Learning Siemens Step 7

Hi all

Ive now got close to 4 years experience programming PLCs, mainly using Codesys V3 and also Red Lion Crimson software.

The company I work for is considering using Siemens PLCs for some applications.

My question is is there much cross over between Codesys and Siemens Step 7? I use structured text as opposed to ladder logic, i was taught in ST and still haven't got round to/needed to use ladder.

In terms of visualisation, we use Exor HMIs (j mobile is exors proprietary front end software, which has a codesys v3 protocol).

I'm by no means an expert but I'm a fairly fast learner. Has anybody else made the switch from codesys to siemens?

Thanks

ce_ht said:

Hi all


The company I work for is considering using Siemens PLCs for some applications.

Click to expand...

Why are they considering it?

L D[AR2 said:

Why are they considering it?

Click to expand...

I don't think it'd be a permanent thing, some clients have just requested it as it's what they've always used

I am learning different flavors of CodeSys, TwinCat and Machine Expert and have background in Siemens TIA.
IDE is very different and you need to learn that, no way around it. Some concepts are the same but I find CodeSys offers more "advanced" programming, methods, properties, etc.

As mentioned many times, most difficult skill is program design which I am still working on. Coding is just a matter of learning the IDE and available functions and most of all try not to compare, just learn it.

Perspective of a Siemens guy who hasn't used Codesys, but hears about it sometimes:

Siemens uses ST (although they call it SCL) pretty extensively. Most of the code in the app examples on the support site are written in Structured Text.

Siemens doesn't support the extended/updated ST that codesys uses, with methods and all that Object Oriented stuff, it's mostly just the older ST spec. You still get Functions & Function Blocks, if/then, etc. Somewhere buried on the install DVD they have a pdf showing their IEC compatibility, which lists all the ST stuff they do/don't cover. See link below for 2015 version of it, but I doubt much has changed since then.

https://cache.industry.siemens.com/.../att_845621/v1/IEC_61131_compliance_en_US.pdf

I'm pretty sure the tag access syntax is slightly different, when accessing global tags in data blocks, but I doubt that'll be too much of a hassle to figure out, especially since Portal has a decent tag picker.

Be aware that there is STEP7 "Classic" (for S7-300/400) and STEP7 in TIA (for S7-1200/1500).
There are big differences, also regarding ST (SCL). The IEC ST compatibility sheet MK42 linked to is for STEP7 in TIA.

The company with Siemens S7 may be using either or both of Classic or TIA.

Regarding the Exor HMI, then you must also be aware that there are significant differences between STEP7 Classic and TIA.
Some HMI manufacturers claim compatibility with S7-1500, but they always have some limitations, i.e. no support for optimized DBs, and the need for enabling PUT/GET data transfer - which is a security risk.

So in case that the customer is using S7-1500, you should be good if you stick to ST, and you are ok with using non-optimized DBs and PUT/GET is enabled.
https://www.exorint.com/faq/2017/06...in-tia-portal-to-communicate-with-exor-panels

Thank you for the replies everyone, very helpful!

TIA Portal is much more user friendly than the old Step 7 Classic. I try my best to stay away from Step 7 Classic. It can be very unforgiving at times.



My biggest complaint about Siemens is finding documentation and using their website.



However, they have one of the best Tech Support groups of any of the PLC manufacturers.