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EDWartens UK

Free course · PLC programming

Siemens TIA Portal: Organisation Blocks, Interrupts and Timers

What the S7-1200 and S7-1500 do between your rungs: OB1 and the cycle, OB100 at startup, time-delay, cyclic and hardware interrupts, the error OBs that keep a CPU out of STOP or make a silent fault visible, time of day, and every timer the instruction tree offers.

See the modules

Free to learn. Verifiable certificate £19 when you pass the final exam (optional, VAT included).

Level
Intermediate
Modules
8
Video
7 hours
Price
Free

Outcome

What you will be able to do

Explain the S7-1200/1500 cycle and read its cycle time, use OB100 for startup work, write time-delay, cyclic and hardware interrupt OBs, handle time errors, diagnostic errors and programming errors in OB80, OB82 and OB121, work with system and local time, and use TON, TOF, TP, TONR, legacy timers and clock memory correctly.

  • Read and change the cycle time and use OB1 correctly
  • Do startup work in OB100 such as counting restarts
  • Write OB20 time-delay and OB30 cyclic interrupts
  • React to digital and analog hardware interrupts in OB40
  • Keep a CPU running with OB80, OB82 and OB121
  • Use every timer type, reset and preset them, and use clock memory

Software

TIA Portal V21 trial (21 days) with S7-PLCSIM V21, on 64-bit Windows 11 Pro or Enterprise; any version from V15 on covers what this course teaches

Hardware

None, everything runs in simulation

Syllabus

8 modules

Each module has video lessons, notes and a short quiz. The final exam closes the course.

  1. 1OB1, the Cycle and Cycle Time; OB100 at Startup2 lessons
  2. 2Time-Delay Interrupts (OB20) and Cyclic Interrupts (OB30)2 lessons
  3. 3Hardware Interrupts (OB40): Digital and Analog2 lessons
  4. 4Error OBs: OB80 Time Error, OB82 Diagnostic Error and OB121 Programming Error4 lessons
  5. 5System Time, Local Time and Time-of-Day Interrupts (OB10)3 lessons
  6. 6Timer Types, TON, TOF, TP and TONR, Reset and Preset3 lessonsLab
  7. 7Legacy S7 Timers, Clock Memory and Counting Seconds3 lessonsLab
  8. 8Final Assessment1 lesson

How it works

How this course works

  1. Watch the video lessonsOne module at a time, at your own pace.
  2. Take the module quizA short quiz at the end of each module shows what stuck.
  3. Keep your notesWrite in My notes beside each module and ask the trainer if you are stuck.
  4. Practise in the labOptionalTry a task from the module in the EDWartens Lab, in your browser.
  5. Sit the final examPass it once you have been through the modules.
  6. Certificate, if you want oneOptionalPaid, and only after you pass. Anyone can check it online.

EDWartens Lab

Practise this in the EDWartens Lab

Write and test the same ladder logic in the Lab's PLC simulator, go online and force inputs. The Lab uses a vendor-neutral editor, so brand software stays in the course.

Works alongside Siemens TIA Portal: Organisation Blocks, Interrupts and Timers. The Lab is plc programming practice in your browser: no install, no hardware, free to use. Sign in as a learner and it opens with your account.

Open the free lab See the Lab
PLC programming: Program a PLC, see it run.

Levels to try with this course

Optional. Skip it whenever you like: it never blocks your progress or your certificate.

Why practise in a lab

Technical work is judged on what you can do: wiring, commissioning, finding a fault. Doing a task yourself teaches more than watching it a second time, and a lab lets you try it safely before you meet real equipment. It does not replace working on real hardware.

  • Practise safely, so a mistake costs nothing.
  • The lab checks your work like a site test, so you know when it is right.
  • Free, in your browser, with nothing to install.

Certificate

An optional certificate when you pass

Learning is free. Pass the final exam and you can have a certificate for £19, including VAT, with a number employers can check online. It records that you completed a free online course; it is not a regulated qualification or a CPD certificate.

  • Your name, the course, its study time and your final exam score
  • A unique certificate number and a QR code to its verification page
  • Issued by Wartens Ltd; add it to your LinkedIn profile in one click
  • Pay now or after you pass: it is issued the moment you pass the final

How the certificate works

Sample certificate for Siemens TIA Portal: Organisation Blocks, Interrupts and Timers

Credits

Who made the lessons

The video lessons belong to their creators. EDWartens wrote the study plan, notes, quizzes and the final exam.

  • Hegamurl

    the TIA Portal interrupts and organisation block series

  • Hegamurl

    the TIA Portal timer series

Questions

About this course

Is this only for the S7-1500?
Most OBs and all the IEC timers work the same on both. The legacy S7 timers run only on the S7-1500, and a few error OB reactions differ; the notes say where. Everything is shown in PLCSIM.
Why do I need error OBs?
Without OB80 or OB121 a cycle-time overrun or a programming error can put the CPU into STOP, and the line stops with it. Without OB82 a module fault such as a wire break goes unreported. With them the fault is logged, an alarm can be raised, and the CPU keeps running.
Is the course really free?
Yes. Every module, practice task and assessment. You create an account so your progress is saved and the assessments can be marked. The certificate is the only paid item, and only if you want it.
What certificate do I get, and is it a Siemens qualification?
An EDWartens Certificate of Completion, issued when you pass the final assessment, with a verification code anyone can check. It is not a Siemens credential and is never described as one.
Who made the video lessons?
The creators named in the Credits block at the foot of this page, on their own YouTube channels. EDWartens did not make the videos and the creators are not affiliated with EDWartens. What EDWartens wrote is the study plan, the notes, the practice tasks and the assessments.
How long does the course take?
Plan on about 6 hours in all, including the video lessons, notes and practice tasks. It is self-paced, so you work through the eight modules at your own speed.
Do I need a real PLC?
No. Everything runs in TIA Portal with S7-PLCSIM, which you can use on Siemens' 21-day trial.

Siemens engineer path

Take it with

See the whole path

The Professional Module is five live days of Siemens PLC, HMI and SCADA with an instructor, then a resume session and a CPD certificate.

See the Professional Module