Changing from Allen Bradley to Siemens

[mart 0]

Hi, Currently I'm using Allen Bradley RSlogix 500 for fault finding and trouble shooting but not as a PLC programmer, Due to a job change I'm required to have a knowledge of Siemens PLC's. I believe Siemens do not display like ladder logic so it maybe something I've not come across. I would appreciate it if anyone could give me their ideas in the difference of the two programs along with any links to simulation programs for siemens PLC's. All help would gratefully recieved. regards Mart

[Crossbow 296]

Which Siemens PLC? You don't mention a family (S7-200, S7-300, S7-400, S5)... Siemens current products (S7-xxx) programs in the 5 IEC languages. So the code could be written in ladder logic, as that's one of the languages. The others are flowchart (SFC), instruction list (like C programming), function block (like ladder but no power rails and more freeform), and statement list (like old handheld programmer mnemonics from days gone by). Siemens has a CD called Step 7 Step By Step which you should be able to get from a Siemens distributor, which is a walkthrough to introduce the Step 7 programming software and IEC programming. It might help you out. The S7-200 PLCs program with a smaller package called Step 7 Micro/Win32. This allows for ladder and function block programming. The S5 I don't know much about as it was before I became involved in Siemens products.

[mart 0]

Thanks Chris, At present I don't know which particular Siemens program I will be using but I'll get in touch a distributor and have a good look through the disc. Thanks for your help Mart

[lambles 0]

S5 only as STL (statement list), Ladder & CSF with STL being the dominant language. Anything more tricky than contacts & output coils cannot be displayed in anything other than STL....eg as soon as you put a timer in a rung, no more ladder. And if you start using function blocks (very common in S5) you don't get to see CSF either. So if it's S5 you might need to learn STL.