Profibus Cable & Profibus Connectors Tricks & Tips

A Profibus cable and Profibus connectors are widely described as the world’s leading fieldbus cable and connectors. Profibus is thus basically a standard for fieldbus communication in automation technology; an industrial control network used for factory automation, process control, motion control, and safety networks.

Must Read :What is Profibus ? How Profibus Work ?

A Profibus cable and Profibus connectors produce significant cost savings regarding design, installation, and maintenance expenses.

Profibus (Process Fieldbus) is an international fieldbus communications standard for linking process control and plant automation modules.

Must Read : Profibus DP and PA : It’s Not as Difficult as You Think

Instead of running individual cables from a main controller to each sensor and actuator,

a single multi-drop cable is used to connect all devices, with high speed, bi-directional, serial messaging used for transfers of information.

Origin of Profibus Cable and Profibus Connectors

Profibus cable and Profibus connectors owe their existence to the need to implement and spread the use of a bit-serial fieldbus based on the basic requirements of the field device interfaces.

First, the complex communication protocol Profibus FMS (Fieldbus Message Specification) was specified.

Later on, the specification for the simpler and thus considerably faster protocol Profibus DP (Decentralized Peripherals) was completed. It replaced FMS.

Benefits of using a Profibus Cable and Profibus Connectors

Using a Profibus cable and Profibus connectors offer huge savings on cabling costs when compared with older methods.

Profibus cable and Profibus connectors allow for simple linking of devices from many different vendors and can even reduce installation, commissioning, fault-finding, and associated plant downtime costs.

Characteristics of Profibus Cable and Profibus Connectors

Some characteristics associated with a Profibus cable and Profibus connectors include reducing operating costs, increasing productivity, decreasing time to market for new products, and improving product quality.

Unlike a standard fieldbus cable and connectors, a Profibus cable and Profibus connectors can support up to 32 devices per segment, which means up to a total of 126 devices, depending on total system current.

Must Read :Profibus vs Profinet (Difference between Profibus and Profinet)

What are the different Profibus Cable and Profibus Connectors variants?

Two variations of Profibus cable and Profibus connectors are available on the market today: the most commonly used Profibus DP, and the lesser used Profibus PA variations.

Profibus DP (Decentralized Peripherals)

This variation Profibus cable and Profibus connectors are used to operate sensors and actuators with the help of a centralized controller in production technology.

The many standard diagnostic options, in particular, are focused on here. Other areas of use include the connection of “distributed intelligence”, i.e. the networking of multiple controllers to one another (similar to Profibus FMS).

Data rates up to12 Mbit/s on twisted pair cables and/or fiber optics are possible.

Must Read : Profibus vs Modbus (Difference between Profibus and Modbus)

Profibus PA (Process Automation)

This Profibus cable and Profibus connectors variant is used to monitor measuring equipment via a process control system in process engineering.

It is ideal for explosion-hazardous areas. Here, a weak current flows through bus lines in an intrinsically safe circuit so that explosive sparks are not created, even if a malfunction occurs. The disadvantage of this variation Profibus cable and Profibus connectors are the slower data transmission rate of 31.25 kbit/s.

A Profibus cable and Profibus connectors are the only fieldbus cable and connectors that can be used in equal measure in production automation and process automation and has since become a leader in the global market. It is estimated that more than 20 million Profibus cable and Profibus connectors are in use worldwide (as of 2007).

Neither Profibus DP nor Profibus PA should be confused with ProfiNet, which is a totally different Ethernet based communications standard used for process measurement and control over Cat 5 (or similar) twisted pair cables, as most frequently seen for linking office computers.

Should there be distance between a Profibus Cable/Profibus Connectors and Power Cables?

There should always be distance between Profibus cable/Profibus connectors and any other power cables.

Even a Profibus cable and Profibus connectors can get disturbed by interference caused by parallel high voltage power lines.

One should always try to have at least 10 cm air space between the Profibus cable/Profibus connectors and power cables (depending on the level of the voltage).

Some people mix Profibus cables/Profibus connectors and power cables in one cable tray and that often leads to unreliable behaviour. However, Profibus cables/Profibus connectors and power cables that cross each other will not cause problems.

Creating distance is not the only requirement; correct shielding is also a must.

Final words & Tips about Profibus Cable and Connectors

  • Always use a Profibus cable and Profibus connectors;
  • Do not exceed 32 devices per segment (including repeaters, OLMs and couplers);
  • Ensure the segment length is in contrast with the baud rate;
  • Ensure every segment has powered termination on both ends;
  • Avoid spur lines;
  • Avoid swapping the wires (A=green, B=red); and
  • Mark how long the cables really are and update the drawings.

After installation you should test your work:

  • Are the addresses correctly set?
  • No short circuit or break in the cable?
  • Are you able to communicate with the devices?

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