How to study here

  1. Definition: what it is and where it's used
  2. Look and symbol: the real device and its IEC and NEMA symbols
  3. Try it: press, turn and move it, and watch the contacts
  4. Wire it: terminal → terminal, then switch on the power
  5. Questions: quick ones to make sure you've understood

The fundamentals start here, in order

Practical exercises (24) each exercise is a power circuit + a control circuit · exercises 1–4 in the contactor lesson, 5–13 in lesson 8, 14–24 in the timers lesson · and lesson 9 adds 13 more exercises on the advanced topics

Advanced topics

Course Completion Certificate

Symbols according to IEC 60617 and NEMA ICS 19, and terminal numbers according to IEC 60947-5-1. Your progress is saved on this device only. Check the numbering of the device in your hand against the manufacturer's catalogue.
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