You've probably already heard of 12 VDC , but do you know what it means and what it's used for? 12 VDC is a direct current voltage widely used in electronics and electrical engineering . It offers many advantages over the alternating current (AC) that comes out of our wall sockets , but it also requires a specific device to produce it. In this article, we'll explain what 12 VDC is, its advantages, and how to choose the power supply for your needs. Follow the guide!
What is 12 VDC?
12 VDC is an abbreviation for 12 volts direct current . It is an electrical voltage used to power many devices and equipment, such as LED lamps, fans, security cameras, phone chargers, and more. 12 VDC is a stable and safe voltage that does not fluctuate with the frequency of the electrical grid .
What are the advantages of 12 VDC?
The 12 VDC system offers several advantages that encourage you to use it for your electrical installation:
- It allows power to be supplied to devices which operate at low voltage , which reduces energy consumption and operating costs.
- It reduces the risk of electrocution or fire , as it does not cause sparks or electric arcs.
- It facilitates the transport and storage of energy , as it can be used with batteries or solar panels.
- It offers better current quality, without noise or interference , which improves the operation and lifespan of the powered devices.
But how do you get 12 VDC from the alternating current (AC) coming out of your wall sockets? That's where 12 VDC power supply come . These devices convert alternating current to direct current , reducing the voltage and filtering out interference. There are different types of 12 VDC power supply , depending on the current conversion method and the power output.
The different types of 12 VDC power supply sources
We can distinguish two main categories of 12 vdc power supply sources: linear power supply sources and switching power supply sources.
Linear power supply sources
Linear power supplies are the simplest and oldest type. They use a transformer to step down the alternating current voltage , then a rectifier to convert it to direct current. Finally, a regulator ensures the stability of the output voltage. power supply power supply have the advantage of being inexpensive, quiet, and producing good-quality direct current without noise or interference. However, they are not very efficient because they dissipate a large portion of the energy as heat. Therefore, they are bulky, heavy, and require cooling.
Switch-mode power supply sources
Switch-mode power supplies are more modern and efficient. They use an electronic circuit that chops the high-frequency alternating current (AC) and then converts it to direct current (DC) using a chopper. A filter then smooths the current, and a regulator adjusts the output voltage. power supply power supply have the advantage of being more efficient because they minimize energy losses. They are therefore more compact, lighter, and generate less heat. However, they are more expensive, more complex, and noisier. They can also generate electromagnetic interference with nearby devices.
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How to choose your 12 VDC power supply ?
To choose your 12 VDC power supply , several criteria must be taken into account:
- Power power supply must be able to provide enough current to power all connected devices . Power is measured in watts (W) or amps (A) . Therefore, you need to know the power consumption of each device in watts or amps, then add them up to obtain the total power required.
- Efficiency : This is the ratio between the power supplied and the power consumed by the power supply . The higher the efficiency, the less energy the power supply choosing a power supply with high efficiency is essential to reduce your electricity bill and your environmental impact.
- Quality : This refers to the stability and purity of the current supplied by the power supply . The higher the quality, the less susceptible the current is to voltage fluctuations or interference. Quality is measured in decibels (dB) or as a percentage (%). Therefore, it is essential to choose a power supply with high quality to avoid malfunctions or damage to the connected devices.
- The format : this refers to the shape and size of the power supply . Various formats exist, such as flush-mounted power supply , DIN rail power supply modular power supply power supply , etc. Therefore, you must choose a format that is suitable for the available space and the desired mounting method.
- The price : this refers to the purchase cost of the power supply . It varies depending on the power output, efficiency, quality, size, and brand of the power supply . It is therefore necessary to compare offers and choose the best value for money.
Comparative table of 12 VDC power supply sources
To help you choose your 12 VDC power supply , here is a comparison table of some models available on the market:
| Model | Kind | Power | Yield | Quality | Format | Price |
| MEAN WELL RS-15-12 | A cut-out | 15 W | 82 % | ±1 % | Built-in | 9 € |
| SL Power SLS12-017T | Linear | 18 W | 60 % | ±0.05 % | Plug-in | 25 € |
| TDK-Lambda ZWS10-12/J | A cut-out | 10 W | 80 % | ±0.5 % | On DIN rail | 35 € |
| Bel Power Solutions HB12-1.7-AG | Linear | 20 W | 50 % | ±0.04 % | Chassis | 40 € |
| CUI Inc. VOF-180-12-CNF | A cut-out | 180 W | 90 % | ±1 % | Modular | 50 € |
FAQ about 12VDC
What is the difference between 12 VDC and 12 VAC?
12 VDC is a direct current voltage, which does not change direction or value. 12 VAC is an alternating current voltage, which changes direction and value at a given frequency (50 Hz or 60 Hz depending on the country). 12 VDC is more stable and safer than 12 VAC, but it requires a power supply to be converted from alternating current.
What are the disadvantages of 12 VDC?
The 12 VDC also has some disadvantages:
- It requires a power supply source to be obtained from alternating current, which implies an additional cost and energy loss.
- It suffers power losses when traveling long distances or passing through cables of small cross-section, which necessitates the use of larger wires or an increase in voltage.
- It is not compatible with certain devices that operate on high voltage or alternating current, such as electric motors, microwave ovens, air conditioners, etc.
How to choose components for a 12 VDC power supply ?
To choose components for a 12 VDC power supply , you must consider the power requirements of the devices to be powered, the input voltage of the electrical grid, and the type of power supply (linear or switching). Next, you must select a transformer suited to the input voltage and desired power, a rectifier to convert alternating current to direct current , a regulator to stabilize the output voltage, and capacitors to filter the current. You must also comply with safety and electromagnetic compatibility standards.
What does the 12 vdc refer to in the description of a fan?
The 12 VDC in a fan's description refers to the fan's power supply . This means the fan must be connected to a power power supply that provides 12 VDC . This could be an power supply or an internal connector on the computer's motherboard. The 12 VDC also indicates the fan's noise level and power consumption. The higher the voltage , the faster and noisier the fan spins, but the more effectively it cools.
How to get 12 VDC from 24 VAC?
To obtain 12 VDC from 24 VAC , a voltage converter is required to step down the alternating voltage and convert it to direct voltage. Several types of voltage converters exist, such as resistive voltage dividers, single or double rectifier bridges, and linear or switching regulators. The converter must be chosen based on the required power and desired efficiency. It is also essential to observe correct polarity and protect the circuit against overvoltages .
Conclusion
12 VDC is an electrical voltage used to power many devices and equipment . It offers advantages in terms of safety, stability, and energy efficiency, but it requires a power power supply to convert it from alternating current. There are different types of 12 VDC power supply , distinguished by their current conversion method, power output, efficiency, quality, and form factor. To choose the right 12 VDC power supply , you must consider these criteria, as well as the price and the power requirements of the devices you need to run. We hope this article has helped you better understand 12 VDC and make the right choice for your electrical installation .
