Siemens C79000-Z7076-C552-01 Manuel D’Utilisation

New Functions in Version V4.02

8

Supplement to the STEP 7 User Manual V4.0

C79000-Z7076-C552-01

The configuration of a “warm standby” system consists of:

Two S7 stations with one PROFIBUS-DP master interface each (each of these
interfaces forms its own subnet).

One or more ET 200M devices with IM 153-3 which are connected to both
subnets.

This configuration ensures that the “standby station” takes over the processing of
the user program if one station (one of the two DP masters fails) fails.

DP Master 1

ET 200 M with IM 153-3

Two stations, each with one PROFIBUS-DP master interface

PROFIBUS

Station A

Station B

DP Master 2

To set up this configuration with STEP 7, proceed as follows:

1. Configure the first station (station A) with all the ET 200M devices (IM 153-3).

2. Configure the second station (station B) without I/Os.

3. Copy the ET 200M in station A and paste these DP slaves in the DP master

system of station B (menu command Edit 

 Redundant Paste); see also

Page 4 (Improved Copy Function).

In contrast to the “normal” Paste function, “Redundant Paste” preserves the
existing PROFIBUS and I/O addresses. Inconsistencies in addresses are thus
avoided. You should follow step 3 very carefully; if the addresses overlap, this
may cause the “Redundant Paste” to fail.

4. Complete the configuration of station B with central and distributed I/Os.

Important: The DP slaves with IM 153-3 must be configured in each of the two
stations, which means they appear as two separate objects, although they are
physically one and the same slave. If you change settings for one of the DP
slaves, you must also copy this modified DP slave to the other station again to
ensure consistency.