5/27/2007 12:12 PM | |
Joined: 1/7/2006 Last visit: 11/17/2023 Posts: 2705 Rating: (315)
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Hi Begho, With which protocol is that protection relay working ? I have found the next text on Internet via Google: Modbus communication enables Sepam to be connected to a remote monitoring and control system equipped with a master Modbus communication channel and a physical link of the RS 485 type, or another interface equipped with an appropriate converter.The Modbus protocol used by Sepam is a compatible sub-group (Jbus) of the RTU Modbus (1) protocol (a Modbus master can communicate with several Sepam units). Sepam is always a slave station. |
I hope that the answer will help, if you have still questions, don't hesitate to ask me. |
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5/28/2007 12:48 PM | |
Joined: 1/7/2006 Last visit: 11/17/2023 Posts: 2705 Rating: (315)
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Hi Begho, On your questions the next answers: 1. Perfect. 2. The Modbus Master software is a driver that is a special driver that must be loaded on the CP441-2, also a dongle for on the backside of the CP441-2 is provided with that software. 3. Siemens sell this driver, it is software that comes with the dongle, you can also already get the software with the earlier download I have given to you. The package I recomended is the COPY LICENS which is some cheaper then the hole package (that you didn't need if you have downloaded the free software package to program the CP's and the software for the Modbus Master where you have to buy the dongle). 4.If you connect everything (is it one Sepam or are it more then one {then you need a multidrop bus)) then nothing is happening, so you have to decide which registers and coils are to be read or write to. 5. There is a Modbus Master thread where I have placed already some software (you are coming on the 2nd page of this thread, see my text from 25.07.2006, 21:40 for some idea how to program it). So you need to know what you want to read/write to this Sepam. Another question from me is, have you aleady this Sepam? When not, there are the same equipment (for instance from Siemens) that are working on Profibus, then you need nothing extra. |
I hope that the answer will help, if you have still questions, don't hesitate to ask me. |
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5/28/2007 8:51 PM | |
Posts: 279 Rating: (30) |
In addition to the previous fine suggestions, you should also consider the the 1SI interface modules to be used in an ET200S distributed i/o station on Profibus. Part number for such a module with Modbus RTU protocol onboard is 6ES7138-4DF11-0AB0. It is significantly less expensive than a CP441 + loadable Modbus driver. As fas as I know the maximum baudrate is 19200, so that may be a limitation for you. Also, if the Sepam system supports Modbus TCP, then maybe this is an interesting option to you as well. There is a library for making an CP443-1 talk Modbus TCP, look here: http://www.industry.siemens.com/IT4Industry/en/solution_services/SIMATIC_Addons/proto_mod.htm |
5/29/2007 8:53 AM | |
Posts: 279 Rating: (30) |
Hi Late. The 1SI module comes in5 variants with the following fixed protocols. 3964(R) ASCII Modbus RTUMaster Modbus RTU Slave USS Master So no JBUS unfortunately. |
5/30/2007 9:29 AM | |
Posts: 324 Rating: (30) |
Hello Dec, thank you for this information... I really appreciate this. Stay calm. |
5/30/2007 5:03 PM | |
Joined: 12/19/2006 Last visit: 2/6/2024 Posts: 5 Rating: (0) |
Hello,
We use ModbusTCP with PCS7 (S7-400 and S7-400H controllers) We purchase a driver block MODBUS from I&S "OPEN MODBUS/TCP no. 2XV9450-1MB00". The block supports Modbus function code 3 (read registers) and 16 (write registers). The block can be used both as client (modbus master) or server (modbus slave). We use the CP 443-1 (both ISO and TCP/IP), have not noticed any conflicts and the data through put is high (compared with the serial CP solution). In case our client only support RTU we could simply add a converter (DIGI ONE 70001777). http://www.industry.siemens.de/IT4Industry/EN/solution_services/SIMATIC_Addons/proto_mod.htm?PIdent=1075&SIdent=1003&TIdent=1016&QIdent=1025 Regards Robert |
8/20/2014 11:54 AM | |
Joined: 9/1/2005 Last visit: 3/5/2024 Posts: 4097 Rating: (193) |
new question published by Ico_76is split to a seperate thread with the subject connect CP441 to Modbus slave RTU devices from Schneider TRV00210 Best regards CS Moderator |
My Forum is the place to personalize your profile, |
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12/2/2016 11:32 PM | |
Joined: 9/27/2006 Last visit: 4/24/2024 Posts: 12257 Rating: (2665) |
Hello Kiiza; See the information in the last part of this FAQ, concerning the ET 200M integrating a CP 341 as Modbus RTU Master (or slave):: Which hardware and software components do you need to establish communication between SIMATIC S7 stations and third-par ty devices using the MODBUS RTU protocol? https://support.industry.siemens.com/cs/ww/en/view/58386780 When you insert a CP 341 in a ET 200M configuration, the configuration of the CP only selects a number of bytes reserved for the exchanges between the Profibus master and the CP 341. This number of bytes (8, 16 or 32 bytes, depending on your communication speed requirements over Profibus-DP) has nothing to do with the number of bytes exchanged between the CP 341 and the Modbus slaves it is communicating with; these are programmed through the Loadable Driver you set up on the CP 341. It is simply to create a channel between the CP and the Profibus master. You then have to program the Modbus functions (made available through the Loadable driver and the dongle to be placed in the backside of the CP 341) in the CPU that acts as a Profibus master. Hope this helps, Daniel Chartier |
Last edited by: dchartier at: 12/2/2016 11:37:05 PM |
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12/6/2016 5:06 AM | |
Joined: 3/28/2010 Last visit: 4/17/2024 Posts: 1029 Rating: (211) |
JBUS, for most practical purposes, can be handled as Modbus. Historically, there was a licensing issue prior to Modbus becoming an open protocol, so JBUS deviated from the Modbus spec slightly. The differences are so minor that in most cases Modbus can be used successfully. The best summary of the differences between JBUS and Modbus are on a Software Toolbox web page: http://support.softwaretoolbox.com/app/answers/detail/a_id/3402/~/jbus-protocol-vs.-modbus-protocol In case the link above goes bad over time, the details from that page are on this graphic image: https://s13.postimg.org/v6uggcgtj/Software_Toolbox_table_for_JBus_vs_Modbus.jpg One must be aware of JBUS' one based register addressing vs Modbus' zero based addressing. But unless the JBUS unit uses the slightly extended addressing scheme, Modbus should be able to address it. |
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