Features
■ RoHS compliant*
■ CW or CCW rotary switch
■ Linear and audio tapers
■ PC board and bushing mount
■ Splash seal
■ Metal bushing and shaft
Applications
■ Test and measurement equipment
■ Avionics controls
■ Communications equipment
■ Medical laboratory equipment
56 - Sealed 1/2 ” (12.5 mm) Panel Control w/Rotary Switch
*RoHS Directive 2002/95/EC Jan 27, 2003 including Annex.
Specifi cations are subject to change without notice.
Customers should verify actual device performance in their specifi c applications.
Electrical Characteristics1
Standard Resistance Range
Linear ......................................................................................................................................................................................................1K to 500K ohms
Audio .......................................................................................................................................................................................................1K to 500K ohms
Total Resistance Tolerance
B & D Tapers ............................................................................................................................................................................................................±20 %
E & S Tapers .............................................................................................................................................................................................................±10 %
Independent Linearity .......................................................................................................................................................................................................±5 %
Absolute Minimum Resistance ..................................................................................................................................................................... 2 ohms maximum
Effective Electrical Angle ............................................................................................................................................................................................. 240 ° ±5
Contact Resistance Variation ...........................................................................................................................................................................................±2 %
Dielectric Withstanding Voltage (MIL-STD-202, Method 301)
Sea Level ............................................................................................................................................................................................1,500 VAC minimum
70,000 ...................................................................................................................................................................................................500 VAC minimum
Insulation Resistance ......................................................................................................................................................................1,000 megohms minimum
Power Rating At 70 °C (Derate To 0 At 125 °C)
(Voltage Limited By Power Dissipation or 350 VAC, Whichever Is Less)
Linear Tapers ..........................................................................................................................................................................................................0.5 watt
Audio Tapers ........................................................................................................................................................................................................0.25 watt
Theoretical Resolution .................................................................................................................................................................................. Essentially infi nite
Environmental Characteristics1
Operating Temperature Range ...................................................................................................................................................................... +1 °C to +125 °C
Storage Temperature Range ........................................................................................................................................................................-55 °C to +125 °C
Temperature Coeffi cient Over Storage Temperature Range ............................................................................................................................±1,000 ppm/°C
Vibration ..............................................................................................................................................................................................................................8 G
Total Resistance Shift ................................................................................................................................................................................ ±2 % maximum
Voltage Ratio Shift ..................................................................................................................................................................................... ±5 % maximum
Shock ................................................................................................................................................................................................................................ 20 G
Total Resistance Shift ................................................................................................................................................................................ +2 % maximum
Voltage Ratio Shift ..................................................................................................................................................................................... ±5 % maximum
Load Life .................................................................................................................................................................................................................1,000 hours
Total Resistance Shift ...................................................................................................................................................................... ±10 % TRS maximum
Rotational Life (No Load) .....................................................................................................................................................................................50,000 cycles
Total Resistance Shift ...................................................................................................................................................................... ±10 % TRS maximum
Contact Resistance Variation ..................................................................................................................................................................................... ±2 %
Moisture Resistance (MIL-STD-202, Method 103, Condition B)
B & E Taper....................................................................................................................................................................................................... ±10 % TRS
D & S Taper ...................................................................................................................................................................................................... ±20 % TRS
IP Rating
Entire Unit ................................................................................................................................................................................................................... IP 64
Shaft/Bushing............................................................................................................................................................................................................. IP 65
Mechanical Characteristics
Stop Strength ............................................................................................................................................................................................... 56 N-cm (5 lb.-in.)
Mechanical Angle ...................................................................................................................................................................................................... 290 ° ±5 °
Torque
Running/Starting ........................................................................................................................................................0.2 to 1.3 N-cm (0.25 to 2.0 oz.-in.)
Mounting (Torque on Bushing) ..........................................................................................................................1.7 to 2.0 N-m (15 to 18 lb.-in.) maximum
Weight ....................................................................................................................................................................................................................... 8.5 grams
Terminals ........................................................................................................................................................................................................................ PC pin
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 fl ux.
Part can be wave soldered at 260 °C (500 °F) for 5 seconds, no wash process with no clean fl ux.
Marking .................................................................................................................. Manufacturer’s trademark, part number, resistance value and date code.
Ganging (Multiple Section Potentiometers) .................................................................................... Inquire for availability, minimum order quantity and price.
Hardware ...........................................................................................................One lockwasher and one mounting nut is shipped with each potentiometer.
1At room ambient: +25 °C nominal and 50 % relative humidity nominal, except as noted.
*RoHS COMPLIANT
56 - Sealed 1/2 ” (12.5 mm) Panel Control w/Rotary Switch
Initial Electrical Characteristics - Switch
Switch Type ......................................................................................................................................................................SPDT (Break before make)
Power Rating (Resistive Load) ..........................................................................................................................................................0.5 A @ 30 VDC
Dielectric Withstanding Voltage (MIL-STD-202, Method 301)
Sea Level ................................................................................................................................................................................. 1000 VAC minimum
Insulation Resistance ........................................................................................................................................................ 1000 megohms minimum
Contact Resistance ............................................................................................................................................................... 30 milliohms maximum
Contact Bounce ................................................................................................................................................................. 5 milliseconds maximum
Actuation Angle ................................................................................................................................................................................... 35 ° maximum
Switch Travel ....................................................................................................................................................................................... 25 ° maximum
Detent Torque ...............................................................................................................................................................1.3 N-cm (2.0 oz.-in) nominal
Environmental Characteristics1
Vibration ............................................................................................................................................................................................................... 8 G
Contact Resistance ............................................................................................................................................................ 30 milliohms maximum
Contact Bounce ............................................................................................................................................................ 0.1 milliseconds maximum
Shock ................................................................................................................................................................................................................. 20 G
Contact Resistance ............................................................................................................................................................ 30 milliohms maximum
Contact Bounce ............................................................................................................................................................ 0.1 milliseconds maximum
Rotational Life @ Rated Power .............................................................................................................................................................50,000 cycles
Contact Resistance .......................................................................................................................................................... 100 milliohms maximum
Moisture Resistance (MIL-STD-202, Method 103, Condition B)
Contact Resistance ............................................................................................................................................................ 30 milliohms maximum
Insulation Resistance (After 24 Hours @ Room Temperature - 500 VDC) ........................................................................ 100 megohms minimum
1At room ambient: +25 °C nominal and 50 % relative humidity nominal, except as noted.
Specifi cations are subject to change without notice.
Customers should verify actual device performance in their specifi c applications.
SHAFT FLAT ORIENTATION
PACKAGE DIMENSIONS W/PCB MOUNTING BRACKET
13CW
CCW
2
ANTI-ROTATION LUG (Style "A", 90 ° CW Shown)
0.41
(.016)
BUSHING DIAMETER
0.80
( .031)
2.20
(.087)
FOR TOLERANCES SHOWN: .XX = ± (.010)
.XXX = ±
(.005)
SHAFT DIMENSIONS ±
(1/32)
5.70
(.224)
6.20
(.244)
BUSHING DIAMETER
0.80
( .031)
2.77
(.109)
6.35
(.250)
The Model 56 can be used with either
of the two panel layouts shown.
(Double Module Front and Rear Bracket Shown)
16.51 ± 0.25
(.650 ± .010) 8.89 ± 0.18
(.350 ± .007)
.64
( .025)
"L"
0.30
(.0118)
5.08 ± 0.30
(.200 ± .012)
7.62 ± 0.30
(.300 ± .012)
12.5
(.492)
11.00
(.432) DIA.
0.74
(.029)
6.25
(.246)
7.00
(.275)
6.35 ± 0.25
(.250 ± .010)
.66 ± .05
(.026 ± .002)
3 X
2.54
(.100)
2.54
(.100)
16.51 ± 0.25
(.650 ± .010) .64
( .025)
"L"±
5.08 ± 0.30
(.200 ± .012)
0.91 ± .051
(.036 ± .002)
6.35 ± 0.25
(.250 ± .010) 7.62 ± 0.30
(.300 ± .012)
1.32 ± 0.25
(.052 ± .010)
12.5
(.492)
11.00
(.432) DIA.
0.74
(.029)
6.25
(.246)
7.00
(.275)
6.35 ± 0.25
(.250 ± .010)
.41 ± .05
( .016 ± .002)
2 X
2 X
5.08
(.200)
2.54
(.100)
5.08
(.200)
0.80 ± 0.30
(.031 ± .012) 1.52
(.060)
.25
.13
.80
( .100)TERMINAL SPACING
2.54
132 ° ± 5 ° CCW END
1.32
(.052)
FMS
C
LOF POT
2.54
(.100)
TYP.
1.27
(.050)
DIA.
4 PLCS.
1.02
(.040)
DIA.
6 PLCS.
6.35
(.250)
7.62
(.300) 5.08
(.200)
2’
2’
SPDT
1’
3’
CCW
CW
3’
1’ 12
3
Specifi cations are subject to change without notice.
Customers should verify actual device performance in their specifi c applications.
56 - Sealed 1/2 ” (12.5 mm) Panel Control w/Rotary Switch
Product Dimensions
DIMENSIONS: MM
(INCHES)
Recommended PCB Layout
Suggested Panel Layouts
Electrical Schematic
Switch Confi guration
Terminal Layout
OPT.
3/8-32UNEF-2A
9.53
(.375) 1.60 ± 0.25
(.063 ± .010)
OPT.
1.194 ± 0.10
(.047 ± .004)
SHAFT
6.35
(.250) BUSHING
9.53
(.375)
Specifi cations are subject to change without notice.
Customers should verify actual device performance in their specifi c applications.
56 - Sealed 1/2 ” (12.5 mm) Panel Control w/Rotary Switch
STD. LENGTH ‘L’
.750 (19.05)
.875 (22.23)
A Style Bushing
C Style Bushing
A Style Bushing -
Flatted Shaft
DIMENSIONS: MM
(INCHES)
How To Order
08/11
56 A A D - C 28 - B 15 / R81 L
MODEL
Code
56
Description
PC Terminals w/Rotary
Switch
BUSHING DESIGNATOR
Code
A
C
Description
3/8 ” D x 3/8 ” L Threaded
1/4 ” D x 1/4 ” L Threaded
SWITCH OPTION
Code
R80
R81
Description
SPDT CW
SPDT CCW
SHAFT LENGTH DESIGNATOR
Code
24
28
Description
3/4 “ FMS Long
7/8 ” FMS Long
RESISTANCE CODES
Code
10
13
15
18
20
22
23
Value in Ohms
1K
5K
10K
50K
100K
250K
500K
ELEMENT TAPER
TYPE/TOLERANCE
Code
B
E
D
S
Description
Linear CP ±20 %
Linear CP ±10 %
CW Audio CP ±20 %
CW Audio CP ±10 %
ANTI-ROTATION LUG /
BRACKET OPTION
Code
A
D
L
N
Description
AR Lug 90 °CW
No AR Lug or Bracket
Front Bracket
Front and Rear Bracket
NO. OF SECTIONS
Code
A
Description
Single plus Switch
RoHS IDENTIFIER
Description
Compliant
Code
L
Boldface features are Bourns
standard options. All others are
available with higher minimum
order quantities.
AVAILABLE ONLY WITH
SHAFT STYLE BUSHING
Code Description Code
B 1/4 ” D Slotted End A
C 1/4 ” D Flatted End A
E 1/8 ” D Slotted End C
Shaft/Bushing Styles
1/4-32UNEF-2A
OPT.
6.35
(.250) 0.79 ± 0.25
(.031 ± .010)
OPT.
0.79 ± 0.10
(.031 ± .004)
SHAFT
3.18
(.125) BUSHING
6.35
(.250)
3/8-32UNEF-2A
OPT.
9.53
(.375) 1.52 ± 0.25
(.060 ± .010)
OPT.
5.49 ± 0.10
(.216 ± .005)
SHAFT
6.35
(.250) BUSHING
9.53
(.375)
MAX. FLAT LENGTH 15.88
(.625)
Asia-Pacifi c: Tel: +886-2 2562-4117 • Fax: +886-2 2562-4116
Europe: Tel: +41-41 768 5555 • Fax: +41-41 768 5510
The Americas: Tel: +1-951 781-5500 • Fax: +1-951 781-5700
www.bourns.com
STD. LENGTH ‘L’
.750 (19.05)
.875 (22.23)
STD. LENGTH ‘L’
.750 (19.05)
.875 (22.23)
