Noticias de Aplicación: Tendencias en la transmisión de la energía

Mechanical and plant engineers are implementing distributed I/O equipment and functions across standardized interfaces. They aim to revolutionize conventional installation technology, while reducing costs.

With conventional wiring, the transfer of signals and energy is arranged in a star-shaped pattern. In actual practice, this means connecting each drive with electrical power from the switch cabinet. The connections for sensors and actuators (e.g. proximity switches or valves) are also wired in parallel.

Wiring technology was revolutionized by connecting sensors and actuators via serial bus modules. New installation methods have been developed for data transfer, considerably simplifying cable runs in customer equipment. Protection classes IP 20 to IP 68 provide specifications for existing signal modules which receive and output control signals. There have been virtually no changes in the way small drives (up to approx. 2.2 kW) are powered.

Each drive is still powered via a separate cable from the switch cabinet. Switch cabinets with centralized drive control contain the following components:

• Fused power line

• Central control unit with protective devices, such as

• direct starter

• reversing starter

• soft starter

• frequency inverter

• Cable to the drive, using terminal strips or connectors

Conventional installation technology is too expensive and will be modified, for instance in materials handling technology. The trend is towards distributed installation technology. This includes the distribution of intelligent drive controllers, directly on the machine or material-handling line. HARTING has taken on the challenge of changes in installation technology.

HARTING's approach
Initially, HARTING decided to find out what customers need. The company aims to combine forces in forging a new installation design philosophy for industry.

A major need is for an energy bus system to connect multiple loads to a single cable bus. Any new installation technology must, of course, adhere to national and international standards. Our work has shown that existing, standardized interfaces must be used. As a compact connector which features the required number of poles, voltage and current-carrying capacity, the Han connector plays a key role in developing energy bus systems. Our market analysis has also shown that connections have to be made without special tools.

Here are some of the requirements:

• The technology must be suitable for use with the standard industrial 230/400 V power system in accordance with VDE, or the 600 V system, in accordance with UL

• Ability to connect up to 7 conductors

• Wire cross-section of 4 mm²

• Uninterrupted energy bus line

• Connections must be made with standard tools

• IP 65 protection class

• Supply module, connection module, final element

• HARTING quality

Based on these requirements, we created an entirely new line of connectors.
The Han-Power® series

The Han-Power products and standard product series fulfill all requirements.

These new product series can be used when replacing the protective devices in a system.

A new switch cabinet for distributed installation technology will be considerably smaller, permitting space in a production facility to be used more effectively.

Remaining elements:

• Protective devices, such as power circuit breakers for preventing short circuits

• Supply element for the energy bus line, via a connector

Distributed energy distribution is designed as follows, depending on customer requirements.

Variant 1
The power supply cable is terminated with a Han Q 8/0 connector for up to seven cores, each with a maximum cross-section of 4 mm². The location of the distributed drive control is insignificant when running the energy line. A Han-Power S is used for the T-element, preventing the energy line from being interrupted.

Approximately 12 cm of the energy cable are stripped for the Han-Power S T-element. The wires are still completely surrounded by insulation and are placed in the insulation displacement connector. Screws ensure that a good connection is made and cut the insulation. The insulation displacement connectors are only loaded by the current which flows to the distributed "load".

Future manufacturing and material-handling systems will feature distributed components. Existing plants will be modified and equipped with distributed components. The trial run and function test are performed where the equipment will be operated, when plant is finished being constructed.

How does this installation design philosophy apply to systems consisting of individual modules, built and tested at the plant engineering firm?

Also, it must be considered that a production line is divided into a number of modules for shipping. The electrical installation must remain in place to utilize the advantages of the function test and avoid wiring errors if the system has been tested. There is no sense in rerunning an energy line.

In this case the savings are lost. The requirements for an uninterruptible energy bus line would seem to be different. Plant owners want to utilize all of the advantages of distributed installation technology. Variant 2 is one solution.

Variant 2
Here, an uninterruptible energy bus line is not required. The electrical power is supplied via a Han connector, as with Variant 1. The energy line is run directly to the drive control unit. The distributed control unit is connected via a HARTING connector, preferably the Han Q 8/0.

The advantages of this approach are obvious. The drive starter can be replaced if it fails. For instance, a drive starter can be changed quickly from a direct starter to a soft starter. Plant downtimes are brief, minimizing production losses. A further system module can be connected via a Han-Power S. The energy line is stripped, and the wires are placed in the insulation displacement connector. The prewired Han-Power S is the simplest way to create a T-element.

The system can be expanded with both variants. Of course, technical parameters must be taken into consideration, such as the maximum current-carrying capacity.

Han-Power S is thus the installation design philosophy of the future. It is one of the HARTING products and components which support future-oriented installation technology.