ProfiNet is driven by the largest Fieldbus Organization! Over 1200 vendors, including Pheonix (2nd Largest installed based). Total number of nodes including Pheonix = 16.5 million.
Profinet offers:-
PROFINET offers – as the only Ethernet-based system – Real-Time for synchronized Motion Control application while being fully open for all standard Ethernet services at the same time!
PROFINET offers high speed IO data exchange and seamless integration for existing fieldbus systems
PROFIBUS International today already offers PROFIsafe for PROFIBUS and starting in 2005 also for PROFINET
PROFINET is the most comprehensive standard including network management, security, etc.
Re-usage of modules (machines, machinery parts, parts of manufacturing lines) with PROFINET CBA reduces costs for the engineering and commissioning
Executive Summary
competition
Comparison
Overview of Ethernet systems
Modbus TCP
Pros / Cons
PROFINET represents a comprehensive Ethernet Standard for the automation world
PROFINET also comprises network management, security, network installation, motion control, safety, …
MODBUS-TCP is only an open Internet Draft Standard which relates only to communication
PROFINET is supported by the world's strongest umbrella organization and its many members
Support for Modbus TCP technology is available only through Internet links and discussion groups
No support from Schneider or Modbus-IDA
Siemens offers development kits & support (even on-site support)
PROFINET Competence Centers for certification already in place in Europe and the U.S.; Asia is next
Modbus TCP offers no concept for distributed applications
Currently it is not clear what role the IDP model will play for Modbus TCP
PROFINET offers a solution with Component based Automation
Re-use of technological machines and plant sections saves engineering and commissioning costs
PROFINET has separate workgroups for security and network management
Modbus TCP is showing no activities of any kind regarding these topics
Maximum size of an I/O useful data frame for Modbus TCP is only 248 bytes
For PROFINET, the maximum size of an I/O useful data frame is 3 times this size at 1,440 bytes
Larger data volumes can thus be transferred at one time
PROFINET enables real-time communication even when the network is congested thanks to ASICs (ERTEC inside)
MODBUS-TCP is not suitable for motion control applications
No high-performance or isochronous mode
A faster response time is possible with PROFINET
PROFINET: 2mS for 32 field devices with 1xDI/DO/AI/AO each. Must be verified through measurement tests.
Modbus TCP: 60 to 70ms for 32 field devices.
Poor performance strongly limits applications in machine and plant construction
Schneider currently has no solution for fail-safe applications
With PROFIsafe, PI established a market profile for fail-safe applications based on PROFIBUS
PROFIsafe is bus system-independent, allowing it to be used on PROFINET (in products beginning 2005)
Non-prioritized MODBUS-TCP messages
Network congestion also results in considerable fluctuations in IO "real-time data" communication, which is not very powerful to begin with
PROFINET enables real-time communication even in the face of network congestion thanks to the use of real-time switches (ERTEC inside).
Communication with PLCs from other manufacturers is impossible for Schneider via both TCP/IP native and FTP
SIMATIC CPs can communicate using both TCP/IP native and FTP
The integration of host devices is possible only when these devices support Modbus TCP
Momentum I/O are incapable of channel-specific diagnostics
Advantys STB, supposedly with channel diagnostics, was exhibited at SPS/IPC Drives 2003
SIMATIC provides comprehensive device diagnostics for field devices and switches (head interface module, module and channel diagnostics)
Device replacement is not possible without a programming device/PC
Manual matching in BOOTP server required
The replacement device must be given a role name
SIMATIC supports device replacement without programming device through MMC
Ethernet IP
Pros / Cons
Maximum size of an I/O useful data frame is only 500 bytes on EtherNet/IP
On PROFINET, the maximum size of an I/O useful data frame is three times that size at 1,440 bytes
Larger data volumes can be transferred at one time
Routing between EtherNet/IP and DeviceNet without a gateway
Results in enormous protocol overhead
PROFINET is pursuing high-performance proxy concept
Faster response times under PROFINET due to minimum protocol overhead
PROFINET – Siemens:
2mS for 32 field devices with 1xDI/DO/AI/AO.
Must be verified through measurement tests.
EtherNet/IP – Rockwell:
Approx. 20ms for 32 field devices with 1xDI/DO/AI/AO module (computed using worksheet for 1 CP).
PROFIBUS International has years of knowledge with Safety – the ODVA not.
CIP Safety won‘t be available in the near future
Today, not even a DeviceNet based solution
Real-time for motion control with Standard Ethernet hardware
EtherNet/IP wants to implement real-time via IEEE 1588
Even IEEE1588 and prioritization can't help when the network is congested, making them unsuitable for motion control applications and simultaneously unlimited IT traffic
PROFINET enables real-time communication even in the face of network congestion thanks to ASICs (ERTEC inside)
System barriers at Rockwell when SERCOS-III is used for motion control
PROFINET is an integrated system with applications for all sectors
Without PG/PC, device replacement is not possible
Manual matching in BOOTP server required
Siemens supports device replacement without programming device through MMC
At present, Rockwell can not implement fail-safe applications over a bus cable with ControlNet, DeviceNet or EtherNet/IP
With PROFIsafe, PI has already established a market profile for fail-safe applications based on PROFIBUS
PROFIsafe is bus system-independent, allowing it to also be used on the PROFINET (in products beginning in 2005)
With STEP 7, Siemens enables plant-wide engineering with consistency check
In RS Logix 5000, a separate project must be created for each PLC station. There is no cross-project consistency check.
Rockwell does not offer a solution for distributed applications
With Component-based Automation, PROFINET does offer a solution
Item Library (not changeable)
No re-use, no graphical engineering
With CIP only a common programming interface
The number of Ethernet interface modules in the ControlLogix must be calculated in advance using spreadsheets
In STEP7, the bus cycle time is computed and displayed automatically
Rockwell can communicate with PLCs from other manufacturers neither over TCP/IP native nor over FTP
The SIMATIC CPs make such communication possible over both TCP/IP native and FTP
Rockwell does not offer its own network components; so it has no well-defined network competence
Siemens has a broad range of active and passive network components (incl. Wireless) with support.
A faster response time is possible with PROFINET
PROFINET: 2ms for 32 field devices with 1xDI/DO/AI/AO each. Must be verified through measurement tests.
Ethernet IP: approx. 20ms for 32 field devices with 1xDI/DO/AI/AO module each (spreadsheet - for 1 CP).