Overview of major wiring harness products

The wiring harness is like the blood vessels and nerves of industrial equipment. With the development of industrial intelligence, the market demand is increasing, and quality requirements are higher. The process requirements are becoming more complex as well.

Wiring harnesses are found everywhere in life and are mainly used to connect the circuits inside each electrical device. They are composed of terminals, insulation wrapping material, insulation sheath, and wire. As the carrier of input and output current and signals, knowing its types and applications is important. Today, we will summarize and share them.

Wire Harnesses
Wire Harnesses

Overview of the types and product applications of wiring harness

Wiring harnesses are a major industry in today’s electronic age with the fastest growth rate, the largest market demand, and the easiest installation process. The popularity of home appliances, communication equipment, computers, and other external equipment, as well as security, solar energy, aircraft, automotive, and military instrumentation, means that wiring harnesses are widely used.

A wiring harness is composed of different wires and cables depending on the circuit, hole, position, and electrical principle requirements. Different models, terminals, plugs, external protection, and nearby systems are combined to create a wire harness assembly.

There are four main functions of the product: screen wiring harnesses, control harnesses, power supply control, and data transmission.

Harnesses are classified according to their use such as railway locomotive, automotive, wind power connection, medical, communication, home appliance, and industrial control wiring harnesses.

Wiring harnesses are essential to achieve the electrification of the future and are the necessary foundation of the product for the information society.

The following are common wiring harness products, how many have you seen?

  • Driving screen wiring harnesses, mainly used in a variety of display drive lines, as long as it is used in the field of display are involved.
  • Control harnesses are mainly used to connect the circuit board to control the electrical signals, financial equipment, security equipment, new energy vehicles, and medical equipment field.
  • Power control wires, such as switching power lines, computer power lines, and so on.
  • Data transmission lines, upload and download signals, such as HDMI, USB, and other series.

Wire harness application classification of the automotive wire harness

The automobile wire harness is the main body of the automobile circuit network. Without a wire harness, there would be no automobile circuit. A harness is made of punched copper with connectors and terminals crimped to wire and cables, and then covered with plastic pressure insulation or an external metal shell, forming a circuit component connection bundle. The body harness connects the entire body and is generally an H-shape.

The wiring harness ensures that the electrical and electronic components of a car connect and function. Luxury cars and ordinary cars have almost identical wiring harnesses composed of wires, plugs, and wrapping tape, which ensure reliable transmission of electrical signals and current values to prevent electromagnetic interference with surrounding circuits.

The power lines and signal lines carry power to the actuator and sensor input instructions, respectively. The power line carries large currents through thick wires while the signal line is a thin wire that does not carry power.

Conventional automotive wiring harnesses have heat-resistant, oil-resistant, and cold-resistant characteristics. At the same time, they are highly flexible and used for internal connections in automobiles. They can adapt to high mechanical strength and high-temperature environments.

With the development of intelligent technology, cars are no longer just engines on frames with rows of sofas, they are complex computers connecting to everything from offices to entertainment. Therefore, automotive wiring harnesses must meet higher electrical performance requirements for wire quality and quantity. Quality must meet the requirements of TS16949 zero defects, and maintain an effective quality assurance period of 10 years.

The demand for new energy vehicles has skyrocketed in recent years, and suppliers must provide a complete set of wire and cable design and development programs and a full set of services for manufacturers. Therefore, new entrepreneurs entering the industry must understand the threshold and requirements of the automotive wiring harness.

Harness application classification of medical wire harness

A medical wire harness, as the name suggests, is used in medical equipment to support the connection of wire harness products. It is an essential component of medical electronic equipment, as without it, the equipment cannot run normally.

The wires used in medical wire harnesses are of high quality and are certified by UL, VDE, CCC, JIS, and other standards.

Commonly used medical connectors include wire-to-board connectors, D-SUB connectors, rows of pins, and rows of female, as well as aviation plugs. International brands such as TYCO and MOLEX are the most commonly used. Medical wire harnesses are certified based on the 13485 medical certification, and most of the materials need to be sterilized.

The research organization, BCC Research, has pointed out that as the global market size of home medical equipment continues to rise, medical electronics will become the connector application of the new growth point. Aspiring entrepreneurs in this industry must understand the threshold and requirements of the medical wiring harness.

The medical wiring harness is made of electronic wire, which is cut to length according to drawings. Copper is then punched into the contact parts of the terminals (connectors), and wire and cable crimping is done. After this, the harness is covered with a moulded pressure insulator or additional metal shells to form a connected circuit of components. This is known as the control harness.

Due to the high-risk and high-precision characteristics of the medical industry, the standards for medical device production are different from those of general instruments. The inspection standards for medical devices are the most stringent among all the standards.

Wire harness application classification of industrial product harnesses

Industrial products with wire harnesses mainly refer to cabinets with components including electronic wires, multi-core wires, rows of wires, etc. These are mostly used in industrial cabinets such as UPS, PLC, CP, inverters, monitoring, air conditioning, wind energy, and other systems.

The wiring harness category has the largest number of practitioners, with many types including sensors and industrial control systems, network communications, temperature control, air conditioning, LED and lighting, rail transportation, marine and offshore engineering, renewable energy, measurement and test equipment, packaging, and logistics transmission.

The main challenge in industrial wire harness production is managing an extensive range of parts and components from various locations around the world. Coordination with suppliers for timely delivery of materials is crucial to ensure on-time delivery of finished harness products. This demands a high level of supply chain management capability from the factory.

Harness application classification of the robot harness

To ensure a robot performs accurately and efficiently, its internal connections must be free of errors. The crimped wire harness used in Robot Wire Harness is crucial and must adhere to strict standards for stability and reliability.

With rising labour costs, robots are increasingly being used in industrial fields, replacing humans in performing complex tasks. Consumer services are also adopting robots, leading to new opportunities. Unmanned cash registers and food delivery robots in supermarkets, restaurants, and production lines are some examples. With these developments, we are truly in the 3.0 era of robotics.

Industrial robots used by cable manufacturers require the use of different parts with specific characteristics. What types of industrial robots are used by manufacturers of wires and cables? Wires and cables for robots are generally divided into signal circuit cables and power circuit cables.

A: Signal circuit and power circuit, mainly used for rotating parts or wrist parts, such as extreme bending and twisting parts of the super-resistant bending cable or spring cable.

B: Also divided into signal and power circuits, this is a bending-resistant cable mainly used for general joints and other parts where the frequency is less than that of A and conditions are gentler.

C: Signal circuit, mainly used for the guide box wire, because of the need to operate the use of the cable needs to have a flexible.

D: Divided into signal and power circuits, it is mainly used as a contact cable between the robot and the control device and is divided into fixed wiring and mobile wiring in terms of the method of use.

E: Divided into signal and power circuits, these cables are mainly used for fixed wiring inside machines such as control devices.

Wire harness application classification of banking equipment harnesses

Bank equipment harness (Industrial Wire Harness) can generally be used for banking equipment, including window intercom, queuing machine, LED display, interest rate screen, ID card identifier, window charging system, bank intercom, check identifier, automated teller machine (ATM), automatic deposit machine, circular automated teller machine (CRS), self-service inquiry machine, and self-service bill payment machine. The harness terminals generally use TYCO connectors, AMP connectors, or other similar connectors.

With the increasing popularity of a cashless society and the introduction of digital currency policies, there has been a trend towards downsizing banking equipment. As a result, the future of banking equipment harnesses will experience a significant reduction. Therefore, if companies are still mainly engaged in the production of these harnesses, they should consider diversifying their offerings for sustained growth. This could include developing robotics harnesses, automotive harnesses, and other related harness categories.

Harness application classification of communication data, security harnesses

Communication data and security harnesses come in a variety of types, including closed-circuit monitoring, burglar alarms, access control attendance cards, network engineering, parking management, smart homes, intelligent offices, visual intercoms, conference systems, and intelligent audio and video.

With the future upgrades to the 5G network, existing products will see a surge in demand. Due to the substantial increase in demand and existing volume, the unit price is similar to consumer products. The main price difference lies in the application of electronic product programs. Therefore, if you are a new entrepreneur ready to enter the industry, be sure to understand the volume of demand and the matching financial situation.

Currently, the mainstream market uses SFP28/SFP56 and QSFP28/QSFP56 IO modules to connect cabinets between switches and switches, switches, and servers. However, with the increasing demand for higher port density in the 56Gbps rate era, QSFP-DD IO modules were developed to offer 400G port capacity. These modules have 8 high-speed channels, and each channel can transmit at a rate of 112G PAM4. With a total transmission rate of 800G, it is backwards compatible with the OSFP56 and meets IEEE 802.3CK Association standards. However, the rate increase also results in a sharp increase in link loss, which reduces the transmission distance of passive copper IO modules.

Based on physical constraints, the maximum length of copper links has been reduced to 2 meters as specified by the IEEE 802.3CK group.

Although there has been significant progress in helping data centres upgrade to 400G and 800G, the right timing for the transition is still a challenge for operators due to the rapid pace of technology development and refresh cycles.

Harness application classification of the UPS series of industrial control harnesses

With the widespread economic development of computers, certain critical places such as the financial, information, communications and industrial control sectors are increasingly demanding their power supply reliability and stability. For example, industrial control systems require a high-quality and stable power supply.

In case of sudden power failures, a power supply is needed to maintain service for a certain period. This is crucial to ensure the safety of field instrumentation and control valves, as well as to protect industrial control system data and prevent accidents. Therefore, the UPS series of industrial control wiring harnesses plays a significant role.

These harnesses are mainly used in electronic and electrical products and are essential in several industries including telecommunications, automotive, and instrumentation for industrial automation equipment.

Additionally, they are also used in sectors such as medical, aviation, railroads, and transportation where AC uninterruptible power supply systems like UPS and power distribution are in use.

The industrial uninterruptible power supply (UPS) consists of two parts: the host and the battery. The harness mainly comprises power control lines, such as switching power lines and computer power lines. The delay time for the power supply depends on factors such as the matched battery capacity, load, and the cross-sectional area of the cable.

Harness manufacturers typically configure the power control harness according to the standard requirements of the customer and the AWG number of cables required for power control.

Wiring harness application classification of home appliance wiring harness

The home appliance wiring harness products are mainly used for internal signalling, electricity, power transmission, and machine control within home appliances.

Examples: air conditioning power harness, water dispenser harness, computer internal power cord, coffee machines, egg beaters, other signal lines, TV harnesses, etc. We can call the product harness for white goods and home appliances, as it is the main body of the network circuit, and without these harnesses, there would be no home appliance circuit.

Currently, high-end luxury appliances and low-end common household appliances have the same basic form of wiring harnesses, which are made up of wires, connecting plug-ins, and wrapping tape.

Home appliance wires, also known as low-voltage wires, are not the same as ordinary household wires. Normal household wires are single-conductor copper wires with a certain degree of hardness, while appliance wires are made up of multi-strand soft copper wires wrapped in plastic insulation tubes (PVC). Some soft lines can be as thin as a hair, while others can have dozens of soft copper wires.

The common specifications for appliance harness wires include a nominal cross-sectional area of 0.5, 0.75, 1.0, 1.5, 2.0, 2.5, 4.0, 6.0, and other square millimetres of wire, allowing for different power loads and different specifications for electrical equipment.

The wiring harness for home appliances is currently one of the most basic products available. It has low technical content and the supply chain involved is quite simple. Many of the factories producing these harnesses are small workshops and they mainly focus on producing supporting products for home appliances.

Wiring harness application classification of the railroad locomotive wiring harness

The wiring harnesses for railroad locomotives are mainly used for connecting the electric power system (including two- and three-phase power supply input and output), communication system (including the new railroad bus door control, closed-circuit television, communication, and telecommunication signals), control system (for connecting the railroad electrical part of the control system), and the internal electrical system.

With the rapid pace of urbanization, the core technology of subway vehicle design and installation is constantly evolving. When it comes to the subway vehicle electrical wiring assembly process, attention should be paid to ensuring that the weight of each compartment is the same and that the electrical wiring is uniformly distributed among each unit of the compartment. This will ensure the stability of the subway vehicle while driving, as well as the normal operation of the subway vehicle brake function. These measures aim to improve the service life of the subway vehicles.

The wiring harness requirements are very complex, and there are specific requirements for wiring that general enterprises may find difficult to meet. Obtain the relevant product production qualifications to fulfil these requirements.

The application of wire harness classification of wind power generation wire harness

The wind power connection cable is mainly used for the connection of the inverter system, the control system inside the cabinet, and the link of wind turbine blades, gearboxes, nacelles, and towers. Since wind farms are usually located in areas with severe weather conditions, the main features of this product are low-temperature torsion resistance and cable flexibility at low temperatures. The cable must maintain excellent electrical and mechanical properties in environments ranging from -50℃ to +80℃.

Wind power “reliability” is key to choosing connectors. Price is no longer the primary factor in the decision-making process. From the cable to the connector, large industry manufacturers are responsible for the materials used, resulting in generally good profit margins for this part of the process.

Wiring harness application classification of other types of harnesses

Of course, a wiring harness will certainly not be as small as the few types of collated. In general, the above-mentioned types of wiring harnesses are currently the mainstream products. Wiring harnesses for other applications including aerospace, marine, construction, energy, instrumentation, and military- among others.

  • In the aerospace field, wiring harnesses are used to connect various electronic devices and sensors of the aircraft to ensure the safe operation of the aircraft.
  • In the marine industry, wiring harnesses are utilized to connect the ship’s power, navigation, and communication systems, ensuring the proper functionality throughout navigation.
  • In the construction industry, wiring harnesses are utilized to connect the lighting, security, and fire-fighting systems of buildings to ensure their safe operation.
  • In the energy industry, wiring harnesses are used to connect various equipment and facilities in power plants, substations, and distribution stations to ensure the safe transmission and distribution of electricity.
  • In the field of instrumentation, wiring harnesses are used to connect the sensors and displays of various instruments to ensure the normal operation of the instruments.
  • In the field of military industry, wire harnesses are used to connect electronic equipment and sensors on various weapons and equipment to ensure their normal operation. Similarly, in the field of security, wiring harnesses are used to connect all kinds of security equipment and facilities to ensure the proper functioning of the security system.


In recent years, there has been rapid development in the electric vehicle manufacturing industry, and the popularity of the 5G communications market means that there is a rising demand for wiring harnesses to support these industries. This increase in demand is conducive to promoting the development of wiring harness production equipment.

As the market for wiring harness products has grown, there are increased requirements for both quality and productivity. Some traditional manufacturers have been unable to integrate into the latest developments in this field. However, with the continued development of automation technology, precision, and efficient operation in the wiring harness industry, there is potential for independent innovation throughout the industry chain.

Manufacturers will need to carry out infrastructure upgrades on the relevant industry chain to meet these needs, which will ultimately result in the production of high-quality products for customers in large numbers.

If you want to know more about customized solutions for high-end wiring harnesses, please contact us, Romtronic is a leading manufacturer of customized cable assemblies and wiring harnesses with 27 years of OEM and ODM experience.