×
Siemens Industry Online Support
Siemens AG
Entry type: FAQ Entry ID: 51678187, Entry date: 10/24/2017
(7)
Rate

How do you set up the DP/PA link and how do you configure the DP/PA link and DP/PA coupler?

  • Entry
  • Associated product(s)
PROFIBUS PA master systems are connected to a PROFIBUS DP master system with a DP/PA link.

The DP/PA link comprises one or two IM153-2 interface modules and between one and a maximum of five DP/PA couplers.
The DP/PA link is connected to the PROFIBUS DP master system via the interface module. If you use two interface modules in the DP/PA link, you can connect the DP/PA link to a redundant PROFIBUS DP master system. The lower-level PROFIBUS PA field devices are connected to the DP/PA link via the DP/PA coupler, which means that

the DP/PA link creates a gateway from a PROFIBUS DP master system to a PROFIBUS PA master system.


Fig. 01

How the DP/PA link works

  • The DP/PA link is a DP slave on the higher-level DP master and acts as a proxy for the stations (PA field devices) which are connected to the lower-level bus system.
  • The DP/PA link forms an independent, lower-level bus system which is decoupled from the higher-level DP master system for communications technology reasons.
  • Multiple DP/PA couplers are used to increase the current carrying capacity of the PA master system.
  • All the DP/PA couplers of a DP/PA link form a shared bus system with the PA field devices which are connected.

Use a DP/PA link if you require a transmission rate greater than 45.45 Kbps on PROFIBUS DP. The DP/PA link resets the higher transmission rate of PROFIBUS DP on its backplane bus module to 45.45 Kbps and passes it on to the DP/PA coupler. You only configure the interface module of the DP/PA link. You can configure the DP/PA coupler to boost the system's diagnostics capability.

How the DP/PA coupler works
The DP/PA coupler is a physical link between PROFIBUS DP and PROFIBUS PA.

The DP/PA coupler can be operated in standalone mode without any other components. This enables the PROFIBUS PA field devices to be addressed via PROFIBUS DP.
The DP/PA coupler is used in standalone mode if PROFIBUS DP supports 45.45 Kbps and this is an adequate transmission rate.

Configuring the DP/PA coupler and DP/PA link
There are two ways of using the DP/PA coupler:

  1. The DP/PA coupler can be operated in standalone mode. In this case, it is not necessary to configure the DP/PA coupler in the Hardware Configuration. The PROFIBUS PA field devices can be configured directly on the PROFIBUS DP master system of the CPU.
    When you configure the DP/PA coupler, it is a station on the PROFIBUS DP master system and can be addressed by the DP master, which makes diagnostics of the system possible.


    Fig. 02

    In the Properties of the PROFIBUS DP master systems you select the "Network Settings" tab and set the transmission rate to 45.45 (31.25) kbps.


    Fig. 03
  2. The DP/PA coupler is operated on a DP/PA link. In this case, the IM153-2 interface module of the DP/PA link is configured in the Hardware Configuration. The IM153-2 interface module is located in the Hardware Catalog under "PROFIBUS-DP > DP/PA Link".


    Fig. 04

    Add the PA field devices to the PA master system of the IM153-2.


    Fig. 05

Note
In standalone mode, the DP/PA coupler FDC157-0 and the PROFIBUS PA field devices are configured directly on the PROFIBUS DP master system. If the DP/PA coupler FDC157-0 is operated on a DP/PA link, it is configured on the PROFIBUS PA. Configuring the DP/PA coupler FDC157-0 improves diagnostics.

Use of a DP/PA coupler pair and active field splitters facilitates redundant operation on a PROFIBUS PA master system in two variants:

  • Ring redundancy using the active field distributor (AFD)
  • Coupler redundancy using the active field splitter (AFS)

The "DP/PA Coupler, DP/PA Link and Y Link" manual provides detailed information about the separate components of the DP/PA link and about how to commission the DP/PA link. The manual is available for downloading in Entry ID 1142696.

Hardware components for configuring a DP/PA link
This entry includes an overview of the hardware components used to set up a DP/PA link.

1. Configuration without bus modules and power supply
 

Hardware component Article number
1 x IM153-2


  • 6ES7153-2BA70-0XB0 for extended temperature range
Bus connector -
Max. 5 DP/PA couplers
  • 6ES7157-0AC85-0XA0 or
  • 6ES7157-0AD82-0XA0 EX version EX(IA)

Table 1

2. Configuration with bus modules and power supply
 

Hardware component Article number
1 x IM153-2 6ES7153-2BA70-0XB0
1 x power supply PS 307 6ES7307-1...
1 x bus module PS/IM
for a power supply unit and an IM153-2
6ES7195-7HA00-0XA0
Max. 5 DP/PA couplers 6ES7157-0AC85-0XA0
Bus module DP/PA coupler
  • 6ES7195-7HF80-0XA0 or
  • 6ES7195-7HG80-0XA0
    for 2 DP/PA couplers (DP/PA coupler pair)

Table 2

3. Configuration with bus modules without power supply

Hardware component Article number
1 x IM153-2
  • 6ES7153-2BA70-0XB0 for extended temperature range
1 x bus module IM/IM
for an IM153-2
  • 6ES7195-7HD80-0XA0 for extended temperature range
Max. 5 DP/PA couplers
  • 6ES7157-0AC85-0XA0 or
  • 6ES7157-0AD82-0XA0 EX version EX(IA)
Bus module DP/PA coupler
  • 6ES7195-7HF80-0XA0 or
  • 6ES7195-7HG80-0XA0
    for 2 DP/PA couplers (DP/PA- coupler pair)

Table 3

Hardware components for configuring a redundant DP/PA link
This entry includes an overview of the hardware components used to set up a redundant DP/PA link.
 

Hardware component Article number
2 x IM153-2
  • 6ES7153-2BA70-0XB0 for extended temperature range
1 x bus module IM/IM
for an IM153-2
  • 6ES7195-7HD80-0XA0 for extended temperature range
Max. 5 DP/PA couplers
  • 6ES7157-0AC85-0XA0 or
  • 6ES7157-0AD82-0XA0 EX version EX(IA)
Bus module DP/PA coupler
  • 6ES7195-7HF80-0XA0 or
  • 6ES7195-7HG80-0XA0
    for 2 DP/PA couplers (DP/PA coupler pair)

Table 4

Note

  • If you wish to operate the PROFIBUS PA as redundant, you need two DP/PA couplers 6ES7157-0AC85-0XA0 (DP/PA coupler pair) and active field distributors (AFD) or active field splitters (AFS).
  • The interface module IM 153-2 with article number 6ES7153-2BA70-0XB0 supports the function "Extended field diagnostics (EFD)". This function and planned innovations in the PROFIBUS PA environment are supported only with this interface module.
  • The DP/PA couplers of the EX versions are not available in the Hardware Configuration because they do not have diagnostics capability. There is no provision for configuring these DP/PA couplers.

Further Information
More information about setting up a DP/PA link and the redundant configuration of a PROFIBUS PA is available in the following manuals and entries:

  • SIMATIC Bus Couplings DP/PA Link, Active Field Distributor, DP/PA Link and Y Link: 1142696
  • How do you configure a ring redundancy with FDC 157-0 DP/PA couplers and active field distributors (AFDs)?: 44887866
  • SIMATIC Bus link Extended fieldbus diagnostics in PROFIBUS PA: 88994694