wilamowski-b-m-irwin-j-d-industrial-communication-systems-2011

Profisafe 46-7
F-host
IO
controller
Intrinsic safety
(Ex-i)
With barriers: RS485-IS
e.g., for high speed ESD valves
Local bus
PN IO
PN IO/
DP
Link
RS485
DP-PA
Link
MBP-IS
Actuator
PA device
Remote I/O
F
D
I
F
D
O
D
evice
F-
Device
F
AI
PN IO
MBP-IS
RS485
F-DI
F-DO
F-AI
PA Device
PROFINET IO transmission
Data transmission for explosion-proof areas
High speed data transmission
Fail-safe digital input
Fail-safe digital output
Fail-safe analog input
Device according process automation device model (IEC 61804)
PA device model acc.
IEC 61804:
- Physical block
- Function block(s)
- Transducer block
FIGURE 46.10 Profisafe is protocol-independent. (Adapted from Stripf, W. and Barthel, H., Comprehensive
safety with PROFIBUS DP and PROFINET IO—Training for “PROFIsafe certified designers.”)
Normal
I/O data
Normal
I/O data
Normal
I/O data
Safety
I/O data
Normal
I/O data
Normal
I/O data
F-input/output data
Control/status
byte
CRC2
Maximum 12/123 octets 1 octet 3/4 octets
FIGURE 46.11
General safety data format.
46.2.5 Virtual Consecutive Number
Only the V2-mode (virtual) consecutive number will be described here. For a description of the V1-mode,
see [9]. The consecutive numbering uses a range that is big enough to detect any error caused by message
storing network elements, e.g., switches for Profinet, links or repeaters for Profibus. The receiver uses
the consecutive number to monitor whether the sender and the communication channel are still alive.
© 2011 by Taylor and Francis Group, LLC