Einführung
As a B2B buyer who purchases power supply for server rooms or data centre cabinets, you probably have encountered a problem: whether to choose 24V or 48V. These two voltages are very common in industrial power supply systems but cannot be mixed. If you choose the wrong one, you may have to spend more money on efficiency, heat and cable loss. This guide will help you clarify the key difference between these two voltages, and also help you see which one is more suitable for your specific application.
Understand the 24V and 48V power supply in the industrial power system
Let’s start from the most basic point. The power supply is to convert the alternating current in your computer room into a DC voltage that the equipment can use. The voltage in the server room and data centre cabinet is usually 24V or 48V.
24V has been used as an old industrial standard for many years. Most sensors, actuators, controllers and relays use 24V DC. This voltage is enough to drive valves and solenoid valves, and it is not high. Under the regulations of safety ultra-low voltage (SELV), it is within the touchable range.
48V has emerged later on the power distribution side. It has been used in the telecommunications system for a long time. Now it is slowly entering the data centre, AI server rack and high-power industrial equipment. The reason is very simple, because the power consumption has been going up, and 48V has less loss and higher efficiency in the transmission process.
The Open Computing Project (OCP) has clearly listed the 48V architecture as the standard for meeting the electrical, mechanical and thermal management needs of data centres. Google has been using 48V racks since 2010, which has improved efficiency and reduced losses a lot compared with the traditional 12V scheme.
Why voltage selection is important in the power distribution system
You may think, how big can the difference be if the voltage is a few volts higher? The answer is that it’s really big.
The power is equal to the voltage multiplied by the current. Under the same power, the higher the voltage, the smaller the current. The smaller the current, the less heat. The cable can be thinner, and the smaller the voltage drop when it is pulled. If the power of a rack exceeds 15kW, the system efficiency will drop to 64% if it is used with 12V. If it is changed to 48V, the same The efficiency of the rack power supply can be maintained at nearly 90%.
Which voltage choice is also related to other aspects of the system design. The smaller the current, the thinner and cheaper the cable can be used. This is the cost difference. The smaller the current, the smaller the I²R loss, and the less heat in the cabinet. This is the difference in heating. The higher the voltage, the larger the room for the later expansion. This is expandability, and also There is security compliance. Although 24V and 48V are within the SELV range, 48V is closer to the upper limit.
The system voltage in the data centre is one of the most basic decisions you can make when planning a new computer room or upgrading existing facilities.
24V and 48V power supply: 5 differences
Let’s take a closer look at the specific details. You need to figure out these five key differences before making a decision.
Effizienz
Efficiency is where 48V really dominates. After raising the DC power supply voltage from 24V to 48V, the total current is halved, and the loss on the cable is directly reduced to a quarter of the original, that is to say, the number of loads that the same power supply cable is four times the original.
The gap in efficiency in the data centre is more obvious when the power is higher. If a rack exceeds 15kW, the 48V power distribution system can still maintain nearly 90% of the power supply efficiency. It is difficult to maintain the efficiency of the traditional 24V system once the power is increased.
The efficiency of the 48V model of high-efficiency DIN rail power supply like WEHO EDR-480 series has reached 92.5%. This is not only the figure on the specification table, but also can actually help you save electricity and cooling costs.
Current level and cable loss
This is a very simple physical truth. The current of the 48V system under the same output power is only half of 24V, and the current halving the cable loss becomes a quarter.
What does this mean to you? Cable loss is not only a waste of electricity, but also heats up the cabinet. These heats have to be discharged by your cooling system, and the heat will also shorten the life of the components. You pay twice for each watt of electricity lost in the form of heat, one when it is sent out and the other with the air conditioner. When it’s time to leave
With the 48V system, the cable can be obviously much thinner. The output cable of 48V in the data centre is almost 90% thinner than that of 12V, and the space in the cable groove is saved and the material cost is also reduced.
Fever and heat management
Heat is the enemy of electronic devices. You have paid twice for each watt of electricity that turns into heat loss. One time is to generate it and the other time is to get rid of it by cooling.
The current of the 48V system is small, so there is less heat. This difference is particularly obvious in the closed cabinet and control cabinet where the air flow is not smooth. The less heat, the longer the life of the components, the lower the pressure of the cooling system, the more stable running all day, and the PUE of the data centre can also be reduced.
In fact, the 48V architecture has now become the minimum requirement for AI data centres, because thermal management is better and can support higher-density power transmission. When the AI workload pushes the power demand higher and higher, it becomes particularly critical whether the heat dissipation can keep up.
Application scenario
24V is still used a lot in old industrial scenarios, such as traditional control cabinets, sensor actuator relays, PLC systems and automation equipment, and those systems that have long been designed according to the 24V standard.
48V has slowly become mainstream in data centre server racks and AI infrastructure. 48V is more suitable for high-power telecommunications and network equipment, systems with long cables, and high requirements for efficiency and heat dissipation.
| Unterschied | 24V System | 48V System |
| Effizienz | Drops significantly above 15kW per rack | Keeps ~90% efficiency; WEHO EDR-480 reaches 92.5% |
| Current & Cable Loss | Higher current = higher loss = more heat | Half the current = quarter the loss; cables 90% thinner |
| Heat Management | Runs hotter, stresses cooling systems | Runs cooler, extends component life, lowers PUE |
| Application Scenarios | Traditional controls, sensors, PLCs, legacy gear | Data centers, AI racks, telecom, long cable runs |
How should you choose between 24V and 48V systems?
So which one should you choose? The following judgement method can help you make a decision.
Suitable for choosing 24V——Your equipment is originally designed according to 24V, such as sensors, actuators, relays and traditional PLCs all belong to this category. The power demand is not high, less than 5kW per cabinet, and the cable is not more than ten metres long. You want to replace the existing 24V system, want to maintain compatibility and don’t toss, you The application belongs to standard industrial control rather than high-performance computing. In this scenario, 24V is still the old main force you are familiar with.
Suitable for choosing 48V——You are building a new data centre or server room from the beginning. The rack power requirement is more than ten to fifteen kilowatts, and the cable should be pulled more than ten metres long. You are worried that the heat in the closed cabinet cannot be dissipated. You want to leave room for expansion for future power distribution. What you need to deploy is AI, high-performance computing or high Density server infrastructure, 48V has become an industry trend in these scenarios.
In addition, you don’t have to choose one or the other. Some systems take a hybrid route, using 48V for power distribution, and then turning it to 24V for local equipment when it reaches the load. In this way, you can not only get the high efficiency of 48V power distribution, but also supply 24V equipment normally. If you need to use the equipment with voltage on both sides This scheme is actually quite practical.
WEHO Industrial Power Supply Solution
Whether you choose 24V or 48V, you need a supplier you can trust. WEHO (Zhejiang Weihao Electronic Co., Ltd.) has been manufacturing industrial power supplies for over 16 years, with SGS and BV certifications that demonstrate their commitment to quality and compliance.
WEHO offers both 24V and 48V models across multiple product lines to meet your specific requirements.
Der EDR Series DIN Rail Power Supplies are available in 24V and 48V models. The EDR-480 delivers 480W output with 92.5% efficiency, operating across a universal input range of 85-264VAC. Comprehensive protection features, including overload, over-voltage, and short-circuit protection, guarantee the safety and longevity of your equipment. This series is ideal for data center cabinets, control panels, and industrial automation systems.
Der HDR Series DIN Rail Power Supplies are designed for industrial automation applications, offering reliable performance in harsh environments. The DR Series DIN Rail Power Supplies provide single output with full range input, making them suitable for a wide variety of industrial power distribution needs.
WEHO’s in-house engineering team supports custom and OEM/ODM projects, so you can get the exact output voltage, current rating, or enclosure design your application requires. Their manufacturing experience and quality assurance systems meet global standards, making them a reliable partner for B2B buyers looking for 24V or 48V power solutions for server rooms and data center cabinets.
FAQ
Can 24V systems still be used in industrial cabinet power design?
Yes, absolutely. 24V remains the standard for most industrial control applications—sensors, actuators, relays, and PLCs. If your equipment is 24V-compatible and your power needs are moderate, 24V is still a solid choice.
Why is 48V preferred for high-efficiency power distribution systems?
Because 48V draws half the current of 24V for the same power. Half the current means a quarter of the cable losses. This translates to higher efficiency, less heat, and the ability to use thinner cables. For racks over 15kW, 48V systems maintain nearly 90% efficiency while 24V systems drop significantly.
How does voltage level affect heat generation in enclosed cabinets?
Heat generation is proportional to the square of the current (I²R losses). A 48V system draws half the current of a 24V system, so it generates significantly less heat. This is critical in enclosed cabinets where airflow is limited and heat can shorten component life.
Is 48V safe for industrial continuous operation systems?
Yes. 48V remains within the Safety Extra-Low Voltage (SELV) range, which simplifies insulation, protection, and system certification. It is widely used in telecom, data centers, and industrial applications that run 24/7.
Does WEHO support customized AC-DC output voltage and enclosure design?
Yes. WEHO has in-house engineering capabilities to support custom designs. They can adjust output voltage, current, and power ratings, as well as modify enclosure designs to fit your specific installation requirements. For OEM and ODM projects, WEHO offers flexible manufacturing services.
Abschluss
Choosing between 24V and 48V is not about which one is “better”—it is about which one fits your application. 24V is reliable, widely supported, and perfect for traditional industrial controls. 48V is efficient, scalable, and the clear choice for high-power data center and AI infrastructure.
Look at your power requirements, cable runs, heat constraints, and future expansion plans. If you are building new, 48V gives you more headroom. If you are maintaining legacy equipment, 24V is still the workhorse.
Whichever you choose, make sure your supplier has the certifications, product range, and engineering support to back it up. WEHO offers both 24V and 48V solutions with the quality and reliability that B2B buyers demand. Choose the voltage that fits your needs—and choose a supplier you can trust.
