oH V SC AV ER OM AI SIO PL LA N IA BL S NT E
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.
*R
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
3851A/3852A
9.53 (.38) 6.35 ± .76 (.25 ± .03) .38 (.015) 12.7, 22.23 STD. (1/2, 7/8) 3/8-32 UNEF .25 45 ° X (.010) CHAMFER 6.35+.03/-.05 DIA. (.250+.001/-.002) SHAFT SLOT 1.19 WIDE X .047 1.60+.38/.00 DEEP (.063+.015/-.000) 6.35 ± .76 (.25 ± .03)
3851B/3852B
12.7 (.50) .38 (.015)
15.88 STD. (5/8) 3/8-32 UNEF .25 45 ° X (.010) CHAMFER 6.35+.03/-.05 DIA. (.250+.001/-.002) SHAFT SLOT 1.19 WIDE X (.047) 1.60+.38/-.00 (.063+.015/-.000)DEEP
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.
19.05 (.75) DIA.
19.05 (.75) DIA.
12.19 DIA. (.480)
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)
STANDARD PRINTED CIRCUIT TERMINAL 1.02 6.35 TYP. TYP. (.040) (.25)
15.88 ± .38 (.625 ± .015)
3851C/3852C
6.35 (.25) 6.35 ± .76 (.25 ± .03) .38 (.015) 2.36 (.094) 9.53, 22.23 STD. (3/8, 7/8)
1/4-32 UNEF .25 45 ° X (.010) CHAMFER
3851E/3852E
9.53 (.38) 6.35 ± .76 (.25 ± .03) .38 (.015)
1
2
3
6.35 (.25)
12.7 STD. (1/2)
1/4-32 UNEF
.25 45 ° X (.010) CHAMFER
19.05 (.75) DIA.
19.05 (.75) DIA. 3.18 ± 0.25 DIA. (.125 ± .001) 3.18 ± .025 DIA. (.125 ± .001) SHAFT SLOT .79 .76 WIDE X DEEP (.031) (.03)
SUGGESTED BOARD LAYOUT 6.35 6.35 (.25) (.25) 1.40 DIA. (.055)
12.19 DIA. (.480)
SHAFT SLOT .79 .76 WIDE X DEEP (.03) (.031)
12.19 DIA. (.480)
3851/3852/3856
A, B & H BUSHINGS 9.53 (.375) 9.53 (.375)
.25 OPTIONAL FLAT LONG OR (.010) 1.52 15.88 FRONT BUSHING FOR SHAFTS UNDER (.06) (5/8)
10.31 DIA. (.406)
3.18 DIA. (.125)
3.18 6.73 DIA. (.125) DIA. (.265)
3856A
9.53 (.38) 6.35 ± .76 (.25 ± .03) .38 (.015)
12.7 (.50) 6.35+.03/-.05 DIA. (.250+.001/-.002)
3/8-32 UNEF
3856H
9.53 (.38) 6.35 ± .76 (.25 ± .03) .38 (.015)
12.7 (.50) 6.35+.03/-.05 DIA. (.250 ± .03)
3/8-32 UNEF. .79 (.031)
Shaft End Detail 3850 Family
SHAFT SLOT ALIGNMENT AT CCW FLAT ALIGNMENT AT CCW
19.05 (.75) DIA. 12.19 DIA. (.480) 1.60+3.81/-.000 (.063+.015/-.000) DIA. 22.23 STD. (7/8)
1.19 (.047)
50 ° ± 10 °
50 ° ± 10 °
19.05 (.75) DIA. 12.19 DIA. (.480) .79 ± .25 (.031 ± .010) 22.23 STD. (7/8) 3.18 ± .03 (.125 ± .003) DIA. .25 45 ° X (.010) CHAMFER
.25 45 ° X (.010) CHAMFER
TOLERANCES EXCEPT AS NOTED: .127 .38 DECIMALS: .XXX ± .XX ± (.015) (.005), FRACTIONS: ± 1/64 ANGLE: ± 3 %
DIMENSIONS ARE: Specifications are subject to change without notice. Customers should verify actual device performance in their specific applications.
MM (INCHES)
3851/3852/3856 - 3/4 ” Diameter Panel Control
How To Order
3852 A 28 2 103 A L
12 16 16 20
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 Consult factory for lengths not shown.
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
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
APPLICABLE MODELS 3851, 3852, 3856 3851, 3852 3851, 3852 3851, 3852 3856 (3.18 mm D Shaft)
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
RoHS IDENTIFIER L Compliant Blank Non-Compliant
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
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
Boldface features are Bourns standard options. All others are available with higher minimum order quantities.
A B C D E F G H
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.
