Siemens Statement Lists

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Thread Starter

Nathan CHAFFEY

Can anyone please tell me where I can find information on Siemens Statement Lists (STL). I am working on a project which requires me to
understand this type of logic. The majority of my past PLC experience has been in dealing with AB ladder logic.

Any help would be greatly appreciated,

Regards,

Nathan.

Nathan. J. Chaffey
Technical Systems Engineer
Anchor Products Limited
Engineering Services

phone (07) 850-7534
fax (07) 849-7855
 
A

Amr Elaguizy

Nathan,
STL is very similar to machine language, without ordering the Siemens instruction book for a particular CPU it will be difficult. Since not only you have to understand the STL, you will have to understand the various functions and objects blocks, which is confusing for a programmer of AB PLC to a Siemens PLC. I went through the same thing few years back and it drove
me nuts.
Regards,
Amr Elaguizy
[email protected]
 
P
STL is basically the "text version of ladder"; all
conditions/actions/functions and logical operations that you insert/connect graphically in ladder must be written in ordered sequence
in STL. If you are using STEP 7, however, you can program everything in ladder (not so in STEP5) and view your program blocks in ladder, STL or
FBD (function block diagram). You can download Siemens manuals from:
http://www.ad.siemens.de/simatic-cs -> product support -> software. For specific help you can contact me directly by e-mail.

Regards,
Peter Kosin
Process Control Engineer
INEA d.o.o.
[email protected]
 
M

Michael Griffin

At 10:29 05/01/00 -0500, Nathan CHAFFEY wrote:
<clip>
>Can anyone please tell me where I can find information on Siemens Statement Lists (STL). I am working on a project which requires me to
>understand this type of logic. The majority of my past PLC experience has been in dealing with AB ladder logic.<
<clip>
I assume you are referring to S5 STL? The S5 family is different from the S7-200, which in turn is different from the S7-300/400. I am assuming S5 because if you meant one of the two S7 families then you probably would have used the IEC term of "IL", rather than "STL". There are two sources of information. One is the processor manual, where each instruction is individually explained. The other is in a book published by Siemens called "Automating with the SIMATIC S5-115U" by Berger. This book is commonly referred to as the "Berger book". It is written specifically for the S5-115U, but most of the S5 STL instructions are common to the whole S5 family. Some of the technical detail in the Berger book is better explained than in the processor manual, but unless you intend to become an S5 expert, it is probably not worth buying.

You should read up carefully on how S5 timers and counters work, as these are very different from AB (which is what you are used to). Also make sure you study how the various blocks work. Note that certain instructions are allowed to be used only in FBs, but not in OBs, PBs, or SBs. Also note word versus byte addressing in Flag Words, and that Data Words are different again.
The programming software (there are several third party packages available besides Siemens STEP-5) should allow you to switch between STL and ladder. All segments written in ladder will translate to STL, but not all STL segments will translate to ladder. One reason for this is that one large segment of STL can actually be equivalent to several smaller segments of ladder. People tended to write large, complicated STL segments rather than several smaller rungs of ladder because of certain shortcomings in the Siemens STEP-5 program editor.
Once you have an instruction reference, the best way to learn STL is to write a rung in ladder and then get the software to translate it to STL, and visa-versa. If you don't understand an existing large complicated segment of STL, then copy smaller parts of it to a new rung and see if you can translate them to ladder.
If you are writing new logic, then write as much of it as possible in ladder. The actual instructions the PLC uses are the same, the difference is how they are displayed on your computer screen. A segment (rung) of ladder results when the programming software recognises a certain pattern of instruction codes. If the programming software cannot fit the segment into
any of its defined patterns, then it has to default to displaying it as STL.
Certain features (instructions) are only available in STL format, but all the normal contacts, output coils, timers, etc. can be written in ladder. STL format can be very usefull for certain purposes. I wouldn't use it though where ladder representation will serve.
Some people prefer to write their programs entirely in STL. The only explanation I can think of for this is that they seem to believe that if they do something which is difficult, then they must be clever. I don't
necessarily agree with this reasoning.

**********************
Michael Griffin
London, Ont. Canada
[email protected]
**********************
 
D

D.C. Pittendrigh

Hi All

Siemens sells a very good book by a guy called Hans Berger in which the mechanisms of STL are explained. Remember that there is very little reason to program in STL if you don't like it, the latest version of the S5 programming
package, allows damn near anything to be converted freely into IEC1131 type graphics. It is not considered to be friendly to program complex arithmetic functions etc in this way, but if you have no option, what the heck.

I must also defend the Siemens product, it is not really that difficult to handle STL, it does however require a different mindset as the power and flexibility is incredible compared to most other products. Literally nothing is "done
for you" even relatively simple functions must be self generated, but wait till you get into a difficult situation where you need something special, Siemens PLC's no problem, many other PLC's, no possibility.

Cheers
Donald Pittendrigh

> Nathan,
> STL is very similar to machine language, without ordering the Siemens instruction book for a particular CPU it will be difficult. Since not only you have to understand the STL, you will have to understand the various functions and objects blocks, which is confusing for a programmer of AB PLC to a Siemens PLC. I went through the same thing few years back and it
drove me nuts.<
 
Hello,

Peter Kosin:
> STL is basically the "text version of ladder"; all conditions/actions/functions and logical operations that you insert/connect graphically in ladder must be written in ordered sequence in STL.<

If that's so, I can maybe provide another point of view; I never really understood the (Mitsubishi) text stepladder until I read an ex-eastern-bloc manual (Tesla).

The Tesla manual explained it as a stack language.

In that explanation, LD is the push instruction, AND ands the input with the top of stack etc, but OUT simply copies the top of stack to the output.
The stack is hardly ever popped - excess entries just drop off the bottom - though the AND-BLOCK and OR-BLOCK combine the topmost two entries into one.


You may find this more or less confusing depending on your background.

Jiri
P.S.: I think Tesla is actually a bunch of baby Teslas, but I don't
remember which one it was.
--
Jiri Baum <[email protected]>
On the Internet, nobody knows if you are a @{[@{[open(0),<0>]}-1]}-line
perl script...
 
Another resource,
Programmable Logic Controllers by:
S. Brian Morriss
Pub: Prentice Hall
ISBN - 0-13-095565-5

You may try the Siemens Library
http://search.siemens.com/cgi-
bin/query?mss=en%2Fsimple&pg=q&what=web&enc=
iso88591&fmt=.&backtolink=http%3A%2F%2Fwww.siemens.com%
2F&backtotext=Sieme
ns+AG&filterurl=&filtername=&cfilter=&smartweb=&password=&filte
r=all&kl=XX
&q=library%2Cstl&FormHandler1=Submit
 
L

List Management Account

---------- Forwarded message ----------
From: Wim Vrinds <[email protected]>
To: "'The Automation mailing list, managed by Control Technology Corporation'" <[email protected]>
Subject: RE: LANG, INFO: Siemens Statement Lists

Hello all,
more information on Siemens PLC's can be found on their web-site.
Have a look at www.ad.siemens.de and goto product support.
www4.ad.siemens.de/infocs/livelink.exe

With kind regards, Mit freundlichem Gru=DF,
Met vriendelijke groeten, Bonne Salutions,=20

Wim Vrinds,
Software & commissioning engineer,
System Controls Division,=20
Stork BP&L B.V.

From: "Nathan Chaffey" <[email protected]>
To: <[email protected]>
Subject: LANG, INFO: Siemens Statement Lists

Can anyone please tell me where I can find information on Siemens
Statement Lists (STL). I am working on a project which requires me to
understand this type of logic. The majority of my past PLC experience
has been in dealing with AB ladder logic.
Any help would be greatly appreciated,

Regards,
Nathan.
Nathan. J. Chaffey
 
M

Michael Griffin

At 14:35 12/01/00 -0500, Tanweer Ahmed wrote:
<clip>

>Also note that Load and Transfer functions no matter how small your logic is
>are not translatable to ladder or CSF.
<clip>
Not necessarily. Visual representation of the program is a feature
of the programming software, not the PLC itself. There is at least one third
party programming package that represents a "load/transfer" pair as a ladder
box "Move" instruction. Siemens actually used to sell this package under
their own name here as an alternative to Step-5, as at the time they felt
that the user hostile features of Step-5 were hurting their hardware sales.
The ladder representation format which this package uses is quite different
from the one Step-5 uses.

On a slightly different note, I notice that there is a Dutch company
(ATS I think?) which is selling Siemens compatable programming software in a
modular system. I think they offer a base package which allows you to
program S5 PLCs in statement list. Ladder and Grafcet are add-on options.
*S7* PLC software is an additional add-on. They also appear to sell clones
of some S5 hardware.
Does anyone know anything about these products? Are they any good?
Are they used very widely?

Michael Griffin
London, Ont. Canada
[email protected]
 
D

D. Pittendrigh

Hi All

> <clip>
>
> >Also note that Load and Transfer functions no matter how small your logic is are not translatable to ladder or CSF. <clip> < <
> Not necessarily. Visual representation of the program is a feature of the programming software, not the PLC itself. There is at least one third party programming package that represents a "load/transfer" pair as a ladder
box "Move" instruction. Siemens actually used to sell this package under their own name here as an alternative to Step-5, as at the time they felt
> that the user hostile features of Step-5 were hurting their hardware sales. The ladder representation format which this package uses is quite different from the one Step-5 uses. <
<clip><clip>

Not a problem with the latest version of S5 software, load and transfer will show up in LAD and CSF, in fact I think it was already possible from Version 6.

There was a company called Greysoft that manufactured a Simatic programming package that was marketed by Siemens, it worked, that's about all that could be said about it in my opinion.

There are currently several packages for programming Simatic which are non-Siemens, in my opinion the only worthwhile one is called S5/S7 for Windows, if anyone is interested I will find the supplier details, however a simple web
search will probably also find it, they are a German company.

> On a slightly different note, I notice that there is a Dutch company (ATS I think?) which is selling Siemens compatable programming software in a modular system. I think they offer a base package which allows you to program S5 PLCs in statement list. ...<
<clippity, clippity clip>

Dutch company, I do not know of, but would be interested to hear more if someone else does, Simatic is my no. one religion and I like to be up to date.

Cheers
Donald
[email protected]
 
M
Very good, though of course not perfect. The ladder representation is about the same as Step 5. Project management features are fairly basic, but as all data is entered in standard Windows text you can cut and paste code and assignment lists from text editors and spreadsheets for example. One excellent feature, is the ability to view an entire function block in text. Program blocks can easily be exported to text files (one per POU), which allows for the creation of libraries and template applications (although management has to be carried out externally). There is also a built in PLC emulator so you can test your code (well, a good portion of it) without a PLC. The software acts as a DDE server, both to the simulation PLC (so SCADA can be tested as well) and to the physical PLC. There is or was a limited evaluation version (limited to four blocks, no printing, no connection to real PLC (but with the simulation and DDE)). This in its own right is invaluable as a training/testing aid. I don't know if the evaluation is still available (try ), if you cannot get hold of it, I have it and may be able to e-mail it or upload it for download (its about 5MB). Regards Mark Hutton Software Engineer Vogal Software Services Regent House, Welbeck Way, Peterborough. UK PE2 7WH Tel: +44 (0)1733 370789 Fax: +44 (0)733 370701 [email protected]
 
M

Michael Griffin

At 00:03 14/01/00 +0200, D. Pittendrigh wrote:
<clip>
>There was a company called Greysoft that manufactured a Simatic programming
>package that was marketed by Siemens, it worked, that's about all that could
>be said about it in my opinion.

This is now sold by Fastrak as both DOS and Windows packages. There seemed to be two sorts of opinions about Siemens Step-5. The people who used it all the time liked certain features about it. Most of the people (at least the ones I have spoken to) who only needed to use it occasionally seemed to hate it. I think the Greysoft package was intended for the latter
market.
The Greysoft PLC software product line got taken over by:
FasTrak SoftWorks, Inc.
http://www.fast-soft.com/


>There are currently several packages for programming Simatic which are non-
>Siemens, in my opinion the only worthwhile one is called S5/S7 for Windows,
<clip>
I believe you are referring to IBH Softec
http://www.ibhsoftec.de
I wrote:
>> On a slightly different note, I notice that there is a Dutch
>>company (ATS I think?) which is selling Siemens compatable programming
<clip>
D. Pittendrigh replied:
>Dutch company, I do not know of, but would be interested to hear more if
>someone else does, Simatic is my no. one religion and I like to be up to date.
<clip>
ATS Applied Tech Systems BV: Industrial Automation
http://www.ats.nl

What I can't tell is if ATS is simply selling a relabelled version of IBH's software. They also by the way sell S5 CPU, EPROM, and I/O clones, and S7-300 I/O clones.
There was also a company (English I think) which had S5 compatable software. It was sold here for a while by Taylor.


Mark Hutton wrote:

>Very good, though of course not perfect.
>The ladder representation is about the same as Step 5.
<clip>
Were you referring to the ATS or IBH? Or do you know if in fact these two are actually the same thing?

**********************
Michael Griffin
London, Ont. Canada
[email protected]
**********************
 
ATS hardware:
Some of our customers use their S5-clone product. They are really pleased with them, because they often offer more for a lower price. The only reason our compagny prefers the original Siemens products, is because of the support and warranty on the Siemens products in the same PLC rack. With Siemens we sometimes get the feeling they are very good in finding excuses why they are not to blame is something doesn't work (what about using a backup battery of another make than Siemens.......).

ATS S5 programming enviroment:
In some ways better then original Siemens enviroment.(Windows support & windows printer drivers, build in simulator, better copy paste, etc.) But you can't use the optional Siemens packages for Communications Processors etc. from the software.

ATS S7 programming enviroment:
We had a trial version about 2 years ago. It only supported the S5 instruction set to be used in S7.
This version was much cheaper than the Siemens version, and you really got what you pay for....
Not a lot..... I hope for ATS this has been improved in those 2 years. We are pretty happy with the original Siemens enviroment for S7.


With kind regards, Mit freundlichem Gru=DF,
Met vriendelijke groeten, Bonne Salutions,

Wim Vrinds,
Software & commissioning engineer,
System Controls Division,
Stork
 
E
Hi All:

I have been informed that SIEMENS does not supply that book anymore. Any idea where we can get a copy will be highly appreciated.

Regards,

Ehab Rofaiel
Ontor Limited
Toronto, Canada(416) 781.5286
[email protected]
 
If you want to learn simatic S5 or S7 you should
download two software (demo) at
www.mhj-software.de

these software allowed me to program perfectly
so, I shoud this it will be the same for you...

Bye.
Bosmans Emmanuel
automation and process control
FAFER BELGIUM
 
Goodluck, the best way of deciphering statement list is to write logic in ladder logic and then convert it to STL in the programmer. Siemens manuals are woeful. Graham
 
Nathan all you have to do is ask....I have many years experience with STL...I am one of those sad individuals that prefers it to ladder....
Terry McG
 
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