Rotary Switch Basics

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Rotary Switch Basics Using Rotary Switches in
Your Design
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Electroswitch Rotary Switches

• Electroswitch offers many varieties of rotary
  switches for different application requirements.
  Electroswitch has acquired rotary switch lines
  from Stackpole, Shallcross, ASM, CRL / Centralab
  and Oak Grigsby.

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Rotary Switch Design Considerations Common
Specifications

• How many poles?
• Open or enclosed Frame switch?
• Changing Torque or Actuation Feel?
• Contact Material Advantages?
• Sealing Requirements?
• Size requirements or limitations?
• How many positions?
• Mounting Style
• PCB or panel mount?

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What is a Pole?

• A pole is the input or common terminal. It is an
  electrically isolated switching circuit.

Rotating Contact
Output Terminals
Common Pole
The rotating contact will channel the signal
from the pole to the output terminals. The
number of output terminals required determines
how many positions a switch will have.
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What is a Section?

• A section is also referred to as the deck, wafer
  or module.

sections
Sections are made up of the common and position
terminals of the switch. Switches can be made of
several sections to obtain multiple poles.
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Poles vs Section
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What is the difference between enclosed and open
frame?

• In open frame switches the moving parts are
  visible. The enclosed frame switches the parts
  are not visible.
• Open Frame switches have more flexibility on
  custom contact configurations
• Open Frame have a bifurcated wiping or self
  cleaning contact system ensuring reliable
  operation.
• Open Frame switches can have sections sold
  separately
• Enclosed Frame offers more protection from dust
  and contamination
• Enclosed frame switches are generally less
  expensive
• Enclosed frame switches are generally more compact

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Can you change the "Feel" or Torque of the switch?

• Yes. Changing the spring or number of springs in
  many switches will create a lighter or heavier
  detent actuation feel.

spring
This is done during the manufacturing process at
Electroswitch.
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When Should You Specify Gold Contacts?

• Gold plated contacts should be used when your
  product needs a longer shelf life.
• Also, if the switch will not be actuated for a
  long period of time after installation you may
  want gold contacts.

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What is the difference between Current Carrying
Capacity Current / Voltage Rating?

• Current carrying capacity, measured in amps, is
  the maximum load that a switch will carry with
  the contacts in a closed position.
• Current / voltage rating is the tested amperage
  and voltage capacity when switching contact
  positions under load (with current). An
  electrical arc occurs when switching between
  positions under load. Over a period of time, this
  arc may cause contact wear.
• A switch with the contacts closed has no arc, and
  the carrying capacity is higher.

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What is the difference between Shorting
Non-shorting contacts?

• Non-shorting contacts break before
  make
• (narrower contact)
• Shorting contacts make before break
• (wider contact)

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Different Stop Types

• A stop limits the rotation of the switch to the
  desired number of positions.
• Fixed Stop
• Stops are built into the switch at the factory
• Better for volume production requirements so
  customer does not have to adjust each switch
• These stops are not changeable by the customer
• Adjustable Stop
• Stop type where customer can adjust switch to
  desired number of positions
• Standard switches are supplied with adjustable
  stops preset at 2 positions
• Good Choice for low volume requirements
• Continuous Rotation
• Switch with no stops

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Adjustable Stop Mechanisms
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Can Electroswitch rotary switches be water
resistant sealed?

• Yes. Most Switch series offer a shaft and panel
  seal option. This allows the switch to be front
  panel sealed.

In addition, our C series switches have the
option to be completely sealed to meet an IP67
(submersion) rating.
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Applications

• Test and Measurement
• Pro and High end Audio
• Military and Aerospace
• Construction and Agricultural Equipment
• Medical and Diagnostic Equipment
• Transportation and Off Road Vehicles
• Military and Commercial Communication

Rotary switches can be used in many applications.
A rotary switch offers an easy way to switch more
combinations than what is offered by other
switches. It also offers the user a definite
tactile feedback for position location. Rotary
switches are generally more robust than other
types of switches or potentiometers.
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Rotary Switch FeaturesChoosing the Right Switch
for Your Design
Many available options Sealing to Meet IP67
The Electroswitch C series is an ideal choice for
enclosed switch requirements. The C series is an
economical option for lower current rotary switch
needs. It is ideal for requirements that need a
low profile compact switch. The C series has many
available options including BCD or binary coded
decimal outputs, water resistant sealing, push to
turn and dual concentric shaft designs.
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Enclosed TO5 Series

• Low Cost
• Smallest Switch, Only 362 in diameter
• Options include a boot seal which prohibits
• contamination of contacts during cleaning.

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Rotary Switch FeaturesChoosing the Right Switch
for Your Design
Many available options D1, D3 and D4 made to Mil
Spec
The Electroswitch D series is the ideal choice
for open frame switch requirements. This series
has lots of design flexibility. The D series has
many available options including water resistant
sealing and dual concentric shaft options. The
Electroswitch D1, D3 and D4 were originally
designed to meet Mil Spec requirements.
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Rotary Switch FeaturesChoosing the Right Switch
for Your Design
T-Slug Terminals and Tri Concentric Shafts
Electroswitch has recently added several open
frame series. These switches have unique
features that include Unidex housing, T-Slug
terminals, tri-concentric shafts, and uncommon
index angles. Several of the series also meet
Mil spec requirements and have water resistant
sealing options.
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Unidex Housing (A and F series)

• Utilizing dual ball detent indexing on a rugged
  star wheel. This detent offers 100,000 cycles of
  mechanical life, with the torque remaining
  constant and crisp throughout the life of the
  switch.

Unidex Housing
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T Slug Terminals(SK, 7M 4M Series)

• Wedgelock method of clip assembly
• Stronger, Longer Life Switch
• Patented "T" slug design eliminates rotation and
  twisting of contacts

Stator
Electroswitch T Slug Terminals for added
strength
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Tri-Concentric Shafts For Multiple Functions(7M,
LK and RK Series)

• This assembly may consist of three switches in
  one frame or two switches a potentiometer
  within the same frame limitations as a single
  shaft switch

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Rotary Switch FeaturesChoosing the Right Switch
for Your Design
Standard Switches for Spring-Return, High
Current, 24 Position PC mount
The Electroswitch E series has standard options
for special requirements. The E5 series is
designed to meet the needs of a 24 position pc
mount switch. The E3 series is a standard
spring-return rotary switch. The E4 series has a
current rating to switch 11 Amps _at_ 28VDC.
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Rotary Switch FeaturesChoosing the Right Switch
for Your Design
M6 and M7 can go up to 32 and 48 positions
The Electroswitch M series were originally
designed to meet Mil Spec requirements. These
switches are used in a variety of military,
avionic and industrial applications. The M6 and
M7 have the capability to go up to 32 and 48
positions.
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Value-Added Options

• Special readouts (BDC or other)
• Made Specific to Drawing
• Special Testing / Ratings Required
• Overmolding
• Key Lock
• Cable Harness
• Sealing (to IP67)
• Special Grease (Temp or Life)
• Knurled Shaft
• Push to Turn Shaft
• Dual Concentric Shafts

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