1/31/2010 2:02 AM | |
Joined: 7/2/2008 Last visit: 9/25/2024 Posts: 928 Rating: (308)
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Hello Raed, Maybe you should think seriously why you need redundant controllers. You already have an installation which doesn't have redundant controllers for sure since it's a Profinet network. So, why would you like to increase controllers availability? Why not IMs?Why not I/O modules?
I'll try tomake it simple. The interface module should be intelligent enough to, 1- Identify the current master controller. 2- Disregard coming telegrams from reserve controller. 3- Switch over between the 2communication channelsin event of controller failure. The Red. bundle (two IM153-2 HF with an IM/IM Bus module)is the only interface module(s) in Siemens portfolio that can switch over from one communication channel (DP port) to the other communication channel (DP port) according to which CPU is currently the master. Any Profinet IM still doesn't have this mechanism (i.e. having two communicationto 2 controllerswith the ability to switch between them). To understand more about S7-400H system, you should read the S7-400H manual specially Chapter 10 (Using I/Os in S7-400H). Best regards. H-H |
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2/3/2010 10:28 AM | |
Posts: 96 Rating: (7) |
Dear Interested, See this Post for a solution بالتوفيق |
Last edited by: Raednabeel at: 2/3/2010 10:29 AM |
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2/3/2010 11:52 PM | |
Joined: 7/2/2008 Last visit: 9/25/2024 Posts: 928 Rating: (308)
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Hello Raed,I still recommend to make things easy andwork withY-Link. However, you can use PN CPUs and link them to H system through S7 connections. I hope you have checkedChapter 11 in S7-400H manual (Checkattachment).
I didn't have the chance to do it but it should work. It will just require more programming and more attention for distributingcontrol tasks between the PN CPUs. Your control philosophybecomes vague to me. Do you want the remote stations to depend on S7-400H? Why don't you use a single CPU with PN I/O controller and connect this CPU to S7-400H (Which controls Profibus slaves) instead of having many PN CPUs?
To the best of my knowledge this is not possible.
Best regards. H-H AttachmentS7_400_H_S7_Connecion.pdf (406 Downloads) |
2/4/2010 10:55 AM | |
Posts: 96 Rating: (7) |
I have to tell you that I am not responsible for the design and why things is designed by this way, my mission is to deal with the existed design, if I reached the dead end , the design will be changed
Yes I want the remote stations depends totally on S7-400H. By using Single CPU with PN/IO controller , the risk of lost the communication with the other profinet stations will be very high. isn't that ?
I meant with IO data not the direct access to IO modules in the profinet station but the IO area at the CPU "IM 154-8 PN/DP CPU" you can see this post
I think by using "IM 154-8 PN/DP CPU" MY S7-400H station will deal with profinet stations as S7-300 stations via S7 connections over industrial ethernet, hence the profinet IO functionality dose not concerned me. Any way H-H, I am very very grateful for your support and posts, when we reache the implementation stage, I will tell you about evolvments. "if we still alive" , In unofficial arabic language : إذا ظلينا عايشيين BR |
Last edited by: Raednabeel at: 2/4/2010 11:00 AMLast edited by: Raednabeel at: 2/4/2010 10:56 AM |
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2/6/2010 10:58 PM | |
Joined: 7/2/2008 Last visit: 9/25/2024 Posts: 928 Rating: (308)
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Hello Raed,
Ithappens to me sometimes, to work with a configurationthat's notmine but I always highlight the weak pointsin system design.
I can't say it's very high. It should be calculated first. It depends on MTBF (Mean Time Between Failures)of this middle system (Controller and power supply).
Here we come to a major design aspect. I've quoted some meaningful words from Dorftrottel's post in this thread. Maybe the thread is not related to what we have here but I consider what Dorftrottelhad said is related to your system configuration somehow.
Now I want you to think again specially that you have chosenCPU 412-3H which can afford max. of 16 connections (One is always for PG and at least one for OP). Now,somequestions jumps to my mind. Did you think about your I/O update time? Scan cycle?Communication load? Online modifications? I don't want to disappoint youbut I justwant you to be aware of all difficulties you mayface in this configuration.
Yes, then I don't think thatyou can useSFC14 and SFC15 (They are used with DP slaves or PN I/O devices)
It's a pleasure to discuss this configuration with you. you are always welcome. I wish you luck in you project and don't forget to tell us how things work in your project. Best regards. H-H |
2/7/2010 10:58 AM | |
Posts: 96 Rating: (7) |
About the max connections for the CPU 412-3H is 16 , I don't uderstand it well. so: Is it mean the total devices that are connected to the cpu, even if I don't use S7-connections with them or the devices are connected via CP ? I have 18 DP slave connected to each other via optical ring , and then connected to the DP port on the CPU ? Also I have 6 "IM 154-8 PN/DP CPU" and 2 x-stations connected through ethernet optical ring then to scalance then to CP. So do I have 26 connections ? |
Last edited by: Raednabeel at: 2/7/2010 11:00 AMLast edited by: Raednabeel at: 2/7/2010 10:59 AM |
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2/8/2010 1:00 AM | |
Joined: 7/2/2008 Last visit: 9/25/2024 Posts: 928 Rating: (308)
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Hello Raed,
You can find more info on update and cycle time in chapter 16 (S7-400 cycle and response times)in S7-400H manual. What you can read there is definitely useful butwill not be suitable for your configuration because your I/O update time will depend on communication speed between the 2 CPUs (S7400H and S7-300) and cycle time of the 2 CPUs as well. I don't know how to even estimate it.
It should never disappoint you and you should take it as a motive to read more and ask more then you can learn more and more. No one knows everything and and no one wasbornknowing how to play with S7-400. Just give yourself the chance to learn and I must confess that I was happy seeing you asking how to reach infos in this website and I'm pleased that you could get to some manuals about communication yourself(It took me months to get used to this massive site).
Yes and NO. 21.8 is about writing data to a remote CPU using SFB/FB 15 ''PUT". 21.9 is aboutreading datafrom a remote CPU using SFB/FB 14 ''GET". So, Yes you can use these SFBs and FBs but you were asking about totally different things, SFC 14 DPRD_DATRead Consistent Data of a Standard DP Slave / PN IO device. SFC 15 DPWR_DATWrite Consistent Data to aStandard DP Slave / PN IO device. So, NO you can't use these SFCs.
I've extracted the following from SIMATIC Manager help.
If you go back to technical specifications where it's stated that the max. is 16 connections, you can find what kind of connections they mean (e.g. S7 communication, S7 basic communication,..etc.) So, only the 6 PN CPUs and the 2 X-Stations will be counted under connections. What are the X-Stations? Are they S7 CPUs? Don't forget one connection is always there for PG and at least one for OP communication. Best regards. H-H |
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