220V to 9VAC 300mA EI Step-Down Transformer (Single Secondary)

Overview 🔌 Compact EI transformer converting 220–240 VAC to 9 VAC @ 300 mA (≈2.7 VA). Single secondary (NOT 9‑0‑9) . Great for small sensor/logic rails via rectifier + regulator. Key Features ⭐ Primary: 220–240 VAC, 50/60 Hz Secondary: 9 VAC (RMS), 0.3 A Approx. power: 2.7 VA Open-frame EI core Detailed Specifications 📐 Parameter Value Notes Input 220–240 VAC 50/60 Hz Output 9 VAC @ 0.3 A Single secondary Power ≈2.7 VA Vrms × I Regulation Not specified Typical EI range (assumption) Pinout & Wiring 🧰 Side Terminals Function Primary P1 – P2 220–240 VAC (L/N) Secondary S1 – S2 9 VAC output Performance & Calculations 📊 No‑load DC after bridge: 9·1.414 − ~1.4 ≈ ≈11.3 V . Example capacitor for ΔV=1 V at 0.3 A: C ≈ 0.3/(2·50·1) ≈ 3,000 µF . Applications ⚙️ Small linear DC supplies, logic-level circuits, relays, sensors, and low-power audio preamps. Installation & Safety 🔒 Use primary fuse and proper insulation; keep clearances between primary and secondary wiring. Testing & Commissioning 🧪 Verify 9 VAC at no‑load; check regulation under load up to 300 mA. Videos ▶️ Transformers Explained – The Engineering Mindset: https://www.youtube.com/watch?v=jcY4QN7awEc Bridge Rectifier with Capacitor Filter: https://www.youtube.com/watch?v=EfSW_9lx1VE Bridge Capacitor Value Calculation: https://www.youtube.com/watch?v=J9HsLWmtBnE نظرة عامة 🔌 محول EI صغير يحول 220–240 VAC إلى 9 VAC عند 300 مللي أمبير (≈2.7 VA). ثانوي مفرد (مش 9‑0‑9) . المواصفات السريعة ⭐ المدخل: 220–240 فولت المخرج: 9 فولت AC / 0.3 أمبير قدرة تقريبية: 2.7 VA التوصيلات 🧰 الجانب الأطراف الوصف ابتدائي P1 – P2 دخل 220–240 VAC ثانوي S1 – S2 9 VAC