Rotary switches applications and uses are diverse with industrial companies buying rotary switches because they are known for having better pole and throw abilities when compared to other types of switches. Pole and throw capabilities determine the functionality of the rotary switch. The angle of throw is expressed by the number of positions, while the number of poles indicates the amount of circuits controlled by the rotary switch.

Rotary switches are used for devices with two or more channels or operational modes and can be found in navigation and communication systems, sound mixing and editing equipment, radios, transmitters and receivers. If you are in the business of repairing or manufacturing devices with two or more operational modes, it’s important that you learn about the various rotary switches applications and uses. You should:

1. Determine best practices for using single deck or multideck rotary switches.

2. Evaluate the benefits of rotary limit switches.

3. Rely on electric rotary switches for your shaft-based machinery needs.

Action Steps
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Choose appropriate uses of single and rotary multideck switches

Single deck rotary switches come in a range of configurations to meet your budgetary, security and performance needs. For example, single deck rotary switches can be manufactured to require keys to provide enhanced security for your device. A key lock single deck rotary switch is frequently used for its high security by businesses in aircraft, weapons, medical and industrial industries. Multideck rotary switches have less post panel depth than rotary single deck switches, which makes rotary multideck switches easier to replace and switch out than a rotary single deck switch.

I recommend: Find out more about key lock single deck and rotary multideck switches at Cole Instrument. You may also visit Grayhill to obtain information about rotary single deck switch uses.

Buy rotary limit switches to meet sophisticated technology needs

Rotary limit switches allow multi-pole and position circuits. They are uniquely designed to transform a mechanical motion to an electrical signal. The mechanical motion is typically in the form of a rotary cam which is a rotary switch component used to break or initiate electrical contact inside the rotary switch. A rotary limit switch can be used in a variety of devices including electrically operated conveyor belts, doors and work tables.

I recommend: Read more about rotary limit switches at Gleason Reel. Find out about rotary limit switches for screw jacks at Nook Industries.

Consider using cam rotary switches for shaft-based devices

The mechanical motion of rotary limit switches is typically in the form of a rotary cam which is a rotary switch component used to break or initiate electrical contact inside the rotary switch. Cam rotary switches are ideal for shaft-based devices that undergo minimal changes after the initial set up. They can be used to control devices such as mechanical relays, solenoids, glue guns and other similar components.

I recommend: Check out Electro Cam for more information about rotary switches. You can also learn more about cam rotary switches by visiting J.R. Merritt Controls.

Rotary switches allow switching from one mode to another in an electrical device or system. Common examples familiar to all are CB radio frequency rotary switches and those on three-speed fans. However, there are also industrial rotary switches for machinery control, as well as rotary switches for thousands of other devices in aircraft, hospitals, businesses and homes.

Most rotary switches consist of a knob and an actuator with several layers of contacts for multiple poles. There are actuator alternatives, like a bare shaft or a key hole. There are several important specifications to compare between rotary switches:

1. Number of positions is also referred to as angle of throw. For example, a 5-position switch will have a 72-degree angle of throw (360/5).

2. Number of poles indicates the number of separate circuits the rotary switch will control.

3. Rotational life is an indicator of the durability of a rotary switch.

4. Number of decks a switch will accommodate.

Action Steps
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Buy rotary switches that fit your applications

Find a switch that matches the number of poles and decks suitable for your application. Single deck rotary switches are common, but there are also rotary multideck switches. Also, find a switch body that will fit the space and has a handle or actuation style that works well for you. You may even wish to pay attention to details like how the actuator stays in position. Some rotary switches have detents, while others come with potentiometers.

I recommend: Digi-Key has a wide range of rotary switches to choose from and a helpful part search tool to help you select the right model. You can also find more specialized sources of rotary switches, like Micronor, which carries a good selection of rotary limit switches.

Know the difference between shorting and non-shorting rotary switches

Shorting, otherwise known as make-before-break, rotary switches prevent any arcing that could occur while switching between positions. The alternative is the non-shorting rotary switch, which is referred to as break-before-make. As the name implies, this type of switch opens (turns off) the previously selected circuit before it opens (turns on) a new one.

I recommend: If you look at the wide selection of rotary switches at Surplus Sales of Nebraska, you will find examples of shorting rotary switches for sale. For an example of a non-shorting rotary switch, check out the four-pole, three-position model available from Ace Electronics.

Seek out a specialty or custom electric rotary switch

There are enough ready-made rotary switches to cover most applications. However, some specialized equipment requires special made switches.

I recommend: Digitran manufactures extremely low-profile switches for military and aerospace applications. Their stock includes rotary switches and they produce custom rotary switches. Additionally, Shallco is a great all-around source for custom rotary switches, from general use to military applications.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  For added safety, buy a rotary switch that has a guarded position selection. Push, pull or otherwise manipulate these knobs to switch position. For security and restricted access, there are even keyed actuators.