Contact Resistance Variation ...........................±1 % .................................................................±3 % of total resistance or 3 ohms
(whichever is greater)
Dielectric Withstanding Voltage (MIL-STD-202, Method 301)
Total Resistance Shift ................................... ±10 % maximum ................................................ ±3 % maximum
Rotational Life (No Load) ................................... 100,000 cycles ................................................... 20,000 cycles
Total Resistance Shift ................................... ±15 % TRS maximum ....................................... ±5 % or 5 ohms TRS whichever is greater
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;
locking bushing versions are shipped with one additional locking nut
specifications tested at 250 RPM, at room ambient: +25 °C nominal.
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
3851/3852/3856 – 3/4 ˝ Diameter Panel Control
Product Dimensions
9.53
(.38)
.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
.047 WIDE X
1.60+.38/.00
DEEP
(.063+.015/-.000)
6.35
±
.76
(.25
±
.03)
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
6.35
±
.76
(.25
±
.03)
19.05
(.75)
DIA.
12.19
DIA.
(.480)
19.05
(.75)
DIA.
12.19
DIA.
(.48)
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
.72
THREE
(.028)
DIAMETER
14.02
±
.25
(.724 DIA. AWG
(.552
±
.010)
STRANDED) WIRES.
STANDARD
PRINTED CIRCUIT TERMINAL
1.02
6.35
TYP.
TYP.
(.040)
(.25)
15.88
±
.38
(.625
±
.015)
16.00
5.49
OPTIONAL FLAT
(.63)
(.216)
1.52
28.58
LONG OR
FRONT BUSHING FOR SHAFTS UNDER
(.06)
(1-1/8)
1
2
3
6.35
(.25)
6.35
(.25)
9.53, 22.23
STD.
(3/8, 7/8)
.38
(.015)
2.36
(.094)
1/4-32 UNEF
.25
45
°
X (.010)
CHAMFER
6.35
±
.76
(.25
±
.03)
9.53
(.38)
.38
(.015)
12.7
STD.
(1/2)
1/4-32 UNEF
.25
45
°
X (.010)
CHAMFER
6.35
±
.76
(.25
±
.03)
SUGGESTED BOARD LAYOUT
6.35
6.35
(.25)
(.25)
1.40
DIA.
(.055)
19.05
(.75)
DIA.
12.19
DIA.
(.480)
19.05
(.75)
DIA.
3.18
±
0.25
DIA.
(.125
±
.001)
3.18
±
.025
DIA.
(.125
±
.001)
SHAFT SLOT
.79 WIDE X .76 DEEP
(.031)
(.03)
.25
OPTIONAL FLAT
LONG OR
(.010)
1.52
15.88
FRONT BUSHING FOR SHAFTS UNDER
(.06)
(5/8)
SHAFT SLOT
.79 WIDE X .76 DEEP
(.03)
(.031)
12.19
DIA.
(.480)
A, B & H BUSHINGS
9.53
(.375)
C & E BUSHINGS
9.53
(.375)
9.91
DIA.
(.390)
3.18
DIA.
(.125)
3.18
6.73
DIA.
(.125)DIA.
(.265)
9.53
(.38)
6.35
±
.76
(.25
±
.03)
12.7
(.50)
.38
(.015)
6.35+.03/-.05
DIA.
(.250+.001/-.002)
3/8-32 UNEF
1.19
(.047)
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 SLOT
ALIGNMENT
AT CCW
FLAT
ALIGNMENT
AT CCW
50
° ±
10
°
50
° ±
10
°
19.05
(.75)
DIA.
12.19
DIA.
(.480)
1.60+3.81/-.000
(.063+.015/-.000)
DIA.
22.23
STD.
(7/8)
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
2.67
±
.381
(.105
±
.015)
ANTI-ROTATION LUG
PROJECTS 1/16 INCH
ABOVE MOUNTING FACE.
TOLERANCES EXCEPT AS NOTED:
.127
.XX
±
.38
DECIMALS: .XXX
±
(.005),
(.015)
FRACTIONS:
±
1/64
ANGLE:
±
3 %
.25
45
°
X (.010)
CHAMFER
DIMENSIONS:
MM
(INCHES)
CCW
1
3
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
POTENTIOMETER
2
3851/3852/3856 – 3/4 ˝ Diameter Panel Control
Hardware
LOCKWASHER H-37-1
6.6
(.26)
NUT H-38-1
9.53 +0/-0.38
(.375 +0/-.015)
2.36 ± 0.25
(.093 ± .01)
LOCKNUT H-38-3
4.57 ± 0.05
(.180 ± .002)
7.75
(.305)
11 +0/-0.43
(.433 +0/-.017)
NUT H-38-2
2.36 ± 0.25
(.093 ± .01)
30 ° ± 5 °
1.02
(.040)
30 ° ± 5 °
TYP.
0.64
(.025)
15 ° ± 1 °
1/4-32 UNEF
1/4-32
NEF-20
12.07 ± 0.25
(.475 ± .01)
LOCKWASHER H-37-2
9.58 ± 0.36
(.377 ± .014)
0.64 ± 0.05
(.025 ± .002)
7.92
(.312)
3/8-32 NEF-2B
3.96
(.156)
12.52 ± 0.36
(.493 ± .014)
0.56 ± 0.05
(.022 ± .002)
14.66 +0/-0.43
(.577 +0/-.017)
30 ° ± 5 °
Date Code Description
YYWWM
M = COUNTRY OF MANUFACTURE
(MEXICO)
WW = WEEK NUMBER
YY = LAST TWO DIGITS OF YEAR
MANUFACTURED
DIMENSIONS:
MM
(INCHES)
LOCKNUT H-38-4
8.51 ± 0.05
(.335 ± .002)
1.91
MIN.
(.075)
18 ° ± 2 °
3/8-32
NEF-2B
1.02
(.040)
12.7
(.5)
1.14 ± 0.38
(.045 ± .015)
30 ° ± 5 ° TYP.
4.83
(.19)
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
3851/3852/3856 – 3/4 ˝ Diameter Panel Control
How To Order
3852
A
-
28
2
-
103
A
L
12
16
16
20
28
28
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
7/8 ” (22.20 mm) L X 1/4 ” (6.35 mm) D
7/8 ” (22.20 mm) L X 1/8 ” (3.18 mm) D
AVAILABLE ONLY IN
MODELS
3851, 3852
3851, 3852
3851, 3852
3851, 3852
3851, 3852
3856
3851, 3852
3856
BUSHINGS
C
A
C, E
A, B
A, B
A
C, E
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
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
ELEMENT
TAPER/TOLERANCE
A
Linear ±10 %
B
Linear ±20 %
C
Audio CW ±10 %
D
Audio CW ±20 %
E
Linear ±10 %
F
Audio CCW ±10 %
G
Audio CCW ±20 %
H
Linear ±5 %
RoHS IDENTIFIER
L
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.
APPLICABLE
MODELS
3852, 3856
3851
3852, 3856
3851
3851
3852, 3856
3851
3852, 3856
Asia-Pacific:
Tel: +886-2 2562-4117 • Email: asiacus@bourns.com
EMEA:
Tel: +36 88 885 877 • Email: eurocus@bourns.com
The Americas:
Tel: +1-951 781-5500 • Email: americus@bourns.com
www.bourns.com
REV. 10/20
Specifications are subject to change without notice.
Users should verify actual device performance in their specific applications.
The products described herein and this document are subject to specific legal disclaimers as set forth on the last page of this document, and at www.bourns.com/docs/legal/disclaimer.pdf.
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