5-3
Communications Processor CP 541
EWA 4NEB 812 6188-02
5.1.1
Safety-Related PLC-PLC Connection
The safety-related PLC-PLC connection serves for message-oriented commu-
nication between two failsafe programmable controllers, without a detour via
an additional station.
Each message of the safety-related PLC-PLC connection can contain up to
60 bytes of net data, plus 4 bytes for data detection and correction.
When you install a PLC-PLC connection, the CP 541 must be programmed
as the active station.
The node address specified in the programmable controller is converted by
the CP 541 to the station number and vice versa. Node address 1 is converted
to station number 1, node address 2 to station number 2, etc.
AG
CP
541
1
30
3
2
1
30
3
2
SINEC L2
Figure 5-1 Address Conversion for the Safety-Related PLC-PLC Connection
Node addresses 1 to 30 are available for the PLC-PLC connection in the con-
nected programmable controller.
You assign parameters for the safety-related PLC-PLC connection in the con-
nected failsafe programmable controller as for a SINEC L1 slave with
COM 95F or COM 115F.
With the S5-95F, you can install two safety-related data paths in message
mode 115F-15. The S5-115F allows 29 safety-related data paths. Message
mode 95F is not permissible.
Introduction
Message Length
Active Station
Address
Conversion
Address Range
Parameter
Assignment
Data Paths
CP 541 with S5-95F/S5-115F