home plc

[sopic]

Hi everyone! I'm new in plc programing and I need some help, please. I want to build up my on plc at my home(educational goals, for me) and I was very gladful to find on ebay plc Allan Bradley less than 200$, with the specification "Complet system". I ask the seller if it's all I need. Except, of course, software and cables which is normaly my duty to find them. But they told me I need this and that... I know that for using a plc I need the processor modul, the input/outpus modules, power supplay, counter, comunication module(for linking with PC). I have at my home jyst a PC. What do I need(except cables and software, again) to connect the plc, to install the software and run aplications... etc. ? Could somebody give me a complete list of all modules which will permit me to torn off/on a lamp, to close a switch... or something like that with a plc. I'm afraid to buy and to find out that I just have separate modules without use them. I thought at All Bradley SLC 500 because I saw that are the most on ebay at a resonable price. Thank you all of you!

 

[mikek10]

I would look for siemens s7 200 series or possibly even logo depending on your experience and number of IO.

Both have all the features you need as standard. Logo you can even enter simple programs through onboard keypad, very different to a standard PLC but for occasional users can be ideal.

 

[mikek10]

Here is a Logo

http://cgi.ebay.co.uk/SIEMENS-LOGO-...222359398QQcmdZViewItem?hash=item290222359398

and S7 200

http://cgi.ebay.co.uk/SIEMENS-S7-20...222358028QQcmdZViewItem?hash=item290222358028

 

[ScottyUK]

The 1747-UIC is a useful way to connect to the SLC-500 processors with a DH-485 port. Those with a serial port just need a serial cable. Depends which processor you bought. A-B's RS Logix software is relatively pricey.

Can you list all the components you have in the PLC you bought? Maybe then we can suggest what you are short of.


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If we learn from our mistakes I'm getting a great education!

 

[jraef]

I think you may be underestimating the "software" part of that. It is NOT free and can be difficult to attain on old used systems.

If you are in North America somewhere, look for a good Siemens Technology Center (a type of distributor focussed on automation) and find out if they have an S7-200 introduction seminar coming up. They will sell you a training unit PLC, software and demo input switches for about US$200, along with a 1/2 day introductory programming training session. Makes for a great home PLC to play around with when you are done, a lot of people even use on Christmas lights, use them as sprinkler timers or to make their houses look occupied.

 

[controlsdude]

s7-200? why don't you tell him just go buy a TI PLC or a modicon, same thing. Lets just time travel back to the 80's, thats what your getting. But for that price its a start.

 

[NWBeaver]

Siemens does offer a free lite version of the STEP7 programming software, which can be downloaded from one of their websites. It has limited capabilities, but works okay for a simple system.

 

[mikek10]

S7-200 is more than capable for any "home" application IMHO. What advanced features do you think the OP requires that justifies spending extra cash?


Also s7-200 is a damn site better than any modicon (again my personal opinion), some people love Modicon, I just don't see why.

 

[mvaske]

It depends on what SLC 500 processor you purchased.
The communication options are as follows.

SLC 5/01 and 5/02 - DH485 comms only, which requires an expensive PIC module or PCMK card and cable.

SLC 5/03 - DH485 and RS232 comms. With RS232 you can use a null-modem serial cable and the serial com port on your computer.

SLC 5/04 - DH+ and RS232 comms.

SLC 5/05 - Ethernet and RS232 comms. You can communicate over ethernet, but you will need to set the IP address serially using RS232.

For all of these you will need RSLogix 500 and RSLinx software. RSLinx is used to establish communication from the PC to the PLC. RSLogix is the ladder logic software. AB has a "Starter" edition of RSLogix 500, but it lists for $560. It comes with RSLinx Lite.

I would recommend trying to re-sell your SLC 500 and buy a an Allen Bradley Pico controller, a Siemens LOGO PLC, or a TECO PLC. These are basically programmable relays that use ladder logic. They have inputs and output, some even have analog capability. You can pick one up for a few hundred dollars, but best of all, the software is free. There are limits to what you can do with these PLCs, but they are great for learning ladder logic.

 

[skills]

I don't know if you still require a plc or not; but, you could buy a DL-05 DirectLogic for about $109 and the programming software DirectSoft5 is available as a free demo providing your program is shorter than maybe 100 lines.

Forgiveness is giving up hope for a better past.

 

[ozmosis]

Maybe you should be looking at "Home Automation" rather than industrial automation. This is the growing trend (for the lazy buggers who can't be bothered to get off their arse to switch a light on/off..) and avalable from a few big companies:
Siemens

http://www.automation.siemens.co.uk/main/business groups/et/smart homes/

Niko

http://www.niko.eu/Homepage/fs_index.asp?country=4&lang=EN

or for the bus systems that pull it all together then an interesting one is KNX

http://www.knx.org

 

[jonesy29847]

I would also recommend Automation Direct, their programming soiftware may still be free, it supports all AD processor families. I would get an input simulator, an input module rated at the voltage you are using and a contact output module.

 

[Watthour]

Just avoid anything which uses any kind of "flowchart" programming. Stick with something capable of supporting either ladder programming or some form of BASIC/C programming logical text. It's all Boolean logic, but the graphical flowchart systems are really designed to allow accountants and non-technical people rather than engineers and maintenance people to compile binaries.

2¢

 

[roydm]

I recently did a couple of projects with Opto22, their programming is "flowchart". It certainly is a challenge after ladder. Opto run their whole factory using it, high speed board stuffing etc.
I think it would be OK for home automation as it's really cheap and the software PLC & HMI is free with no licence files that restrict you to one PC. However I agree with Watthour if you want to learn PLC programming something with Ladder, Function Block and Structured text would be better.
Roy