Power connectors - Types and applications in Industry

In industrial production, reliable and high-performance connectors are essential to safely power machines, motors, and control systems. Power connectors play a special role in this process, from CEE connectors that provide a standard-compliant power supply to hybrid connectors that combine power and data transfer in a single interface. In this blog, you’ll learn what matters when selecting, isolating, and shielding power connectors, and how they help improve efficiency and reliability in industrial applications.

What are power connectors?

A power connector is an electrical connector that primarily serves to transmit high electrical power safely and efficiently. Unlike other types of connectors responsible for transmitting signals or data, a power connector is specifically designed to handle higher currents and voltages typically found in industrial applications such as machine controls, automation systems, control cabinets, or power supply units.

Unlike power connectors, data connectors are designed to transmit digital or analog data. They are not optimized for high currents and voltages, but rather for the transmission of low power values, such as those found in communication technology. Signal connectors, in turn, are used for control and regulation tasks, e.g. for sensors, control elements or measuring systems, where the transmission of electrical control signals is involved. Thus, power connectors are specifically designed to function in high electrical power applications, while data and signal connectors are primarily responsible for communicating data or signals at low voltages and currents.

Power connector properties

Power connectors transmit electrical power. Electrical power is the amount of electrical energy per unit time that is conducted through the connector from a source to a load. A power connector must therefore be designed for a certain electrical power, since it can otherwise overheat or fail mechanically as well as electrically. The decisive factor for this is the current rating in amperes (A), which indicates how much current the plug can safely conduct without causing overheating or contact problems. In addition, the maximum operating voltage (volts, V) plays a role for which the plug is designed. However, efficient electrical insulation is also necessary so that power and high currents can be transmitted safely.

The material selection of contacts such as copper or contact-enhancing, silver- or gold-plated coatings ensures low transition resistance and high load capacity. In addition, the plug must have an appropriate protection class (IP protection) depending on the operating environment to protect it from dust, moisture and mechanical stress. A secure connection is ensured by the appropriate design and locking, for example by bayonet locks or screw locks, which prevent unintentional loosening.

Structure of Power Connectors

A power connector consists of several components that together ensure safe and efficient energy transmission. The housing, for example made of plastic or metal, protects against external influences and can consist of antistatic materials if necessary to protect sensitive electronic components. It also has coding features to prevent accidental contact swapping due to incorrect insertion. The contact carrier, usually made of high-performance plastics, serves as an insulating carrier for the electrical contacts and is designed for high temperature and dielectric strength. The electrical contacts, usually made of copper alloys and often silver-plated or gold-plated, minimize transition resistance and are designed as spring contacts, screw contacts, or crimp joints depending on the design to ensure reliable contact. A locking system, designed as a screw, bayonet, or snap lock depending on the application, provides secure fixation and protects the connector from vibration or unintentional release.

Types of Power Connectors

Power connectors come in different designs and versions that meet different requirements depending on the application area. They differ in performance, design, protection class and functionality to meet the specific needs of industry, automation and electrical engineering. While some connectors are designed exclusively for pure energy transmission, others additionally combine control and data cables to efficiently network complex systems. They also vary in mechanical interlocking, protective measures and electrical specifications to ensure safe operation under various environmental conditions.

A classic example of a power connector is the M23 power connector, which features a compact design and high performance. However, the M23 plug-in system with its different housing variants can also be used for signal plugs and data transmission. M23 power connectors are commonly used in servo drives, robotic systems, and automation systems where they provide power, control, and signal transmission in a single interface.

These multifunctional connectors are also essential in automation technology, where sensor technology plays a central role. Many sensors require special power connectors that not only transmit electrical energy, but also enable secure data communication while meeting high protection requirements.

CEE Plug

CEE connectors are designed to transmit high currents (from 16 A to 125 A) and high voltages (usually 230 V, 400 V or 1,000 V). They are primarily used in industrial applications where a strong and stable power supply is required.

CEE Plugs - Applications

CEE connectors or CEE connectors are specifically designed for industrial use. They are standardized according to IEC 60309 and feature color coding and a robust construction. IEC 60309 specifies that connectors must be available in different frame sizes and amperages to meet the varying requirements of industrial power supply. IEC 60309 defines connectors for nominal currents between 16 A and 125 A and for nominal voltages up to 1000 V.

In the industry, CEE plug-in devices are used primarily in areas where high currents and voltages are required to reliably supply power to machines and equipment. They are commonly used in production halls and manufacturing facilities, where they are used for powering industrial machinery, manufacturing lines and plant controls. They are also found in energy and plant engineering, where they supply power to transformers, control panels and distribution boxes.

CEE Plugs - Assignment and Coding

A special feature of the CEE plugs is their color coding, which allows easy identification of the voltage classes and phases. For example, the blue CEE plug is for 230 V (single-phase), the red CEE plug is for 400 V (three-phase), and the green CEE plug is for nominal operation at frequencies from 60 to 500 Hz. This color coding is an elementary safety aspect in addition to the different thicknesses of the contacts and is consistent with the general safety standards in mechanical engineering.

Another important part of the coding is the time position of the protective contact (PE). The protective conductor contact is characterized by a distinctive outer nose on the plug and a suitable recess on the socket. This physical guide ensures that the plug can only be inserted in the correct orientation. In addition, the protective conductor is thicker than the remaining contacts, so that it cannot be mechanically placed in an incorrect position. This ensures reverse polarity safety, and a faulty connection between live contacts of different plug-in systems is excluded.

Hybrid connector

Hybrid connectors or Hybrid connectors are a specialized form of power connectors that not only transmit electrical power but also control, signal, or data cables in a single connector. Hybrid connectors are commonly used in industrial automation, robotics, motion control and mechanical engineering, where compact, high-performance and trouble-free connections are required.

Benefits of Hybrid Connectors

One of the greatest advantages of hybrid connectors is their combination capability, as noted above, because they transmit not only electrical power but also control, signal or data cables in a single device. This greatly reduces space requirements by avoiding multiple separate plug-in connectors and wire harnesses, which in turn reduces the overall size and weight of machines or systems. It also simplifies installation and maintenance by requiring a single connector to cover various functions.

Another advantage is the reduction of cabling complexity. Since different types of signals (e.g. power, control and data) are integrated in a plug, cabling errors are minimized. This can reduce costs while increasing system reliability. In addition, many hybrid connectors also offer very high immunity to interference due to their design, as they shield the signals from each other. This is especially important in environments with electromagnetic interference (EMI).

Disadvantages of Hybrid Connectors

Despite these advantages, hybrid connectors also have some disadvantages. Because they combine multiple functions into one connector, they are typically more complex than traditional connectors. This can lead to longer manufacturing and procurement times. Integrating different signal types in a plug can also result in higher costs compared to simple connectors, especially when specialized materials or additional shielding is required.

Another drawback is that the flexibility in the configuration may be limited. In some applications, it may be beneficial to use separate connectors for different signal types to achieve greater adaptability and modularity. Finally, if the hybrid connector is damaged, multiple connection functions may be affected at the same time, which could lead to greater system failures than would be the case with separate connectors.

Insulation of Hybrid Connectors

Since hybrid plugs carry high currents for motors as well as sensitive data and control cables, special insulation and shielding are required to avoid interference from electrical fields and noise. The physical separation of high-current and low-voltage contacts, as well as the use of high-strength plastics with high dielectric strength, ensure safe insulation. In addition, a well-designed contact arrangement with power contacts placed in the center and signal contacts placed at the edge minimizes susceptibility to interference. In order to reduce electromagnetic influences, metal housings or metallized plastic housings are used, while separate ground and shield contacts dissipate high-frequency interference.