PROFIBUS Cables: The Cornerstone Ensuring Stable Operation of Existing Automation Systems

In the field of industrial automation, the stability of communication networks is directly linked to production efficiency and operational costs. Although new technologies like PROFINET are becoming increasingly prevalent, PROFIBUS, as a classic fieldbus protocol, continues to play an irreplaceable role globally—particularly in process industries and traditional manufacturing—thanks to its mature and stable characteristics.

However, in complex industrial field environments, many PROFIBUS networks fail to fully achieve their theoretical performance. The root cause often lies not in the controllers or instruments themselves, but in the "neural network" connecting the entire system—the PROFIBUS communication cable. Inadequate shielding effectiveness can make signals susceptible to electromagnetic interference; lack of flexibility can lead to broken conductors in dynamic applications like drag chains; and jacket materials unable to resist oil, chemicals, or extreme temperatures can result in difficult-to-troubleshoot communication interruptions, data fluctuations, increased maintenance frequency, and threats to production continuity.

Therefore, selecting a reliable cable for the vast existing scale of PROFIBUS systems is key to ensuring stable production and controlling long-term comprehensive costs. This article will systematically analyze the core elements of PROFIBUS cables and introduce how to select suitable solutions for different application scenarios.

Overview of Fieldbus and PROFIBUS

Fieldbus emerged in the early 1990s as a digital communication technology specifically designed for industrial environments. It primarily addresses data exchange between intelligent field devices (such as instruments, controllers, actuators) and information transmission between these devices and higher-level control systems. Within this technological scope, PROFIBUS (an acronym for Process Field Bus) is one of the earliest fieldbus protocols applied in industrial automation in Europe. As a bus solution primarily promoted by Siemens in the industrial automation field, it supports high-speed data transmission and is renowned for its excellent real-time performance and stability. Consequently, it is widely used in industrial automation sectors with high system performance requirements, such as process control, manufacturing, and metallurgy. PROFIBUS cables are mainly divided into two types:

· PROFIBUS-DP: Used in factory automation, featuring high-speed communication and a master-slave architecture. It is commonly used to connect PLCs, frequency converters, remote I/O modules, and other devices.

· PROFIBUS-PA: Suitable for process automation, supporting intrinsic safety and bus powering. It is specifically designed for connecting field instruments (e.g., pressure/temperature transmitters) and is commonly found in hazardous areas with explosion-proof requirements, such as chemical and petroleum industries.

Currently, PROFIBUS cables remains widely used in numerous industries including chemicals, pharmaceuticals, food and beverage, and automotive manufacturing.

PROFIBUS Cables Explained: How Performance Determines System Stability

As the physical layer foundation of a PROFIBUS network, the performance of the cable is key to determining the overall communication quality of the system. It primarily influences stability through the following aspects:

· Signal Integrity: Precise characteristic impedance (e.g., 150Ω) and an effective shielding layer (e.g., aluminum foil wrapping plus tinned copper braiding) are the foundation for resisting external electromagnetic interference and ensuring lossless signal transmission.

· Mechanical Reliability: In scenarios requiring continuous movement, such as drag chains and robots, the cable's flex life (e.g., millions of bending cycles) and small bending radius are crucial for minimizing failure risk and ensuring long-term stable operation of the automation system.

· Environmental Adaptability: The jacket material (e.g., PVC, PUR) directly determines the cable's resistance to oil, corrosion, hydrolysis, and flammability, enabling the cable to adapt to harsh industrial environments involving high temperatures, oil contamination, chemicals, etc.

Zhaolong PROFIBUS Cable Solutions: Designed for Stable Operation

To address the stringent requirements of different industrial scenarios, Zhaolong offers a complete PROFIBUS cable product matrix, ensuring precise system design matching and long-term reliability.

01. Zhaolong PROFIBUS-DP Cable (Fixed Installation)

· Positioning: A cost-effective solution for fixed installation.

· Core Advantages:

a. Stable Transmission: 150±15Ω characteristic impedance precisely matches PROFIBUS-DP requirements; aluminum foil + tinned copper braid double shielding ensures excellent resistance to external electromagnetic interference.

b. Safe and Reliable: Cable flame retardancy meets IEC 60332-1-2 requirements; the jacket offers PVC and Low Smoke Zero Halogen (LSZH) options.

c. Environmental Adaptation: Products are available to meet different temperature range requirements, for example: PROFIBUS-DP cables for -20°C to 70°C or -40°C to 80°C.

d. Typical Applications: Strictly complies with fieldbus standards and PROFIBUS-DP requirements; suitable for all industrial fieldbus systems requiring high reliability and fixed installation, e.g., connections between fixed control cabinets and field devices (sensors, actuators, instruments), deployment of communication networks for factory automation infrastructure.

Zhaolong PROFIBUS-DP Cable

02. Zhaolong PROFIBUS-DP FD Cable (Flexible Drag Chain)*

· Positioning: A flexibility expert designed for continuous motion scenarios.

· Core Advantages:

a. High Flexibility and Bend Resistance: PROFIBUS-DP FD cable with PUR jacket meets requirements for at least 5 million drag chain cycle tests; minimum bending radius can reach 10 times the cable outer diameter (for moving applications).

b. Robust Protection: Optional PVC and PUR jackets; the PUR jacket is particularly resistant to oil, abrasion, and hydrolysis, suitable for harsh industrial mechanical motion environments.

c. Typical Applications: Strictly complies with fieldbus standards and PROFIBUS-DP FD requirements; suitable for all industrial fieldbus systems requiring highly flexible installation, e.g., power drag chain systems for automated equipment, moving parts of machinery (like machine tool spindles), robots (assembly arms), and other occasions with high requirements for flexible installation.

Zhaolong PROFIBUS-DP FD Cable

03. Zhaolong PROFIBUS-PA Cable (Process Automation)

· Positioning: An economical solution for process automation and explosion-proof areas.

· Core Advantages:

a. Intrinsic Safety Support: Designed complies with fieldbus standards and PROFIBUS-PA requirements; suitable for process automation and hazardous areas with explosion-proof requirements such as chemical and petroleum industries.

b. Safety and Environmental Protection: Zhaolong PROFIBUS-PA cables provide the ones with PVC or LSZH jackets, meeting IEC 60332-1-2 flame retardancy requirements.

c. Typical Applications: Connecting process instruments (pressure/temperature transmitters) in industries like chemicals, petroleum, and pharmaceuticals.

Zhaolong PROFIBUS-PA Cable

Choosing Professional PROFIBUS Cables: Investing in Long-Term Stability

Selecting a high-quality PROFIBUS cable is a wise investment from the perspective of the equipment's entire lifecycle—its excellent electrical and mechanical performance not only reduces unplanned downtime caused by communication interruptions, ensuring production continuity and capacity, but also lowers daily maintenance and replacement costs, effectively controlling long-term comprehensive operating expenses.

Zhaolong PROFIBUS cables are precisely such a reliable choice: we are committed to providing a stable and reliable connection foundation for automation systems.

Currently, the vast majority of our industrial cables and connectors (including the LONGTRONIC® series PROFIBUS cables) have been integrated into the EPLAN Data Portal. You can directly call up accurate product models and full parameter data in the EPLAN platform, and efficiently select models based on key attributes such as voltage rating, shielding type, jacket material (PVC/LSZH/PUR), and temperature/bending radius, thereby enhancing system design reliability from the source. For further information, please follow us to gain industry knowledge and solutions, or visit the Zhaolong official website to download detailed technical documentation. You can also directly contact our technical engineers for free one-on-one selection support and sample applications.