How Can The Direction Of DC Motor Be Changed? (Change The Polarity In Two Ways)

The DC motor is designed in one direction. Sometimes, the motor direction must be changed for rotating machine purposes. However, some applications don’t require changing the direction of the DC motor because not all machines are made to be rotational. But if you need to change it, what can you do? How can the direction of the DC motor be changed? The direction of a DC motor can be changed in three methods. You can reverse the Armature supply polarity and field Winding polarity, or use a gearbox to change the direction of a DC motor.

However, in this article, I will cover a step-by-step guide on how you can change the direction of a DC motor, why it needs to be changed, how to wire a reverse polarity switch, etc. Please read till the end to find out more!

How Can The Direction Of DC Motor Be Changed?

The DC motor was wired in the wrong way or the direction of the current needs to be changed for certain rotational purposes. The reason can be anything. But when it comes to changing the direction, what to do? There are multiple methods of changing the direction of a DC motor. These methods can be used based on the application. Please check out the methods below to learn about it.

Reversing Armature Supply Polarity

1. Step: Locate the positive terminal of the Armature winding

2. Step: Locate the negative terminal of the Armature winding

3. Step: Connect one connection of the power source to the positive terminal

4. Step: Connect the other connection to the negative terminal

5. Step: Turn on the power circuit and check if the motor is spinning in the opposite direction

Reversing Field Winding Polarity

1. Step: Locate the positive and negative terminal of field winding. If field winding’s terminals are not accessible, then you need to connect the H-Bridge driver to prepare a separate circuit

2. Step: Now swap up the connections of the power source to the Field Winding’s polarity

3. Step: Check if the motor is working in the opposite direction

Using Gearbox

This method is not well-known. However, this device can change the DC motor rotation direction. It uses gears to change the DC motor direction. By using the combination of gears, it changes the flow of current.

Why does DC Motor Direction Need To Change?

Sometimes starting a DC motor faces some problems. Forward and reverse, motors need to change their direction. There are also a few reasons that I have discussed below. A DC motor is designed in a way that can only go in one direction and run the end application. But you might be curious to know why the DC motor direction needs to change when it is already specialized in one direction. So let’s clear all your doubts regarding this thing. Please check out below to know about it:

• The DC motor can be wired in the wrong position and cannot run applications that require only one direction current. In this case, the motor direction needs to be changed
• Some applications need to use the forward and backward direction of the DC motor. These applications can be robots, rotational machines, conveyor belts, etc. The one-direction DC motor cannot make these machines move forward or backward. That’s why the direction needs to be altered
• DC motor can be stopped fast in case you need to stop it quickly. That time changing the direction of the supply voltage will help the motor to stop fast

How To Change the Direction Of A Three-phase Motor?

The change of direction in a Three-phase motor is quite the same as in the one-phase induction motor. However, there are some differences in changing the DC direction. Let’s have a look at how you can change the direction of a three-phase DC motor:

1. Step: Locate the positive and negative terminals of the DC motor

2. Step: Swap up two of any three lines phase to the positive and negative terminal of the DC motor.

3. Step: You can use an H-bridge electrical circuit if needed

4. Step: Finally, test the DC motor by turning it on and check if it’s working in the right direction

How To Wire A Reverse Polarity Switch?

Whenever you want to change the DC motor direction by field windings, the circuit to swap polarity might be not accessible. You need to prepare the terminal by attaching a reverse polarity switch to it.

The wiring of this switch should be done properly. Here is a step-by-step guide on how you can wire a reverse polarity switch:

1. Step: Take two wire and insulated disconnected terminals. Cut off the edge of both wire

2. Step: Twist one of the half-cut wires together. Insert it into one disconnect terminal

3. Step: Add another disconnect terminal to one of the wires again

4. Step: Now take the second wire and twist it like the first one.

5. Step: Now attach two of the terminals with the pole

6. Step: Take another wire to connect it to the battery to give power. Attach it to the disconnect terminal

7. Step: Now take another wire to connect it to the ground connection
8
. Step: Then connect them to the center poles

9. Step: Finally, it is done!

Simple DC Motor Forward And Reverse Circuit With Diagram

The DC motor and supply are connected through a switch. This is a forward and reverse switch for the electric motor. The switch acts mainly to change the direction of the DC motor. The switch changes the polarity of the voltage. The timer IC gives output to the transistor. Now the output can be changed by using the VR1 resistor.

This is how speed control helps to change the direction of the DC motor. You can make a reverse forward DC motor by controlling the speed.

Pros And Cons Of Changing DC Motor Direction

It is necessary to change the DC motor direction because the motor could run in the wrong direction sometimes. There could be many more issues. But as changing the direction has advantages, it also has some disadvantages. Let’s have a look at the Pros and Cons of changing the DC Motor direction:

Pros

• Changing the DC motor direction is cost-effective
• It may provide a good fluid dynamic
• Enabling machine to move or rotate in a different direction

Cons

• Altering the DC motor direction may cause wear and tear in the DC motor components. It will reduce the life expectancy of the DC motor
• The control systems can be expensive to change the direction of the motor.

How To Change the Direction Of DC Motor Arduino?

A DC motor Arduino is a board that uses codes to control the DC motor speed and change its direction. But how you can change the direction using this way? Please check it out below

Setting up the Arduino

/*

Adafruit Arduino – Lesson 15. Bi-directional Motor

*/

int enablePin = 11;

int in1Pin = 10;

int in2Pin = 9;

int switchPin = 7;

int potPin = 0;

void setup()

{

pinMode(in1Pin, OUTPUT);

pinMode(in2Pin, OUTPUT);

pinMode(enablePin, OUTPUT);

pinMode(switchPin, INPUT_PULLUP);

}

void loop()

{

int speed = analogRead(potPin) / 4;

setMotor(speed, reverse);

}

void setMotor(int speed, boolean reverse)

{

analogWrite(enablePin, speed);

digitalWrite(in1Pin, ! reverse);

digitalWrite(in2Pin, reverse);

}

1. Step: Define the pin and mode in the setup function

2. Step: Then look out for the motor value in the potentiometer. Now divide the analog from the reading by 4

3. Step: Now if you press the button, it will run in the forward direction. If you do not press the button, it will run in the reverse direction. So if it’s reverse, it is set to “True” and if it’s forward, it will be set to “False”

Controlling The DC Motor Direction

void setMotor(int speed, boolean reverse)

{

analogWrite(enablePin, speed);

digitalWrite(in1Pin, ! reverse);

digitalWrite(in2Pin, reverse);

}

4.Step: Connect the pin to a motor driver

5. Step: Now set opposite values In1 and In2 pin

6. Step: If In1 is high and In2 is low, the motor will run in one direction. And if In1 is low and In2 is high, then the motor will run in the opposite direction

Precautions To Take Before Changing The DC Motor Direction

There can be some issues when changing the DC motor direction. It can hamper the DC motor and reduce its life expectancy. So, you should take precautions before changing the motor’s direction. Please check the considerations you must follow when changing the motor’s direction below:

• Sparking may occur when you swap the connections. In this case, you can use spark arrestors. It will protect the circuit from sparking
• As you change the DC motor’s direction, it may affect the motor’s speed. So you can use external digital systems to control the speed of the DC motor
• If you are constantly changing direction, you can consider using a switch to change directions

The readers have frequently asked questions regarding changing the direction of a DC motor. Please check out the answers below in case you have similar questions:

Q. Is DC Motor Current One Directional?

Yes. DC motors are one-directional. This is because the power can be supplied to the end application without any obstruction. It leads the machine to work properly.

Q. Is A DC Motor Better Than An AC Motor?

The performance of the AC motor and DC motor is based on their qualities. The AC motor is used for phones, transmissions, etc. On the other hand, the DC motor is used for electronic devices. Hence, both of the motors is efficient and good according to their performance delivery.

Q. How To Slow Down The Rotation Of A DC Motor?

There are multiple ways to slow down the rotation of a DC motor. Using gear, a belt drive system can slow down the rotation. Another way can be the PWM method, which works efficiently in slowing down the rotation of a DC motor.

Conclusion

The DC motor direction change is important for reversing the directions of rotational machines such as remote control players, belts, etc. The DC motor direction can be changed in different methods. Well, these methods can be applied to keep the application in mind.

Moreover, sometimes it’s only a wiring mistake that leads to a change in the wire. So you can change the DC motor direction using the suitable method. However, I hope this article helped you with how can the direction of DC motor be changed.