oH V SC AV ER OM AI SIO PL LA N IA BL S NT E *R Features ■ ■ ■ ■ ■ ■ Single-turn (3851 and 3852) Linear and audio tapers 3-3/4-turn (3856) Wide resistance range Minimal depth package Good resolution Non-RoHS compliant versions are currently available, although not recommended for new designs. 3851/3852/3856 - 3/4 ” Diameter Panel Control Initial Electrical Characteristics1 3851 Conductive Plastic Element 3852/3856 Cermet Element Standard Resistance Range Linear Tapers (A, B, E, and H) ............................................................1 K to 1 megohm.........................................100 ohms to 1 megohm Audio Tapers (C, D, F, and G) .............................................................1 K to 1 megohm.........................................1 K ohms to 1 megohm Total Resistance Tolerance .....................................................................±10 % or ±20 %..........................................±5 % or ±10 % Independent Linearity .............................................................................±10 %..........................................................(A & H tapers) ±5 % Absolute Minimum Resistance ...............................................................2 ohms maximum........................................ 2 ohms maximum Effective Electrical Angle ........................................................................250 ° ±5 °.....................................................250 ° ±5 ° Contact Resistance Variation .................................................................±1 %............................................................±3 % of total resistance or 3 ohms (whichever is greater) Dielectric Withstanding Voltage (MIL-STD-202, Method 301) Sea Level............................................................................................900 VAC minimum.......................................900 VAC minimum 70,000 Feet ........................................................................................350 VAC minimum.......................................350 VAC minimum Insulation Resistance (500 VDC) ............................................................1,000 megohms minimum...........................1,000 megohms minimum Power Rating (Voltage Limited By Power Dissipation or 350 VAC, Whichever Is Less) +70 °C ...............................................................................................(Linear tapers) 1 watt...................................(Linear tapers) 2 watts (Audio tapers) 0.5 watt (Audio tapers) 1 watt +125 °C ..............................................................................................0 watt +150 °C ...................................................................................................................................................................0 watt Theoretical Resolution ............................................................................Essentially infinite ........................................Essentially infinite Environmental Characteristics1 Operating Temperature Range ...............................................................-1 °C to +125 °C..........................................-1 °C to +125 °C Storage Temperature Range...................................................................-65 °C to +125 °C........................................-65 °C to +150 °C Temperature Coefficient Over Storage Temperature Range...................±1,000 ppm/°C............................................±150 ppm/°C Vibration..................................................................................................20 G.............................................................20 G Total Resistance Shift.........................................................................±2 % maximum ...........................................±2 % maximum Voltage Ratio Shift..............................................................................±5 % maximum ...........................................±6 % maximum Shock......................................................................................................100 G...........................................................100 G Total Resistance Shift.........................................................................±2 % maximum ...........................................±2 % maximum Voltage Ratio Shift..............................................................................±5 % maximum ...........................................±6 % maximum Load Life.................................................................................................1,000 hours .................................................1,000 hours Total Resistance Shift.........................................................................±10 % maximum .........................................±3 % maximum Rotational Life (No Load) ........................................................................100,000 cycles ............................................50,000 cycles Total Resistance Shift.........................................................................±15 % TRS maximum ................................±5 % or 5 ohms TRS whichever is greater Contact Resistance Variation .............................................................±3 %............................................................±3 % Moisture Resistance (MIL-STD-202, Method 103, Condition B) Total Resistance Shift.........................................................................±10 % maximum ........................................±2 % maximum IP Rating .................................................................................................IP 40 ............................................................IP 40 Mechanical Characteristics1 Stop Strength ..............................................................................................................................................................................................56.5 N-cm (5 lb.-in.) Mechanical Angle ....................................................................................................................................................................280 ° ±5 ° / 3856 – 1350 ° ±50 ° Torque (Starting and Running) ..............................................................................................................A & B bushings 0.35 to 4.23 N-cm (0.05 to 6.0 oz.-in.) C & E bushings 0.21 to 4.23 N-cm (0.3 to 6.0 oz.-in.) 3856 – 0.11 to 2.12 N-cm (0.15 to 3.0 oz.-in.) Mounting (Torque on Bushing) ......................................................................................................................................1.7-2.0 N-m (15-18 lb.-in.) maximum Weight (Single Section) ................................................................................................................................................................................30 grams maximum Terminals ........................................................................................................................................................................Printed circuit terminals or solder lugs Soldering Condition ......................................................................Recommended hand soldering using Sn95/Ag5 no clean solder, 0.025 ” wire diameter. Maximum temperature 399 °C (750 °F) for 3 seconds. No wash process to be used with no clean flux. Part can be wave soldered at 260 °C (500 °F) for 5 seconds, no wash process with no clean flux. Marking....................................................................................................Manufacturer’s trademark, wiring diagram, resistance, date code, and part number Ganging (Multiple Section Potentiometers) ......................................................................................................................................................1 cup maximum Hardware ............................................One lockwasher and one mounting nut is shipped with each potentiometer, except where noted in the part number. 1 AT ROOM AMBIENT: +25 °C NOMINAL AND 50 % RELATIVE HUMIDITY NOMINAL, EXCEPT AS NOTED. *RoHS Directive 2002/95/EC Jan 27 2003 including Annex Specifications are subject to change without notice. Customers should verify actual device performance in their specific applications. 3851/3852/3856 - 3/4 ” Diameter Panel Control Product Dimensions 3851B/3852B 3851A/3852A 12.7, 22.23 STD. (1/2, 7/8) 9.53 (.38) 6.35 ± .76 (.25 ± .03) 3/8-32 UNEF .25 45 ° X (.010) CHAMFER .38 (.015) 19.05 (.75) DIA. 6.35+.03/-.05 DIA. (.250+.001/-.002) 6.35 ± .76 (.25 ± .03) 3/8-32 UNEF .25 45 ° X (.010) CHAMFER .38 (.015) 19.05 (.75) DIA. SHAFT SLOT 1.19 WIDE X .047 1.60+.38/.00 DEEP (.063+.015/-.000) 12.19 DIA. (.480) 15.88 STD. (5/8) 12.7 (.50) 6.35+.03/-.05 DIA. (.250+.001/-.002) SHAFT SLOT 1.19 WIDE X (.047) 1.60+.38/-.00 (.063+.015/-.000)DEEP 12.19 DIA. (.48) 16.00 5.49 OPTIONAL FLAT (.63) (.216) 1.52 28.58 LONG OR FRONT BUSHING FOR SHAFTS UNDER (.06) (1-1/8) Terminal Configuration SOLDER LUG TERMINAL 6.35 2.79 (.25) TYP. (.110) 3 PLCS. 12.7 (.50) EACH TERMINAL LUG 2 3 2 PLCS. 1 WILL ACCOMMODATE .81 THREE (.032) DIAMETER 14.02 ± .25 (.812 DIA. AWG (.552 ± .010) STRANDED) WIRES. STANDARD PRINTED CIRCUIT TERMINAL 1.02 6.35 TYP. TYP. (.040) (.25) 15.88 ± .38 (.625 ± .015) 3851C/3852C 9.53, 22.23 STD. (3/8, 7/8) 6.35 (.25) 6.35 ± .76 (.25 ± .03) 1/4-32 UNEF .25 45 ° X (.010) CHAMFER .38 (.015) 2.36 (.094) 19.05 (.75) DIA. .25 45 ° X (.010) CHAMFER 19.05 (.75) DIA. SHAFT SLOT .79 .76 WIDE X DEEP (.03) (.031) .25 OPTIONAL FLAT LONG OR (.010) 1.52 15.88 FRONT BUSHING FOR SHAFTS UNDER (.06) (5/8) 1.40 DIA. (.055) 3.18 ± .025 DIA. (.125 ± .001) SHAFT SLOT .79 .76 WIDE X DEEP (.031) (.03) 9.53 (.38) 6.35 ± .76 (.25 ± .03) 3856H 12.7 (.50) 3851/3852/3856 A, B & H BUSHINGS 9.53 (.375) .38 (.015) 6.35 ± .76 (.25 ± .03) 1.19 (.047) 19.05 (.75) DIA. 12.19 DIA. (.480) 1.60+3.81/-.000 (.063+.015/-.000) DIA. 6.35+.03/-.05 DIA. (.250 ± .03) 3/8-32 UNEF. .79 (.031) 3/8-32 UNEF 9.53 (.375) 3.18 DIA. (.125) 3.18 6.73 DIA. (.125) DIA. (.265) Shaft End Detail 3850 Family 12.7 (.50) 9.53 (.38) 6.35+.03/-.05 DIA. (.250+.001/-.002) .38 (.015) 6.35 (.25) SUGGESTED BOARD LAYOUT 6.35 6.35 (.25) (.25) 10.31 DIA. (.406) 3856A 3 1/4-32 UNEF .38 (.015) 12.19 DIA. (.480) 2 12.7 STD. (1/2) 9.53 (.38) 6.35 ± .76 (.25 ± .03) 3.18 ± 0.25 DIA. (.125 ± .001) 12.19 DIA. (.480) 1 3851E/3852E SHAFT SLOT ALIGNMENT AT CCW FLAT ALIGNMENT AT CCW 50 ° ± 10 ° 19.05 (.75) DIA. 12.19 DIA. (.480) .25 45 ° X (.010) CHAMFER .79 ± .25 (.031 ± .010) 22.23 STD. (7/8) 22.23 STD. (7/8) DIMENSIONS ARE: Specifications are subject to change without notice. Customers should verify actual device performance in their specific applications. MM (INCHES) 3.18 ± .03 (.125 ± .003) DIA. .25 45 ° X (.010) CHAMFER TOLERANCES EXCEPT AS NOTED: .127 .38 DECIMALS: .XXX ± .XX ± (.015) (.005), FRACTIONS: ± 1/64 ANGLE: ± 3 % 50 ° ± 10 ° 3851/3852/3856 - 3/4 ” Diameter Panel Control How To Order 3852 12 16 16 20 A - SHAFT TYPE (FMS) & DIAMETER 3/8 ” (9.53 mm) L X 1/8 ” (3.18 mm) D 1/2 ” (12.7 mm) L x 1/4 ” (6.35 mm) D 1/2 ” (12.7 mm) L x 1/8 ” (3.18 mm) D 5/8 ” (15.88 mm) L X 1/4 ” (6.35 mm) D 28 7/8 ” (22.20 mm) L X 1/4 ” (6.35 mm) D 28 7/8 ” (22.20 mm) L X 1/8 ” (3.18 mm) D 28 2 - 103 AVAILABLE ONLY IN MODELS BUSHINGS 3851, 3852 C 3851, 3852 A 3851, 3852 C, E 3851, 3852 A, B 3851, 3852 A, B 3856 A 3851, 3852 C, E 3856 H Consult factory for lengths not shown. A B C E H BUSHING Plain 3/8 ” (9.53 mm) D x 3/8 ” (9.53 mm) L Locking 3/8 ” (9.53 mm) D x 1/2 ” (12.7 mm) L Plain 1/4 ” (6.35 mm) D x 1/4 ” (6.35 mm) L Locking 1/4 ” (6.35 mm) D x 1/2 ” (12.7 mm) L Plain 3/8 ” (9.53 mm) D x 3/8 ” (9.53 mm) L MODEL 3851 3/4 ” (19.05 mm) D Single-Turn C.P. 3852 3/4 ” (19.05 mm) D Single-Turn Cermet 3856 3/4 ” (19.05 mm) D 3-3/4-Turn Cermet Boldface features are Bourns standard options. All others are available with higher minimum order quantities. APPLICABLE MODELS 3851, 3852, 3856 3851, 3852 3851, 3852 3851, 3852 3856 (3.18 mm D Shaft) TERMINAL STYLE AND SHAFT TYPE 1 2 3 5 6 7 Solder Lugs, Plain End Solder Lugs, Slotted End Solder Lugs, Flatted Shaft PC Pins, Plain End PC Pins, Slotted End PC Pins, Flatted Shaft A L RESISTANCE CODE/VALUE (IN OHMS) Model 3851 (102) 1K (252) 2.5 K (502) 5K (103) 10 K (253) 25 K (503) 50 K (104) 100 K (254) 250 K (504) 500 K (105) 1M Models 3852/3856 (101) 100 (251) 250 (501) 500 (102) 1K (252) 2.5 K (502) 5K (103) 10 K (253) 25 K (503) 50 K (104) 100 K (254) 250 K (504) 500 K (105) 1M A B C D E F G H RoHS IDENTIFIER L Compliant Blank Non-Compliant ELEMENT TAPER/TOLERANCE Linear ±10 % Linear ±20 % Audio CW ±10 % Audio CW ±20 % Linear ±10 % Audio CCW ±10 % Audio CCW ±20 % Linear ±5 % APPLICABLE MODELS 3852, 3856 3851 3852, 3856 3851 3851 3852, 3856 3851 3852, 3856 REV. 10/08 Specifications are subject to change without notice. Customers should verify actual device performance in their specific applications.