Interfacing AB Micro830 with Computer using generic RS232 cable

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Hi, I am working on a University project at the moment. The project scope is to implement a simple PID Program for a process tank and implement a SCADA/ HMI using Allen Bradley Micro830 PLC. I know AB has its own HMI/ SCADA hardware. However, the aim of the project is to use software only. So my questions are, 1) is it possible to implement a SCADA/ HMI on the computer with a generic RS232 cable + available SCADA/ HMI software or I need a RS232 cable that specifically made for Micro830? 2) how do I make my Micro830 communicate with the computer via RS232 cable? Are they able to communicate just by having the same modbus code? I am not sure how to do it. 3) how do I go about doing it? What are the available softwares? I thinking of using GE's CIMPLICTY but haven't got around to try it yet.

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You must use Connected Components Workbench from Rockwell to program the AB Micro8XX series PLC's. It is available for free from here -- > http://ab.rockwellautomation.com/Programmable-Controllers/Connected-Components-Workbench-Software I believe you can also program them with the more traditional / standardized AB RSLogix 500, however that is not free software, and will run you around 3 or 4 grand. I would highly advise you to use a full MicroLogix series controller instead, such as the MicroLogix 1100 / 1200 / 1400. The 1100 is about 600 bucks, comparable in cost to the Micro830, but implements a more robust feature set (including communication over Ethernet) in that it actually functions like any other true AB PLC (as opposed to the Micro8XX's, which are somewhat mongrel-ized). That aside... the Micro8XX series can be programmed via a USB cable, however it can only be 'communicated' with (for the purpose of interface / interaction - ie. SCADA / HMI) by using a semi-proprietary AB cable. It is a 9-pin PS2-style Null-Modem. The AB part number is 1761-CBL-PM02 (about 90 bucks from Rockwell) If the PC you intend to use to communicate (interface / HMI) with the Micro830 has a serial port, then you can get this knock-off / no-name version of the cable from a 3rd party supplier for $15. http://www.ind-concepts.com/1761-CBL-PM02a.jpg -- the link to purchase is here http://www.ind-concepts.com/Allen_Bradley_PLC_Cables.htm (scroll down about half way, and there are two on there - one is a right angle style and the other is straight - both work fine). If you do not have a serial port, then you will need one like this... http://www.ind-concepts.com/USB-1761-CBL-PM02.jpg -- which is also for sale on the same page (at the top of the page) for about $30. The drivers for it are Windows XP friendly, not necessarily windows 7 (haven't tried it). As far as shrink-wrap SCADA software... -- AB FactoryTalk View Studio Machine Edition (very pricey) -- OpenSCADA (free open source) - http://openscada.org/downloads/ Be advised that unless you're using an AB product such as FactoryTalk, then you'll likely also need an OPC Server (900 to 2,500 dollars for a license) in order to bridge the communication gap between the two.

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I got this cable (attached) from a friend of mine last week. Do you think its gonna work? I do not have the driver cd tho. As for SCADA, I am really confused at the moment. Must I used a specific SCADA Software to "bridge" my PLC with my PC? Or the cable (attached) is enough? Please enlighten me on this. Can I use software such as redlion / advanced hmi/ labview / citect/ cimplicity? Which one would you recommend? Please let me know thanks. I really appreciate it.

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The cable you got from your friend appears to be a knock-off USB-to-Null-Modem adapter with the correct PS-2 style connector. So yes, that cable should work fine. You will very likely need the windows drivers for the cable though - most USB-to-Serial adapter chipsets (what is inside the 'fat' part of that cable) require a driver of some kind. As far as SCADA software... PLC's typically do not speak "generic" serial comm. Think about it - generic serial comm is nothing more than a TTY, which in the case of a PLC is useless. AB's serial ports almost always use the DF-1 protocol over an RS-232 connection, which is --very-- useful. Some of them use RS-485 with the DH-485 protocol (Data Sidewalk). Other interfaces use 56k (or higher) Token Ring (Data Highway Plus) over telecom, CSP4 over TCP/IP Ethernet, CIP over TCP/IP Ethernet, and god knows how many other things they'll come out with. So... that cable makes your PLC --able-- to talk to your computer, but it does not actually do the "talking". That job is performed by a communications driver. This can be something like AB's free RS-Linx Lite. However RS-Linx Lite can only be the "middle-man" between a PLC and an AB product. For it to allow a PLC to talk to a non-AB product, then you'll wind up having to buy the full version (RS-Linx Classic Gateway OPC Server). Alternatively, you can get a 3rd party OPC Server such as Kepware KEPServer for Allen Bradley, Matrikon OPC Server, InGear OPC Server, etc. etc etc... most will run between 900 and 2,500 dollars. Finally, a few scada solutions out there have built-in drivers, but these are typically software packages that have a 4,000 to 10,000 cost associated with them. If you intend to write your own SCADA back end from scratch, then you'll likely want to go with a standardized protocol like OPC (UA or DA spec), and then we're back to getting an OPC Server.

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Hi, I found the proper software to make my hmi, however, I am having trouble with making my PLC talk to the software via modbus RTU. Do you guys know any other solutions other than paying ridiculous amount of money to buy the opc to modbus servers? Thanks.