B-50 Analog Outputs MINI-BEAM™ Self-contained Sensors ............ B-51 OMNI-BEAM® with Analog Output ................... C-14 SM512 Series Sensors ....................................... B-52 ULTRA-BEAM™ with Analog Output ............... C-15 SM30 Series Barrel Sensors .............................. B-52 Sonic OMNI-BEAM™ with Analog Output ........ C-16 Hookup Diagrams AND Logic .......................................................... D-12 OMNI-BEAM™ DC Power Blocks..................... C-18 Anti-bounce Logic ............................................... D-12 OMNI-BEAM™ AC Power Blocks..................... C-19 ® Dual Channel Inverter .......................................... D-12 MULTI-BEAM DC Power Blocks .................... C-20 Notes Regarding Logic Module Inputs ................... D-12 MULTI-BEAM® 4-wire AC Power Blocks ......... C-21 MULTI-BEAM® 2-wire AC Power Blocks ......... C-22 Section E: Troubleshooting MAXI-BEAM® DC Power Blocks ...................... C-23 MAXI-BEAM® 4-wire AC Power Blocks ........... C-24 Introduction ............................................................ E-1 MAXI-BEAM® 2-wire AC Power Blocks ........... C-25 Problem Symptoms and Probable Causes ............... E-4 VALU-BEAM® SM912 Series DC Sensors ........ C-26 Troubleshooting References VALU-BEAM® SM2A912 Series AC Sensors .... C-27 Wiring and Interface Problems VALU-BEAM® 915 and 990 Series Sensors ....... C-28 Supply Voltage .................................................. E-7 VALU-BEAM® SMI912 Series Bad Connections ............................................... E-7 Intrinsically Safe DC Sensors ............................ C-28 Improper Grounds ............................................. E-7 MINI-BEAM® SM312 Series DC Sensors ......... C-29 Voltage Surges, Spikes, and DVDT .................. E-8 MINI-BEAM® SM2A312 Series AC Sensors ..... C-30 AC Shorted Load and Overload ........................ E-8 ECONO-BEAM™ Miniature DC Sensors ........... C-31 Leakage Current ................................................ E-9 QØ8 Series Miniature DC Sensors ....................... C-32 DC Short-circuit Protection Circuitry ................ E-9 Q19 Series DC Sensors ........................................ C-33 Saturation Voltage ............................................. E-10 SM512 Series Sensors .......................................... C-34 Faulty DC Power Sources ................................. E-10 SM30 Series DC Sensors ..................................... C-35 Amplifer Response to Electrical Crosstalk ........ E-11 SM30 Series AC Sensors ..................................... C-36 S18 Series DC 18-mm Barrel Sensors .................. C-37 Sensing Component Failures S18 Series AC 18-mm Barrel Sensors .................. C-37 Infant Mortality ................................................. E-11 C3Ø Series Sensors .............................................. C-38 Failed Remote Emitter or Receiver.................... E-11 Q85 Series AC/DC Sensors ................................. C-38 Failed Electromechanical Output Relay............. E-12 ULTRA-BEAM™ 925 Series Ultrasonic Sensors .... C-39 Broken Alignment LED .................................... E-12 ULTRA-BEAM™ 923 Series Ultrasonic Sensors .... (C-15) Lens Corrosion .................................................. E-12 E-series OMNI-BEAM™ Sensors ....................... C-39 Discolored or Cracked Lenses ........................... E-12 Sonic OMNI-BEAM™ Sensors ........................... C-39 Retro Target Obscured or Broken ...................... E-12 MAXI-AMP™ Modulated Amplifiers ................. C-40 Broken Fiber Optics .......................................... E-13 ® MICRO-AMP Modulated Amplifiers ................ C-40 Sensing Timing Problems Response Time .................................................. E-13 Section D: Sensing Logic Interrogation Timing ......................................... E-13 Multiple Sensor Hookup Behavior on Power-up ....................................... E-13 Introduction ......................................................... D-1 Marginal Sensing Conditions Sensors with Electromechanical Output Relay ..... D-2 Low Sensing Contrast ....................................... E-14 Sensors with Solid-state Output Relay
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