Hello friends welcome to the new post. In this post, we will have a look at Double Pole Single Throw Switch. If you are an electrical engineer and love electrical, then you must have knowledge of different types of switches used in different circuits. The very commonly used switch is the double pole single throw switch, which is also called the DPST switch. It is mostly used in different electrical devices since it controls the current flow effectively. In this post, we will cover the different parameters of this switch like working, construction, and uses. So let’s get started DPST switch.
What is a Double Pole Single Throw Switch?
- The double pole single-through switch is used to current flow. It has two different inputs and two different output points hat are connected with different components of circuits
- DPST switches come with two conditions ON and OFF that used for control the power of circuitry
Construction of DPST Switch
- The DPST switch is made with the use of two poles that are attached with two distinct input and output points. Poles are made of conductors like copper and insulated from plastic which is a non-conducting material.
- The button of the level is used to operate switches that are connected with poles through the use of mechanical linkage. If the switch is in ON two poles connected help current to flow from the switch
- In off condition poles are disconnected and no current flow in circuit
Working Principle of DPST Switch
- The working principle of the DPST switch is simple and easy. The switch is made to break or connect the circuit connection with two poles and the OFF and ON states control current flow. If the switch is in an ON state two poles are connected and the current passes
- In the OFF state, poles are not connected and the current flow is zero.
Types of DPST Switch
- There are two main types of DPST switches that are commonly used in circuits
- Toggle DPST Switch: It is a switch type that functions with a toggle or level that changes the switch to an ON and OFF state
- Rocker DPST Switch: This switch works with the use of a rocker or button that is pressed to switch circuitry OFF and ON
Advantages of DPST Switch
- It can control the current flow very easily and simple way.
- They are durable and structured and handle a larger current
- Their installation and maintenance are easy
- It used in different circuits and appliances
Disadvantages of DPST Switch
- It needs a larger space to install than other switches
- They are more costly than other switches
- It can only be used to flow current in one circuitry
Applications of DPST Switch
DPST switches main application are explained here
- It is used to control the different industrial machines and motors
- It is used to turn off and ON lights in homes and offices
- It is used to switch between two audio sources in the sound system
- It controls the current in battery charging circuits
- Work as safety switches in heavy machines
- It controls the switching process in different power sources in a circuit.
- It is used to control the heating element in the water heater
- It controls the oven temperature
- DPST switch to control the current in different electronic devices like computers, TV and other appliances.
Difference Between, SPST, SPDT and DPDT
|Number of Poles
|Number of Throws
|Single Pole Single Throw
|single circuit contrl
|Single Pole Double Throw
|Controls a single circuit to be configured with one of two other circuits
|Double Pole Double Throw
|it regulates two independent circuits to be connected to one of two other circuits
DPST vs SPST Switch
- DPST switch is compared with single pole single through switches called SPST switch. The main difference between the two switches is that DPST has two poles and SPST has one pole. It means that the DPST switch has the ability to control the current flow in two circuits and the SPST controls the current in one circuitry
|it comes with two poles
|This switch has one pole
|It can control the current in two switches
|It can control current in one circuitry
|It is used in different appliances like motors and machines for their power supply control, turning on and off lights and fans, controlling the heating element in a water heater switching between multiple power sources,
|It is used in simple on or off applications like on and off the light or Fan
DPST vs DPDT Switch
The DPST switch is also compared to the double pole double throw switch, also known as the DPDT switch. The main difference between the two switches is that the DPST switch has two positions, while the DPDT switch has three positions. This means that the DPDT switch can control the flow of electricity in three circuits, while the DPST switch can control the flow of electricity in only two circuits.
|Number of poles
|Number of throws
|Number of circuits controlled
|Can switch each circuit to two destinations
|Can switch two circuits to one destination
|Can select a signal from multiple sources
Read our latest Electronic Guides:
How to wire a Single Pole Double Throw (SPDT) switch.
Gather Materials and Tools
Before starting the wiring process, there is need for some instruments that are listed here
- Single pole double throw switch
- Wire strippers
- Electrical tape
- Electrical wire
Understand the Switch Connections
- As discussed above SPDT switch has 3 terminals COM, NO, and NC terminals. The COM terminals are used middle terminal and NO and NC are on the other sides.
- First of all, off the power supply of the circuit where the switch has to connect
- Strip the wire ends that we are going to use to wire the switch
- With the use of a screwdriver connect one point of wire with the COM terminal of the switch
- The other end of the wire connects with the power supply circuit
- Connect 2nd wire with the NO terminal of the switch through the screwdriver
- Attach another end of 2nd wire to load that we have to control
- Connect 3rd wire to the NC terminals of a switch with the use of a screwdriver
- Connect the other end of 3rd wire with the ground or neutral wire in the circuitry
- When all connections are completed wrap the tape around the connections to make insulation and avoid the short circuits
- At last on the power supply and test the switch to make sure that it is working accurately
Safety Precautions while Working with DPST Switch
- Off power supply till the end of the connection process
- Instruments used to be accurately configured and isolated
- Wear gloves and glasses before starting work
- Follow teh wiring diagram to avoid any fault
- The current provided to switch must be according to limited value
How Does an SPDT Switch Work?
- The SPDT switch comes with three terminals or connections that are common terminal, COM, normally open or NO and normally closed terminal. When the switch is in off-state circuit is attached to the NC terminal and when the switch is in ON state circuit is attached to the normal open circuit. The COM point is always attached to either NO or NC point on the base of the switch position
Uses of SPDT Switches
SPDT switches main uses are explained here
- In lighting circuits, this switch is used to control light with two different switches like at the top and lower side of the staircase
- In electronic circuits, SPDT is used between two input sources like a mixer or amplifier.
- In automotive circuits, it is used to switch different modes of operation like low and high beams on the headlight
What is Single Pole vs Double Throw?
|Number of Connections
|2 (1 input, 1 output)
|3 (1 input, 2 outputs)
|Number of Positions
|2 (on/on or off/on)
|Controls one circuit
|control two circuits
|Lighting, fans, outlets
|Reversing motor direction, selecting between two power sources
Advantages of SPDT Switches
The advantages of SPDT switches are explained here
- Versatile nature: These switches are used in circuits that are controlled between two outputs
- Simplicity: The design of this switch is simple and easy to configure
- Durability: They are created with high-quality materials that can withstand hard conditions
Spdt Switch Diagram
- In the circuit diagram, the switch is off-state. The circuitry is connected with a normally closed NC point which means that the circuit is not completed and zero current flowing. When the switch is at on state. the circuit is connected to the normally open terminal that makes the circuit complete and helps the current flow.
- The common terminal is always attached to either the NO or NC terminal on the base of the position switch
What is an example of a Single Pole Double Throw switch?
- An example of a single pole double through the switch is a light switch that controls lights in the room with two different points. This switch is known three qat switch since it needs three connections but it is a single pole double through the switch
- In three-way switch circuitry one switch is located at the top of the stairs and the other at one at the bottom. When the switch at the top stairs flipped to on state. It completed the circuitry and ON the light. When switching at the bottom of the stairs to on state. it breaks the circuitry at the top switch and completes the circuit at the bottom switch and the light is oN
- The single pole double through a switch in this condition is the main component of both three-way switches and helpings circuit to be complete at any switch but not at both switches simultaneously.
Write the maximum current rating of a DPST switch.
- The maximum current rating of the DPST switch depends on the size and construction of the switch. Inrush’s current NC rating is 30A max and for NO 15 A maximum
Is the DPST switch control the flow of electricity in 2 circuits?
- Yes, it can control the current flow in two circuits like two separate switches
How to wire a DPST switch?
- For wiring, the Double pole single-through switch connects one input point with the power supply and another input terminal with the load. After that connect one output point to the power supply and the other output to the load
Write applications of DPST switches?
- These switches are used in different electrical appliances like power supply to motors and machines on and off. It also has on and off lights and fans, controlling the heating element in a water heater
- Is DPST switches be used as safety switches in heavy-duty machinery?
- Yes, it works as safety switches in heavy-duty machines since they are durable and have the ability to handle high current loads
The double pole single throw switch is part of different devices and circuits where current flows. it has two poles that help the control current flow in two different circuits. The switch is easy to maintain and install Wiring a DPST switch is a simple and easy process, but it must follow some safety precautions while working with it. Follow for more latest Electronics Information https://www.theengineeringknowledge.com/