® Bourns Precision Potentiometers and Turns-Counting Dials Short Form Brochure Introduction Bourns has been a pioneer in both wirewound and and a turns-counting dial all in one package. non-wirewound resistive technology for over half Sensors and Controls is dedicated to providing our a century and continues to lead the way in terms customers with reliable precision potentiometer of product innovation and lean manufacturing. solutions. Bourns® Sensors & Controls division offers an assortment of precision potentiometers in sizes In addition to precision potentiometers, Bourns® that range from 22 mm to 51 mm. Both single-turn Sensors & Controls offers a variety of turns- and multiturn styles are available with bushing counting dials. A turns-counting dial is generally and servo mount styles. Some models are available used on the outside of the panel as a precision with Ingress Protection (IP rating) up to IP 68. In potentiometer’s indicating and adjustment setting addition, Bourns offers the Knobpot® model, which device. There are various models available with is a multiturn wirewound precision potentiometer digital or analog (concentric scale) readouts. General Use of Precision Potentiometers Precision potentiometers are generally used in • Must be very accurate circuitry where adjustments to the voltage level or • Require frequent adjustments, and/or current flow: • Where a precise relationship must exist between the shaft rotation and the electrical output Performance Parameters and Technology There are four performance parameters that are Based on your application, you can choose three especially important when choosing a precision different technology classifications of precision potentiometer for your application. They are: potentiometers: wirewound, Hybritron® (wire- • Resolution wound element with conductive polymer coating), • Output smoothness and conductive polymer. • Linearity • Rotational life Custom Solutions A wide range of “value-added” enhancements are • Cable harness/lead wires • Hardware available to provide our customers with cost- • Detents • Marking effective solutions. Bourns’ capability to develop • Custom output • Mechanical stops custom precision potentiometer solutions and • Seal • Mounting brackets modifications include those listed to the right. • Torque • Special test requirements • Special packaging • Customized shaft options For additional information on value-added • Terminal configurations enhancements, please contact your local Bourns Sales Representative or Field Application Engineer. Applications Test & Measurement Applications Medical Applications* Precision • Appliance testers • Blood & chemical analyzers Potentiometers • Battery testers • EKG, EEG heart monitors • Board in-circuit testers • Incubators Medical Applications* • Calibration equipment • Insulin & infusion pumps • Blood bank equipment • Component testers • Isokinetic equipment • Blood monitors • Continuity testers • Keratoscopes • Blood/chemical analyzers • Cycle testers • Kidney machines • Communication equipment • Distortion testers • Lasers • Computer-assisted tomography • Electric motor testers • Magnetic resonance imaging (CAT) equipment • Electrostatic testers (MRI) equipment • Dental chairs • Environmental chambers & • Medical meters • Dialysis equipment testers • Radiographic equipment • EKG, EEG heart monitors • High voltage testers • Respirators • Electrosurgical equipment • Laser, fiber optic testers • Respiratory & temperature • Hospital beds • Light testers monitors • Incubators • Logic & spectrum analyzers • Stimulators • Insulin/infusion pumps • Oscilloscopes • Test equipment • Isokinetic equipment • Power supply testers • Transducer, speech, & hearing • Lasers • Radiation & x-ray testers amplifiers • Magnetic resonance imaging • Signal level testers • Ventilators (MRI) equipment • Telecom line testers • Mobility equipment • Transmission testers Test & Measurement Applications • Radiographic equipment • TV/video generation testers • Cable testers • Respirators • Ultrasonic testers • Counters & timers • Respiratory monitors • Cycle testers • Scanners • Distortion testers • Speech/hearing amplifiers & • Electrostatic testers Turns-Counting Dials transducers • Environmental chambers & • Stimulators testers Telecommunications Applications • Ventilators • High voltage testers • CB & shortwave base stations • X-ray/diagnostic equipment • Logic & spectrum analyzers • Digital television cable boxes • Oscilloscopes • Video-conferencing equipment Industrial Automation & Equipment • Radiation & X-ray testers Applications • Signal level testers Portable Electronics Applications • Appliances • Ultrasonic testers • Data communications • Camera positioning equipment • Forklifts • Data communications testers • Irrigation controllers • Smoke, CO , gas, heat & • Position feedback 2 humidity detectors • Power generators • Household appliances • Robotics • Irrigation controllers • Satellite positioning systems • Measuring equipment • Servo motors • Portable test equipment • Welding equipment • Telecommunications equipment • Verification equipment * Excluding critical life support applications Precision Potentiometer Selection Guide The following flowcharts will help you to select the best precision potentiometer and turns-counting dial for your Potentiometer Request precision application. Element Type Non-Wirewound Wirewound Technology Technology Mounting Hybritron® Standard 3 Turns 3 Turns Servo 5 Turns 5 Turns Bushing 10 Turns 10 Turns ** ** 6630 6537 3501 3548H 3547H 3540 3545 3543 ** 6639 6538 3541 3549S 3548S 3547S ** 6637 6539 3549H 3590 6638 6574 3701H 3700 * * 6657 6534 3751H 3750 * Servo mount ** Standard servo mount option available Turns-Counting Dial Selection Guide Turns-Counting Dial Request Number of Turns Up to Up to Up to 10 15 30 Shaft Acceptance Shaft Acceptance Shaft Acceptance Diameter Diameter Diameter 1/8 “ 1/4 “ 1/8 “ 6 mm 6 mm 1/4 ” 1/4 “ CT-23 CT-23 H-46 H-46 H-22 H-490 H-490 CT-26 CT-26 H-22 H-22 H-23 H-23 H-23 H-506 H-506 ® Bourns Precision Potentiometers Features Number of Turns 10 • Bushing mount Rotational Life 2M Shaft Revolutions • Optional –0.05 linearity option Element Wirewound • Excellent wiper stability Noise/Output Smoothness 100 Ω max. • High stop strength Operating Temp. Range -40 to +125 °C • Sealable Power Rating 5 watts • RoHS compliant versions available* Independent Linearity ±0.15 % 3400 IP Rating 40 Features Number of Turns 10 • Bushing mount Rotational Life 2M to 4M Shaft Revolutions • Sealable Element Wirewound or Hybritron® • Non-standard features and specifications available Noise/Output Smoothness 100 Ω max. / 0.1 % max. • Optional high torque feature Operating Temp. Range -40 to +125 °C • Optional center tap feature Power Rating 2 watts • Gangable Independent Linearity ±0.20 % to ±0.25 % 3500/3501 • RoHS compliant versions available* IP Rating 65 Features Number of Turns 10 • Bushing mount • High torque available Rotational Life 1M to 5M Shaft Revolutions • Optional center tap and rear  • Non-standard features  Element Wirewound or Hybritron® shaft extension and specifications  Noise/Output Smoothness 100 Ω max. / 0.1 % max. • Optional AR lug feature available Operating Temp. Range -40 to +125 °C • Gangable with common or  • RoHS compliant versions  Power Rating 2 watts concentric shafts available* Independent Linearity ±0.25 % 3540/3541 IP Rating 40 Features Number of Turns 3 to 5 • Bushing mount Rotational Life 300K to 500K Shaft Revolutions • Optional AR pin feature Element Wirewound • Non-standard features and specifications available Noise/Output Smoothness 100 Ω max. • Gangable Operating Temp. Range -40 to +125 °C • RoHS compliant versions available* Power Rating 1 to 1.5 watts Independent Linearity ±0.25 % 3543/3545 IP Rating 40 Features Number of Turns 3 • Wirewound and Hybritron®  • Designed for HMI and  Rotational Life 750K to 1.5M Shaft Revolutions elements MMI applications Element Wirewound or Hybritron® • High rotational life • Dual gang option Noise/Output Smoothness 100 Ω max. / 0.15 % max. • Optional 0.20 % linearity • Servo mount option Operating Temp. Range -40 to +125 °C • Optional AR lug • RoHS compliant* Power Rating 1 watt • Suitable for use under side  Independent Linearity ±0.20 % to ±0.25 % 3547 load IP Rating 50 *RoHS Directive 2002/95/EC Jan 27 2003 including Annex. Features Number of Turns 5 • Wirewound and Hybritron®  • Designed for HMI and  Rotational Life 1M to 2.5M Shaft Revolutions elements MMI applications Element Wirewound or Hybritron® • High rotational life • Dual gang option Noise/Output Smoothness 100 Ω max. / 0.15 % max. • Optional 0.15 % linearity • Servo mount option Operating Temp. Range -40 to +125 °C • Optional AR lug • RoHS compliant* Power Rating 1.5 watt • Suitable for use under side  Independent Linearity ±0.15 % to ±0.25 % 3548 load IP Rating 50 Features Number of Turns 10 • Wirewound and Hybritron®  • Designed for HMI and  Rotational Life 2M to 5M Shaft Revolutions elements MMI applications Element Wirewound or Hybritron® • High rotational life • Dual gang option Noise/Output Smoothness 100 Ω max. / 0.10 % max. • Optional 0.1 % linearity • Servo mount option Operating Temp. Range -40 to +125 °C • Optional AR lug • RoHS compliant* Power Rating 2 watts • Suitable for use under side  Independent Linearity ±0.10 % to ±0.20 % 3549 load IP Rating 50 Features Number of Turns 10 • Bushing mount • Designed for use in HMI  Rotational Life 1M Shaft Revolutions • Optional AR lug applications Element Wirewound • Plastic or metal shaft and  • RoHS compliant versions  Noise/Output Smoothness 100 Ω max. bushings available* Operating Temp. Range -40 to +125 °C • Wirewound Power Rating 2 watts • Solder lugs or PC pins Independent Linearity ±0.25 % 3590 • Sealable (Full body seal) IP Rating 40 or 65 Features Number of Turns 10 • Bushing mount Rotational Life 1M to 4M Shaft Revolutions • Excellent resolution Element Wirewound or Hybritron® • Non-standard features and specifications available Noise/Output Smoothness 500 Ω max. / 0.10 % max. • Small diameter Operating Temp. Range -40 to +105 °C • High rotational life Power Rating 1 watt • RoHS compliant versions available* Independent Linearity ±0.25 % 3700/3701 IP Rating 40 Features Number of Turns 10 • Servo mount Rotational Life 1M to 10M Shaft Revolutions • Excellent resolution Element Wirewound or Hybritron® • Non-standard features and specifications available Noise/Output Smoothness 500 Ω max. / 0.15 % max. • Small diameter Operating Temp. Range -40 to +105 °C • High rotational life Power Rating 1 watt • RoHS compliant versions available* Independent Linearity ±0.25 % 3750/3751 IP Rating 40 *RoHS Directive 2002/95/EC Jan 27 2003 including Annex. ® Bourns Precision Potentiometers (Continued) Features Number of Turns Continuous • Servo mount Rotational Life 25M Shaft Revolutions • Shaft support by front and rear precision ball bearings Element Conductive Plastic • Non-standard features and specifications available Output Smoothness 0.10 % • Gangable up to 10 cups Operating Temp. Range -40 to +125 °C • RoHS compliant* Power Rating 1 watt Independent Linearity ±0.50 % 6534 IP Rating 40 Features Number of Turns Continuous (stops available) • Lower profile than Model 6639 • Cost and space saving Rotational Life 5M Shaft Revolutions • Essentially infinite resolution • Molded-in rear terminals Element Conductive Plastic • Excellent rotational life • Non-standard features &  Output Smoothness 0.10 % • High quality, rugged                 specifications available Operating Temp. Range -40 to +125 °C construction • Anti-rotation lug option Power Rating 1 watt • Recommended for HMI  • Mechanical stop option Independent Linearity ±2.0 % 6630 applications • RoHS compliant* IP Rating 40 Features Number of Turns Continuous • Infinite resolution element • Molded-in rear  Rotational Life 10M to 20M Shaft Revolutions • Standard linearity: 1.0 % terminals Element Conductive Plastic • Extended temperature range:              • Non-standard features  Output Smoothness 0.10 % -65 °C to +125 °C and specifications  Operating Temp. Range -40 to +125 °C • Extended life version (6538) available Power Rating 1 watt • Output smoothness:              • RoHS compliant* Independent Linearity ±1.0 % to ±1.5 %  6537/6538 0.1 % standard IP Rating 40 Features Number of Turns Continuous • Essentially infinite resolution Rotational Life 10M Shaft Revolutions • Excellent rotational life Element Conductive Plastic • High quality, rugged construction Output Smoothness 0.10 % • General purpose applications Operating Temp. Range -40 to +125 °C • Non-standard features available Power Rating 1 watt • Cost and space saving Independent Linearity ±2.0 %  6539/6639 • RoHS compliant* IP Rating 40 Features Number of Turns Continuous • Servo mount style Rotational Life 25M Shaft Revolutions • Shaft supported by front and rear precision ball bearings Element Conductive Plastic • Non-standard features and specifications available Output Smoothness 0.10 % • Gangable up to 10 cups Operating Temp. Range -40 to +125 °C • RoHS compliant* Power Rating 2 watts Independent Linearity ±0.25 %  6574 IP Rating 40 *RoHS Directive 2002/95/EC Jan 27 2003 including Annex. Features Number of Turns Continuous • Bushing mount Rotational Life 10M Shaft Revolutions • Excellent resolution Element Conductive Plastic • High rotational life Output Smoothness 0.10 % • Non-standard features and specifications available Operating Temp. Range -40 to +125 °C • RoHS compliant* Power Rating 1 watt Independent Linearity ±1.0 %  6637 IP Rating 40 Features Number of Turns Continuous • 7/8 ” (22 mm) diameter single turn conductive plastic Rotational Life 20M Shaft Revolutions • Bushing mount Element Conductive Plastic • Excellent resolution Output Smoothness 0.10 % • High rotational life – ball bearing shaft support Operating Temp. Range -40 to +125 °C • Non-standard features and specifications available Power Rating 1 watt • RoHS compliant* Independent Linearity ±1.0 %  6638 IP Rating 40 Features Number of Turns Continuous • Bushing mount Rotational Life 10M Shaft Revolutions • Shaft supported by front sleeve bearing Element Conductive Plastic • Non-standard features and specifications available Output Smoothness 0.10 % • RoHS compliant* Operating Temp. Range -40 to +125 °C Power Rating 1.5 watt Independent Linearity ±1.0 %  6657 IP Rating 40 Features Number of Turns Continuous • 51 mm (2 “) diameter,  • Gangable up to 10 cups Rotational Life 25M Shaft Revolutions single-turn conductive  • Non-standard features and  Element Conductive Plastic plastic specifications available Output Smoothness 0.10 % • Excellent resolution • Ball bearings Operating Temp. Range -40 to +125 °C • High rotational life • RoHS compliant* Power Rating 2 watts • Bushing mount Independent Linearity ±0.25 %  6674 IP Rating 40 *RoHS Directive 2002/95/EC Jan 27 2003 including Annex. ® Bourns Precision Potentiometers (Continued) Features Number of Turns 10 • Snap-in mounting Rotational Life 50K Shaft Revolutions • Space saving - extends only 5/8 ” behind most panels Element Wirewound • Easy one-hole, snap-in mounting Noise 100 Ω max. • Digital dial provides excellent readability Operating Temp. Range +1 to +85 °C Power Rating 1.5 watts Accuracy (Dial Reading to Output Ratio) ±0.50 % Voltage Ratio 3610 (Knobpot®) IP Rating 60 Features Number of Decades 2 to 5 • Repeatable settings Rotational Life 75K Button Operations Each Decade • Resolution to 0.001 % Element Cermet • Digital display provides excellent readability Operating Temp. Range -25 to +85 °C • Snap-in panel mount Power Rating 2 watts • RoHS compliant versions available* Accuracy (Dial Reading to Output Ratio) ±1 % Full Scale IP Rating 40 3680 *RoHS Directive 2002/95/EC Jan 27 2003 including Annex. Turns-Counting Dials Features Number of Turns 0-15 • No backlash • Improved brake to  Locking Brake Yes • Compact - requires minimal  provided higher torque Division per Turn 50 panel space (22.2 mm  • Contoured grip knob Readout Concentric Scale diameter) Shaft Acceptance Diameter 6.35 mm (0.250 “), 6.00 mm (0.236 “),  • For use with precision  3.175 mm (0.125 “) potentiometers or other  Base Material Metal H-22 rotary devices up to 15 turns RoHS Compliant* Yes Features Number of Turns 0-15 • No backlash • Designed for metal shaft Locking Brake Yes • Compact - requires minimal  • Improved brake to  Division per Turn 50 panel space (22.2 mm  provided higher torque Readout Concentric Scale diameter) • Contoured grip knob Shaft Acceptance Diameter 6.35 mm (0.250 “), 6.00 mm (0.236 “),  • For use with precision  3.175 mm (0.125 “) potentiometers or other  Base Material Metal H-23 rotary devices up to 15 turns RoHS Compliant* Yes Features Number of Turns 0-15 • Compact- requires only  • Designed for plastic  Locking Brake Yes 22.7 mm diameter panel  shaft Division per Turn 50 space Readout Concentric Scale • No backlash Shaft Acceptance Diameter 6.35 mm (0.250 “), 6.00 mm (0.236 “) • For use with precision  Base Material Plastic potentiometers or other  RoHS Compliant* Yes H-506 rotary devices up to 15 turns Features Number of Turns 0-10 • 27 & 28 mm diameter • For use with precision  Locking Brake Yes • No backlash - mounted  potentiometers or other  Division per Turn 50 directly to potentiometer  rotary devices up to  Readout Digital shaft 10 turns Shaft Acceptance Diameter 6.35 mm (0.250 “), 6.00 mm (0.236 “) • High force, positive brake • Compact- requires only  Base Material Plastic 22.7 mm diameter panel  RoHS Compliant* Yes CT-23/CT-26 space Features Number of Turns 0-30 • No backlash - mounted  • Compact- requires only  Locking Brake Yes directly to potentiometer  22.7 mm diameter panel  Division per Turn 100 shaft space Readout Concentric Scale • For use with precision  • Available with or without  Shaft Acceptance Diameter 6.35 mm (0.250 “), 3.175 mm (0.125 “) potentiometers or other  brake Base Material Plastic rotary devices up to  RoHS Compliant* Yes H-490 30 turns *RoHS Directive 2002/95/EC Jan 27 2003 including Annex. 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Specifications subject to change without notice. Actual performance in specific customer applications may differ due to the  influence of other variables. Customers should verify actual device performance in their specific applications. BOURNS® “Bourns”, “Hybritron” and “Knobpot” are registered trademarks of Bourns, Inc. in the U.S. and other countries. COPYRIGHT© 2010, BOURNS, INC. • LITHO IN U.S.A. • WAG • 03/10 • 5M/SC1021