Siemens S7-300

I have been programming PLC's for a number of years and have used AB, Omron, Mitsubishi and Siemens S7-200.

I am now looking at a project that requires a S7-300 to be used, never having used one before are there any good/bad pointers anyone can give for the S7-300.

Any advice would be appreciated.

Nick,

when I see your biography I think you better start from the beginning if you want to tackle S7-300. It has no affinities whatsoever with the PLC's you already know.

I think taking a course would be a good start (the only possible start if you ask me!).

Kind regards,

Correction!

Since you can program S7-300 with ladder, it has at least one thing in common with other PLC's.

Kind regards,

I'll drink to something

I am a 20 year PLC guy, and almost started selling life insurance
when I started a Siemens project.

The thing I tell everybody is that Siemens is all about the
'data', while AB (et al) are all about the 'I/O'.

Yea, 'can' everything you think you will be able to re-use from
your AB days...

And, don't hesitate to use the support 1-800 number. Those guys
are good at answering good questions... but, in the beginning, you
won't know how to ask the right questions.

Also, if, while you're researching, it looks like the 'code' guys
didn't talk to the 'hardware' guys.... well, I don't think they
did.

THAT was the hardest thing for me...connecting the hardware to the
software/code.

I have been working with the S7-300 (Step 7) for a couple of years now after programming AB for 10 years. The switch was very tough at first, but now it is easy to work with. They offer so many paths it was hard to even figure out where to start (byte based and upper byte transposed are all confusing). I used ladder for anything that a field service or maintenance person would need to look at. For things that I could define I used SCL or ladder code to create a protected function or function block (like an encoder position calculation) depending on the needs. Think code re-use. Create generic functions and function blocks. Lean heavy on the technical support and get as much help from the local apps engineer to get started.

I was a GE Series 90 guy. When I made the switch to SIMATIC, you can believe that I had many sleepless nights. Take my advice and take class or find a guru and leech him to death.

With Simatic is helpful if understand how the processor works with its accues. That documentation missing defaultly and I don't even know is it available, I have it from S5-series and it is equal, I think.
Step 7 developper is confused and not help how to start, but with hard work and this forum it is possible to do without extra training.
As jdbrandt told, you must know the person in Simatic support and his/her direct tel.number who knows what you like to know -at last in here-.

I delegated our first Siemens project (an S7-315) to one of the other guys here, my ace engineer Tim. He did as much as possible in ladder logic, mostly because we have so much control on other platforms in ladder logic already. I did try to stay close to Tim on the project, though, mainly because if he had succeeded in slitting his wrists I'd have had to do the programming myself. We now have a new "least favorite" platform.

Siemens documentation is voluminous, obscure, and not well cross referenced. Their data handling is obscure, poorly documented, and has many conversions that are unidirectional. The memory map and nomenclature are arcane arbitrary, and difficult to access from the MPI communications link. I was amazed at how few timers were available - we nearly ran out.

The phone number for tech support is so well hidden it took days to get it. Our local distributor was AWOL - getting training of all things. Tim finally got ahold of a tech support guy in Germany, who identified a number of undocumented capabilities that made completing the job possible. If we had had the time to get training I would have invested in it, but deadlines and customer demands precluded it.

My overall impression is that Siemens makes good hardware, but they are more adept at discrete logic than analog control. They seem to think that their customers should really just pay them to do the prgramming, and not try to do it themselves. If something is obscure or difficult to implement, that's OK - your time is your money, and if they have to help out or sell you more tech support programs, that's just more revenue for them.

After some of the raves about Siemens from guys on this forum, I was incredibly disappointed. We'll use Siemens again, but only if the customer makes us.

If time is available, get any training available and pay the extortion for the tech support upgrade.

Nick,
It sounds as if I am the opposite to you in that I started my PLC life 3 years or so ago with Siemens S7 and I am now getting into AB.
I think my learning curve with S7 was ideal since we were supplied a new plant from a process supplier and their software guy was very good and by studying the code supplied by them as well as much reading and "playing", I was able to get a good introduction to S7. As well as many queries back to supplier, local Siemens S7 training course plus consulting a few local "experts" plus enrolling in a local college PLC course.
Since it was my first detailed PLC experience and I knew nothing else- I thought the S7 system was brilliant and very impressive- hopefully, from comments posted above, I will now find AB to be very user friendly.
Good luck, ColinA

Colin brings up a good point. Even though he stole my avitar!... (Only kidding!... )

I think it has a lot to do with your introduction to PLCs. IOW, your first experience has an influence on your definition of what's 'easy'.

I taught myself programming 'way back when' with the Omron C-series PLCs, but while I was still quite 'green', I got a slew of high speed production lines dumped on me with Siemens S5 processors. It was completely different than Omron, but I was not 'set in my ways' yet, so I was more open to learning it. A big help was that I wasn't starting out from scratch. I already had well-written, fully-documented programs to study. To put it plainly, I would NOT want to have had to learn Siemens on my own!

beerchug

-Eric

I wish you well. My first Siemens project was a rush job of course. No time for training, if you could afford it. Generally people love or hate Siemens. I belong to the latter group.
Software dongle disk crashed - had to get another one from Singapore - took 1 week. Unable to use the software in this time as the temporary dongles were on the same floppy disk.
The processor would "see" the expansion arck and could not see it. Flew from Brisbane to Sydney several times to Siemens support group. The first time they wer in training and no one was available. That went down well.
They got the processor talking to the expansion rack after 5 hours with 2 people on the job. You would think that would let them know there was a problem. You have to be kidding. Went back to Brisbane and the expansion rack was invisible again.
The Brisbane rep finally arrived with a high end processor and all was well. Turned out to be an "undocumented feature" of the processor we used. Cost me 11/2 weeks of time and threats of liquidated damages, not to mention 4 lots of air fares at full economy rates and 11/2 weeks of accomodation and taxis.
Siemens wonder why I tell them to go away and use their PLCs as anchors.
Then there was the issue of software. Offline and online screens. Wonderful. To do an online programme change, go to the offline screen. By the time you get back to the online screen it has all happened. You cannot see the effect of your changes. Hope they have fixed the software.
The other lovely feature was that the software downloaded the whole programme instead of opening it up and inserting the cahnges. You could hear relays changing - going off and then on again as the scan caught up - end of online programming.
We were hooked into anothe SIs Profibus DP network to send and receive data. Watch out where you put the send and receive commands in the programme or it will not work.
Good luck.
mddr beerchug beerchug beerchug

BobB- wow, what an introduction to new technology- hopefully you've now finished the stress therapy sessions.
Eric, sorry about your Avitar- I sort of thought it looked a bit like a kangaroo, hence the choice.
ColinA

Why not Siemens Step7-200

Dear Sir,
Just a little experience from my small brain.
If you are familiar with AB...or Modicon...or Ladder Style..
I recommmend you use Siemens Step7-200 (former ..Texas Instrument)
Easy to use as you familiar with.

Best Regards,
A.Char

Thanks for all the replies, it looks like getting another person to write the software and sitting on their shoulder is a good way forward.

Doing a Siemens training course is the best option but it depends if the price of the course and loss of earnings whilst on the course can be justified for the amount of Siemens work I can pick up.


Thanks for all the avdice.

Tom Jenkins said:

After some of the raves about Siemens from guys on this forum, I was incredibly disappointed. We'll use Siemens again, but only if the customer makes us.

Click to expand...

Tom, same here. I have done 80% of my PLC programs by Simatic since 1978. In spite of that, I don't like Simatic.

Today, we like to change old S5-95U PLC's I/O to remote-rack for some S7-300-PLC for process extension. Siemens don't like sail IM318-card to us, becourse it is their old-model I/O and they like to sail us new model (S7-300) remote I/O for replace our S5-100 series I/O.
I think that is unnecessary expensive for the customer, maybe we have to replace whole Simatic by some other manufacturer PLC, it depends of costs.