programming standards 1

[IngoFederle]

I have been programming PLC's for many years.
Lately our customers requested a written standard for program development.
Does anyone have a generic document I could start out with.
Or is there any place I can get more information about
programming standards.
Our main controllers are AB SLC , Omron c-series.

Ingo Federle

 

[ctolbert]

Hi:

The only standard that I know of is IEC 61131-3. Some companies use this as a standard, but mostly in Europe.

It has 5 languages:

1. Ladder diagram
2. Function block diagrams
3. Sequential function charts
4. Instruction list
5. Structured text.

You can find a lot more information at KW software

http://www.age-usa.com.

Most of the European based plc companies have this as an option.

In North America, I haven't seen any standards at all. The language is mostly ladder although their are a few insurgents with flow-charting.

The biggest issue with ladder logic is non-standardization from mfg to mfg. The basic logic functions are very similar, it doesn't start diverging until you get to higher logic functions.

I hope this helps some.

Carl

 

[rockcontrolman]

IngoFederle:
I did a search and found a website with a document written for the U. S. Department of Energy Multilaboratory Project "Spallation Neutron Sources". It is fairly new, written 12/21/2000, and uses up-to-date plc's, A-B ControlLogix and SLC-500 family. The language is somewhat dense, and it is specific to this project and the software used for data collection, but I think it may serve as a starting point or framework for your own document.
The website is:

http://www.sns.gov/projectinfo/ics/119/ctrlStdsHandbook/ctrlStdsTOC.htm#sw

Good Luck!

 

[ltech]

THERE IS AN ICE STANDARD THAT IS USE IN THE US IF FACT YOU SHOULD NOT PURCHES SOFTWARE THAT DOSE NOT COMPLY IM AT HOME AND DO NOT HAVE THE NUMBER IT DETERMANS HOW YOUR SOFTWARE PROGRAMS AND ALL SOFTWARE AND COVERS MOST ALL PLCS AND PART OF THE STD. IS LADDER NOT LIST STATEMENTS. ALL GM PLANTS REQUIRE IT
TED

 

[HCBFlash]

ltech and ctolbert, I haven't discovered any good links. could you specify? KW Software's sight is in Deutsch. The ICE std sounds familiar, but I'm not up to speed on that stuff currently.

I hope I'm not seen as taking over the thread. I'm still new around here.

 

[WAGOIOSYSTEM]

I noticed some people have responded to you with the IEC 61131-3 programming standard but have not given you the correct link for more information. The association responsible for this standard is PLC-OPEN and can be found at

http://www.plcopen.org.

The company I work for WAGO offers a fully compliant IEC 61131 software tool ($600.00 site license for all 6 languages) - check us out at

http://www.wago.com.

This is truly becomming the programming standard worldwide not just in Europe. In fact, major PLC vendors such as Rockwell - Allen Bradly are now supporting this as their programming standard as well (be careful though - they charge for language add-ons).

 

[GerH]

Indicative contents of our PLC software development
standard are:

1. Steps to establish user requirements.
(Obligations to keep the customer off your back).

2. Items to define the structure of the programme.
Normal sequence of operation,
Safety/shutdown functions,
Special features ( e.g. startup from cold ),
Alarms,
Operator interface,

3. Items to define coding rules:
Symbol / tag naming,
Memory allocation,
Block/segmnent naming/numbering

4. Items to define testing.
Testing in the factory ( at coding)
Testing on site
Performance tests ( real operation)