Three-Phase Distribution Board

What is a Three-Phase Distribution Board

그만큼 three phase electrical panel board is actually a core device that helps you steadily distribute the three-phase power supply to each power circuit. It is standardly equipped with protective devices such as circuit breakers, and some also come with leakage protection devices. It can block the risks of overload, short circuit, or leakage at critical moments.

Its main function is to rationally distribute three-phase electricity to different areas. When problems occur, it automatically cuts off the power to prevent the fault from expanding, and it can also isolate the circuit for convenient maintenance. It is commonly used in places with high electricity consumption, such as general industrial plants and shopping malls. It is also indispensable for residential buildings with high-power equipment installed or secondary power distribution.

The Structure of the Three-Phase Distribution Board

Main switch

 It is equivalent to the main valve of the entire distribution board and can completely cut off the power supply during maintenance or emergency situations. You can choose 3-pole or 4-pole equipment with a rated current three times the full-load current. The 3-pole is suitable for pure three-phase loads, and the 4-pole has an additional neutral wire, which can also handle single-phase power consumption. It depends on your actual needs.

버스바

It is made of copper or aluminum bars and evenly distributes the input electricity to each branch. Copper busbars conduct electricity well but are expensive, while aluminum busbars are cheaper but prone to oxidation. 

회로 차단기

The protection core is in the circuit breaker. For instance, if a D-type trip curve is used for the motor circuit and a C-type for lighting, the load characteristics must be matched. If it is too small, the arc cannot be extinguished in case of a major fault, which is dangerous.

Residual current protection device (RCD) 

Integrated with circuit breakers to form an RCBO saves more space. It trips within 0.1 seconds when a person is electrocuted or there is a leakage in the line. A damp environment (such as the kitchen) is a must. After all, survival comes first.

Neutral wire bar and ground wire bar

Mixing them together can easily cause interference. The screws should be tightened. Poor contact can cause unstable voltage and even burn out the equipment.

Shell

If you are going to place the three-match circuit board in a dry indoor environment. Just use IP42. It’s dust-proof and splash-proof. If it is to be placed outdoors or in a workshop, an IP66 model should be chosen. For plastic, choose flame-retardant types. Safety comes first.

Label

Each circuit breaker clearly defines the control area, such as “1st Floor Lighting” and “Workshop Fan”, with a uniform color (red off and green off) and serial number. Later maintenance can be easily identified at a glance.

Three-Phase Distribution Board Types

The main distribution board (MDB) 

It is installed in the main power room of the building, connected to the high-voltage electricity from the external power grid. After passing through the main incoming line circuit breaker, fuse, and other protective devices, it is then distributed to each sub-board. It can withstand large fault currents, with a rated current often exceeding 800 amperes, and serves as the safety door for the entire power supply system.

Distribution Board (SDB)

After drawing power from the MDB, it is exclusively used to supply power to specific areas or equipment. For instance, in the shopping mall, there are separate SDB systems for lighting, air conditioning, and each floor. It is small in size, with a rated current mostly ranging from 100 to 400 amperes. It can be installed in places where your electricity usage is concentrated, making it convenient to add circuits later.

Split-Load Boards

The circuit was disassembled into several parts. For instance, one tube is used for ordinary sockets and lights, while the other is for sensitive devices such as computers and medical equipment. In this way, if one circuit malfunctions, the others can still function normally. It is particularly suitable for places with high requirements for power supply continuity.

Motor Control Center (MCCs)

It integrates motor starters, contactors, and even frequency converters (VSD), capable of automatically controlling the start, stop, and speed regulation of motors. The pump equipment on the production lines and in the workshops of the factory can save a lot of wiring effort by using it. It also has overload and phase loss protection, making the machines safer.

Combination Boards

They mix single-phase and three-phase circuits and are suitable for places with limited space, such as small shops and workshops. You need to connect a three-phase motor and reserve a single-phase socket at the same time. Choosing this one is the right choice.

The advantages of a three-phase electric board.

Three-Phase Distribution Board Application Field

Industrial Manufacturing

In industrial workshops and manufacturing plants, the 전기 패널 is the core for you to ensure production. The large machine tools, stamping equipment, and automated production lines here all rely on three-phase electricity to provide stable power. It can evenly distribute electricity, avoid shutdown caused by single-phase overload, and ensure the continuous and efficient operation of your production line.

Commercial Building

Central air conditioning, elevators, lighting systems, and refrigerated cabinets in large shopping malls, these high-energy-consuming devices all require three phase electrical panel board for electrical support. The three-match circuit board can flexibly allocate power, ensuring that the lights and air conditioners in the shopping mall do not trip even when all are on during peak hours, providing customers with a comfortable shopping experience.

High-End Residence

In high-rise office buildings and apartments, the panelboard is responsible for the power supply of the entire building. From elevator operation to the fire protection system, from public area lighting to household air conditioning, it delivers electricity steadily to every corner. Especially for high-rise residential buildings, three-phase electricity can also reduce line losses, allowing residents on the top floor to use electricity with peace of mind.

The Medical Field

Hospitals and data centers have extremely high requirements for power stability. The operating rooms, ICU equipment, MRI machines in hospitals, and server clusters in data centers will have serious consequences if power is cut off. The 배전반, in combination with the backup power supply, can achieve millisecond-level switching, safeguarding the security of your life equipment and core data.

The Field of Agriculture

In agricultural facilities and irrigation systems, three-match electrical boards drive high-power water pumps and greenhouse temperature control equipment. Whether it is large-scale sprinkler irrigation or intelligent temperature-controlled greenhouses, it can provide continuous power and help you improve agricultural production efficiency.

Electric Vehicle Charging Piles

When multiple charging piles work simultaneously, the power is large, and the three-match distribution board can efficiently distribute electricity. Avoid grid overload during charging queues and provide a guarantee for car owners to replenish their energy quickly.   

Single-Phase Distribution Board vs. Three-Phase Distribution Board

Single-Phase Distribution Board

220V alternating current is transmitted through a live wire and a neutral wire, and the direction of the current changes unidirectionally over time.

장점

• Simple structure and convenient installation.
• Low cost.

Disadvantage

High-power electrical appliances have a large starting current and are prone to tripping.

Applicable Scenarios

Ordinary families, small shops, and places mainly for lighting.

Three-Match Circuit Boards

The three live wires (L1/L2/L3) are each 120 degrees apart in phase and share the neutral wire or ground wire. The 380V line voltage is provided by two-phase live wires, and the 220V phase voltage is provided by a single live wire, one or the other.

장점

• Stronger and more stable electricity.
• When three phases are supplied simultaneously, the total power is three times that of a single phase.

• Small voltage fluctuation.

• Significant efficiency improvement: Under the same power, the wires are thinner and more cost-effective, with lower heat loss.
• The motor operates more smoothly: Three-phase electricity generates a constant rotating magnetic field, enabling the motor to start quickly, generate low noise, and have a long service life.
• Flexible compatibility with various loads: It can be connected to three-phase equipment (water pumps, welding machines). It can directly supply power to single-phase sockets and lamps without the need for additional transformers.

Applicable Scenarios

factory workshops, shopping malls, data centers, high-end residences (whole-house central air conditioning + floor heating), and any place that requires high power or continuous power supply.

요약

If your industry involves industrial equipment, high-power commercial appliances, or may expand in the future, three-match circuit boards are a must. In the long run, it has strong stability and can save electricity. As a purchaser, it is definitely cost-effective to plan the three-phase system in advance.

How to Choose the Suitable Three Electricity Panels

Computing Load

Don’t just focus on the functions of individual devices. Add up all the related items and then use the diversity coefficient. Make sure your busbar load is normal.

Short-Circuit Assessment

You need to know how large the short-circuit current at the installation is. The distribution board must be able to withstand this impact. Thermal stress can melt copper bars. Mechanical stress can crack the casing. Do not be tempted by low prices and buy products from small factories.

Cable Selection

If the cable is too long or too thin, the voltage at the end may drop below the standard. If necessary, use thick wires or set up distribution boxes nearby.

Heat Dissipation Requirements

If the spacing is insufficient and ventilation is poor, the insulation will age rapidly as the temperature rises, and the failure rate will soar. If the environment is sealed, you can install a fan to dissipate heat. Don’t fill it too full in ordinary situations either. Leave some space for the heat to escape.

향후 확장

When planning now, leave an additional 20% to 30% of the current margin and don’t fill up the physical space. In the future, when adding equipment or upgrading the system, there’s no need to disassemble and reinstall it. Especially for commercial projects, business growth is rapid. Reserving this aspect can save a lot of trouble.

인클로저 보호

The IP rating depends on the environment: For damp and dusty conditions, choose IP54 or above; for outdoor use, IP65 is recommended. IK level impact resistance, bumping around in the workshop, at least IK10. Don’t underestimate this.

Installation Convenience

Leave sufficient operating space at the front and a maintenance passage at the back. It is also recommended that you take lighting into account. This will make it more convenient for you to carry out maintenance at night.