The following post discusses the wiring connections for driving a DC motor in clockwise and anticlockwise directions with the help of a single toggle switch and a relay circuit. The idea was requested by one the interested followers of this blog. Let's learn more:
Technical Specifications
We have our project in school.
Our professor asks us to design a transistor together with a relay that allows a motor to rotate clockwise and then , a switch will be press , then will rotate counter-clockwise.
In other words a single switch should be able to control the reverse forward rotation of the motor.
Thanks in advance.
The Design
A DC motor can be very simply rotated both ways in clockwise as well as in anticlockwise directions by flipping the supply inputs to it.
However the above reversing requires flipping of both of its wire polarity with the connected supply.
Therefore it cannot be done by using a single relay or switch.
However by using a couple of relays, a single switch operation becomes feasible for toggling the connected DC motor in both reverse and forward directions.
The following circuit shows the wiring details of the relay with the motor which is controlled by a transistor driver stage.
On switching power ON, the motor starts rotating in either clockwise or anticlockwise direction depending upon the wire polarity of the motor.
When SW1 is pressed, the direction gets instantly reversed and continues until S1 is switched OFF.
Actually the transistor stage is not required here, the implementation could be done simply with the relays and SW1.
More simply, the whole reverse forward operation can be conducted using an ordinary single DPDT toggle switch.
Warren Orman says
I’m looking to buy a counter clockwise motor 60 rpm 110volt synchronous motor to turn a polarized disc but it needs to go in the counter clockwise position. What do I ask for and or buy from? Thanks,
Swagatam says
Sorry, we don’t sell assembled circuits.
Pavan says
pls guide which relay make use for clockwise and anticlockwise for single phase motor(230V).
its very urgent
Swagatam says
sorry, I am not sure how an AC motor may be rotated in both directions.
Kousik Singha says
Hii sir, please help me how i can make automatic rain sensing wiper motor control using 555 timer ic
Swagatam says
Hi Kousik, you can refer to the following article
https://www.homemade-circuits.com/2012/09/rain-triggered-instant-start-windshield.html
Swagatam says
it's for protecting the transistor from relay coil back EMF
MAnoj Cracked says
Can you please tell me where to connect those relays … I mean are they directly connected to 12v DC supply…??
Swagatam says
yes both the relay coils are connected between +12V and the transistor collector
Camilius says
Sorry, is there anyway to attend a short course for me to learn how to make a device that use both clockwise and unti-clockwise?
Swagatam says
The circuit explained above can be used to operate the motor in both clockwise and anti-clockwise directions.
Jordy Brusselman says
Ooh god you dont need to approve my previous message. I was on the wrong page. I thought I was on the buying page. Sorry for the trouble :p
Swagatam says
No problems!
Jordy Brusselman says
Hello i'm a real noob when it comes to electronics :p Can this motor go counterclockwise to iff I use a DPDT switch? I need a mini motor for a cosplay project so it can spin both clock and counterclockwise.
Michael Murray says
How to change rotation on my evaporator fan motor 12 volts dc 220ma three wire