How to Run a 12V DC Motor on 120V AC [Step-by-Step Guide]

Automotive, industrial, and consumer goods are just a few of the industries that frequently use 12V DC motors. Since the voltage levels are incompatible, running a 12V DC motor on 120V AC is impossible. While 120V AC is a high-voltage alternating current, a 12V DC motor is made to run on a 12V direct current. 

However, a switching power supply can be used to run a 12V DC motor on 120V AC. In order to transform the high-voltage AC input into the lower-voltage DC output required to run the motor, the switching power supply is essential. In this article, we’ll briefly discuss the methods and considerations for running a 12V DC motor on 120V AC.

Essentials and Procedure to Run a 12V DC Motor on 120V AC

Yes, you can run a 12V DC motor on 120V AC. The materials you’ll need to build the circuit-

• Switching power supply that converts 120V AC to 12V DC and has a current rating high enough to run your motor
• 12V DC motor 
• Diode (for protection against reverse voltage)
• Capacitor for adjusting voltage (Optional)
• Connectors and wiring
• If the motor or power supply produces a lot of heat, a heat sink

Fig. 2: Block diagram of the process

Understanding the specifications and constraints of both the motor and the power supply is crucial since changing the voltage may also have an impact on the performance of the motor. Here are the steps on how to run the process.

Step 1: Choose a Switching Power Supply

You should take into account the following criteria when selecting a switching power supply to operate a 12V DC motor on 120V AC:

Current Rating

The switching power supply needs to have a current rating that is at least as high as the current your motor will use. The nameplate of your motor will have the current rating. Typically, the current rating is expressed in amps (A).

Voltage Rating

The switching power supply must be rated for 12V DC output in terms of voltage. This indicates that a voltage of 12 volts will be generated between its positive and negative terminals.

Efficiency

The switching power supply needs to be highly rated for efficiency. This indicates that the majority of the power coming from the wall outlet will be converted into DC power for your motor. 

Ratings of efficiency are frequently presented as percentages. For instance, a switching power supply with a 90% efficiency rating will enable your motor to run on 90% of the power coming from the wall socket. Heat loss will account for the remaining 10% of the power.

Ripple Voltage

Low ripple voltage should be a requirement for the switching power supply. A tiny AC voltage called ripple voltage is superimposed on the switching power supply’s DC output. 

The motor controller in your motor is one sensitive electrical component that might be harmed by ripple voltage. Millivolts (mV) are commonly used to express ripple voltage ratings. For instance, a switching power supply with a 100 mV ripple voltage rating will generate DC output voltage with a 100 mV ripple voltage.

Step 2: Connecting the Switching Power Supply to Your Motor

After selecting a switching power source, you must use a DC power cord to connect it to your motor. The suitable connectors for your switching power supply and motor should be on the DC power cord.

Connect the motor’s positive connection to the positive terminal of the switching power supply. Connect the motor’s negative connection to the negative terminal of the switching power supply.

Step 3: Operating the Switching Power Supply

You can plug the switching power supply into a 120V AC wall socket after it has been connected to your motor. the switching power supply after that. Avoid touching any exposed wires at all costs. 

Avoid overstretching the switching power supply. If the switching power supply becomes warm, shut it off right away and allow it to cool. Consult a licensed electrician if you are unsure about how to use a switching power supply securely.

Additional Considerations

If you intend to use your motor in a challenging setting, such as the outdoors or in a dusty environment, you might wish to select an enclosed switching power supply. This will aid in preventing damage to the switching power supply.

Consider using a redundant switching power supply system if your motor is being used in a crucial application, such as driving a pump or a fan. This entails connecting two switching power supplies in parallel so that your motor will still run even if one of the switching power sources malfunctions.

Frequently Asked Questions and Answers [FAQs]

Does a Switching Power Supply Require a Capacitor to Run a DC Motor?

Although a capacitor is not required, it can be utilized to reduce voltage fluctuations. Basic operation does not strictly require it.

When Utilizing a Switching Power Supply, Can I Regulate the Speed of the DC Motor?

A fundamental switching power supply typically lacks the ability to control speed. For speed modifications, a different motor controller could be required.

Can I Connect a 12V DC Motor Directly to a 120V Power Supply?

No, due to the extreme voltage, connecting a 12V DC motor straight to a 120V power supply can harm or destroy the motor.

Conclusion

The crucial step in using a switching power supply to drive a 12V DC motor on 120V AC is converting the greater voltage to a safe and appropriate level for the motor. This conversion is successfully completed by a switching power supply, guaranteeing reliable operation. If you have any questions about this electrical arrangement, see a professional.