🔍 Key Concepts

• Triac thyristor structure: essentially two SCRs connected in opposite directions with a single gate • Difference between SCR (silicon controlled rectifier), DIAC, and TRIAC symbols • Terminal labeling: TRIAC main terminals are usually MT₁, MT₂, and G (gate)

💭 Think About

• Look at which symbol shows current control in both directions between the two main terminals, rather than in just one direction like an SCR • Compare the number and names of terminals: which one has MT₁, MT₂, and G instead of A/K or E/B? • Check which symbol has two opposed thyristor/diode shapes inside, sharing one gate connection

✅ Before You Answer

• Confirm the symbol you pick has three terminals (two main terminals plus one gate) • Verify the two main terminals are marked something like MT₁ and MT₂, not A/K or B/E • Make sure the internal symbol looks like two back‑to‑back SCRs (two arrows/diode shapes pointing in opposite directions), indicating bidirectional control