This catalog is out of date, see note on page 3

Process I/Os

PROFIBUS-PA

Connecting PROFIBUS-PA to AS 488/TM

■Design

Connection of PROFIBUS-PA using DP/PA coupler

The PROFIBUS-DP is connected to the AS 488/TM via an IF 964-DP interface module which can be plugged into an EXM 478 extension module.

DP/PA couplers are available in two versions: an Ex version with max. 100 mA output current and a non-Ex version with 400 mA output current. The DP/PA couplers are mounted together with a load power supply for DC 24 V on an S7-300 rail outside the haz- ardous area. A 9-pin Sub-D plug is used for connection to the

PROFIBUS-DP.

Four screw terminals are available for the PROFIBUS-PA con- nection with the non-Ex version. The PROFIBUS-PA cable can be looped through if required, or terminated by a selectable re- sistor. With the intrinsically-safe Ex version, the DP/PA coupler is always at the end of the cable, and the terminating resistor is ac- tivated. Only two screw terminals are available for the PROFIBUS-PA connection.

Each PA field device occupies a PROFIBUS address on the DP line.

Connection of PROFIBUS-PA using DP/PA link

The PROFIBUS-DP is connected to the AS 488/TM via an IF 964- DP interface module which can be plugged into an EXM 478 ex- tension module.

■Mode of operation

Users have access to the field devices on the PROFIBUS-PA using downloadable PA driver blocks which are combined in a driver library. These driver blocks support the cyclic services of the PA profile, and permit productive operation of a large num- ber of PA field devices from various vendors (e.g. Siemens, Endress+Hauser, Bürkert, Krohne, VEGA, NELES, etc.) which comply with this PA profile.

Limitation:

When linking PA field devices via the DP/PA link, the DP device must accept parameterization telegrams with a length of

10 byte.

Driver block

Description

PAAI

Analog input block for

 

PROFIBUS-PA

 

(representative of transmitter)

 

 

PAAO

Analog output block for

 

PROFIBUS-PA

 

(representative of actuators such

 

as drives, controllers etc.)

 

 

PADI

Discrete value input block for

 

PROFIBUS-PA

 

 

PADO

Discrete value block for

 

PROFIBUS-PA

 

(representative of actuators such

 

as valves etc.)

The DP/PA link comprises the IM 157 interface module and up to

5DP/PA couplers which are connected together via S7-300 standard bus plugs. By combination of the IM 157 with Ex or non-Ex versions of the DP/PA coupler, DP/PA link versions can be generated for use in hazardous and non-hazardous areas. The DP/PA link is mounted together with a load power supply for DC 24 V on an S7-300 rail outside the hazardous area. A 9-pin Sub-D plug on the IM 157 interface module is used for connec- tion to the PROFIBUS-DP.

Four screw terminals are available on the DP/AP couplers of the non-Ex version for the PROFIBUS-PA connection. The PROFIBUS-PA cable can be looped through if required, or ter- minated by a selectable resistor. With the intrinsically-safe

Ex version, the DP/PA coupler is always at the end of the cable, and the terminating resistor is activated. Only two screw termi- nals are available for the PROFIBUS-PA connection.

Only the DP/PA links occupy a PROFIBUS address on the

DP line. Each DP/PA link provides a separate address range for each of the subordinate PA field devices.

The communications interface permits operation of the PROFIBUS-PA on the AS 488/TM, and thus also the coexistence of additional masters of class 2 on the PROFIBUS-DP, setting of

45.45kbit/s as the transmission rate, as well as higher transmis- sion rates up to 12 Mbit/s.

8/18

Siemens PLT 112 · 2002

Page 78 Page 80
Page 79
Image 79
Siemens AS 488/TM Connection of PROFIBUS-PA using DP/PA coupler, Connection of PROFIBUS-PA using DP/PA link, Profibus-Pa
Page 78 Page 80

AS 488/TM specifications

The Siemens AS 488/TM is a cutting-edge solution in the realm of industrial automation and control. Designed specifically for high-performance applications, this device serves as a programmable logic controller (PLC) offering enhanced capabilities for process automation. The AS 488/TM stands out in the marketplace for its robust architecture, sophisticated features, and compatibility with various industrial protocols.

One of the pivotal features of the Siemens AS 488/TM is its integrated communication capabilities. It supports multiple communication protocols, such as Profibus, Profinet, and Ethernet/IP, facilitating seamless integration within diverse industrial environments. This flexibility ensures that the AS 488/TM can communicate with various devices, sensors, and actuators, providing a comprehensive solution for modern manufacturing needs.

In terms of processing power, the AS 488/TM is equipped with a high-performance CPU that can handle complex algorithms and data processing with ease. This enables the controller to manage intricate automation tasks, from simple control functions to complex multi-axis motion control. The device also comes with expandable I/O options, allowing users to tailor the system to meet specific application requirements. With a wide range of digital and analog inputs and outputs, the AS 488/TM ensures accurate monitoring and control of various processes.

Another notable characteristic of the AS 488/TM is its user-friendly programming interface. Siemens has developed the TIA Portal (Totally Integrated Automation Portal), a software platform that simplifies the programming and configuration of the PLC. This intuitive interface allows users to program the device using various programming languages, including Ladder Logic, Function Block Diagram, and Structured Text. The TIA Portal enhances productivity by providing simulation tools for testing and debugging applications before deployment.

The AS 488/TM also emphasizes safety and reliability. It complies with international safety standards and incorporates features that ensure safe operation in critical applications. Redundant power supplies and fail-safe mechanisms are integrated to minimize downtime and protect both personnel and equipment.

Moreover, the Siemens AS 488/TM is designed with future scalability in mind. As industries evolve and technology advances, the AS 488/TM can adapt to new requirements, ensuring a long service life and ongoing relevance in a rapidly changing landscape. Overall, the Siemens AS 488/TM is an impressive PLC that combines innovative features, robust technology, and flexible integration capabilities, making it an ideal choice for modern industrial automation systems.
Top Page Image Contents