BOURNS 3851E121102BL

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V SC
AV ER OM
AI SIO PL
LA N IA
BL S NT
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*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.