5/25/2011 5:23 PM | |
Posts: 947 Rating: (45) |
I like ET200S. It has good set of functional modules, is more maintainable in the breakdown of a single entry. Modules are replaced quickly. Can be hot replaced ()hot-swap). For the H-system I'm using Y-Link. For my system it is enough. Splitted from what s benefit of using s7 400 IO cards instead of s7 300 IO cards?. |
Last edited by: O_Moderator at: 5/31/2011 8:42 AMnew subject after splitting |
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5/27/2011 6:16 AM | |
Joined: 10/7/2005 Last visit: 9/24/2024 Posts: 3022 Rating: (1054)
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Hello Aret not too sure why you dislike the Y-link, butcan tell you that your assumption concerning the internal workings of it is not quite correct. What the Y-Link does is to create a new "underlying" DP Master network which is independent of the higher level redundant DP Master system (see also "How is the Y-Link structured" for more). If you wish, you could even setthe underlying DP Master baudrate (and/or other DP related Parameters) to any value that you wish irrespective of the settings for the higher level redundant DP Master system. The tranfser of databetween the underlying IM197 based DP Master system and the higher level redundant IM153-2's DP takes place at the speed of the underlying DP Master (ok, this is an assumption on my behalf and I can't verify this at the moment). I wonder if your assumption comes from the fact that a Y-Link is initially "dragged" into the HWconfig from the"DP/PA link" catalogue as well as the generalfunctionality of a DP/PA link. If aDP/PA link is used,the underlying "PA" systemdoes infact run at a fixedspeedof"only" 45.45 kbps on the backplane(to whichthe IM157 PA couplers are connected). This is ok though as PA is fixed to run at31.25 kbps, the PA couplers do no more (and no less) than convert the 45.45kbps RS485 backplane DP signal to a 31.25 kbps MBP (Manchester bus powered)PA signal. |
Last edited by: fritz at: 5/27/2011 6:18 AMfixed link Cheers |
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5/28/2011 9:20 AM | |
Joined: 5/24/2007 Last visit: 4/24/2024 Posts: 284 Rating: (27) |
Hi Aret Have a look at the following link. http://support.automation.siemens.com/WW/view/en/43688632 Also at the documentation for Y-Link in that link. The restriction for the I/Os come from the IM153-2 which handles only 244byte I/O Frame. Krish |
5/28/2011 2:20 PM | |
Joined: 10/7/2005 Last visit: 9/24/2024 Posts: 3022 Rating: (1054)
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Just to be clear, the 244 Byte "restriction" is a limit that is NOT IM153-2 or Siemens imposed. Instead, it is simply the maximum amount of cyclic I/O data that a DP Slave can have asperProfibus Standard. |
Cheers |
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