Indepth Electrical engineering

Introduction to Motor Duty Cycles Electric motors do not always operate under the same load or running conditions. In real-world applications, a motor may run continuously, intermittently, or with frequent starts, stops, and braking. These patterns of operation are known as duty cycles , and they directly influence the motor’s heating, cooling, and overall lifespan. International standards (IEC/IS) classify duty cycles into eight standard types (S1 to S8) , helping engineers select the right motor for each application. Types of Motor Duty (S1 to S8) Electric motors are designed to operate under different duty cycles , depending on the application. The duty type defines how long the motor runs, rests, and how heat builds up and dissipates in the windings. Below are the standard duty classifications: S1 – Continuous Duty Motor runs at constant load long enough to reach thermal equilibrium . Example: Pumps, compressors, fans. S2 – Short-Time Duty Motor runs at constant ...

📏 American Wire Gauge (AWG) – Calculations 1. Definition AWG (American Wire Gauge) is a logarithmic stepped system for wire diameters. The smallest common size is No. 36 AWG = 0.0050 in (0.127 mm) . The largest standard size is No. 0000 (4/0) AWG = 0.4600 in (11.684 mm) . The ratio between these two diameters is 92 , across 39 steps . 2. Formula for Wire Diameter The diameter (in inches) of an AWG wire size n is: d n = 0.005 × 92 36 − n 39 d_n = 0.005 \times 92^{\frac{36-n}{39}} n n = AWG size (integer, can be negative for 0/00… sizes). For m/0 AWG (like 4/0), use n = 1 − m n = 1-m . Example: for 4/0, n = − 3 n = -3 . The cross-sectional area (in circular mils) is: A C M = d n 2   ( in mils 2 ) A_{CM} = d_n^2 \ (\text{in mils}^2) or in mm²: A m m 2 = π 4 × d n 2 × ( 25.4 ) 2 A_{mm^2} = \frac{\pi}{4} \times d_n^2 \times (25.4)^2 3. ASTM B 258-02 Standard Successive size ratio = 92 1 / 39 ≈ 1.1229322 92^{1/39} \approx 1.1229322 . Diam...

Slip and Full-Load Speed of Induction Motor What is Full-Load Speed? The full-load speed of an induction motor is the speed at which the motor delivers its rated full-load torque and rated power output. This value is usually specified in RPM (revolutions per minute) on the motor nameplate. Unlike synchronous speed (the speed of the rotating magnetic field determined by supply frequency and pole number), the full-load speed is slightly lower , because the rotor always lags behind the magnetic field. This difference is known as slip . 👉 Example: For a 4-pole motor on 60 Hz supply, synchronous speed = 1800 RPM. At full load, actual rotor speed might be 1748 RPM , and the difference of 52 RPM is due to slip. What is Slip? Slip (s) is the percentage difference between synchronous speed (Ns) and actual rotor speed (Nr). s=Ns−NrNs×100s = \frac{N_s - N_r}{N_s} \times 100 At standstill (startup), slip = 100%. At no-load , slip is very small (0.2–0.5%)....

There are following lighting Zones in Designing lighting system of any area:- Zone Recommended Uses or Areas Zoning Considerations LZ-0 Lighting Zone 0 should be applied to areas in which permanent lighting is not expected and when used, is limited in the amount of lighting and the period of operation. LZ-0 typically includes undeveloped areas of open spaces, Parks , Outside area of any industry . Special review should be required for any permanent lighting in this zone. LZ-1 Lighting Zone 1 pertains to areas that desire low lighting levels. These typically residential communities with low Population, rural town centers, business parks, and other commercial or industrial/storage areas typically with limited night time activity. This zone also Includes agricultural zone districts; rural residential zone districts; business parks; open space include preserves in developed areas. LZ-2 Lighting Zone 2 pertains to areas with moderate lighting levels. ...

Tube lights are part of every industry and household. LED tube-lights are also coming in same sizes that of traditional lights. Diameter of tube-light is described in 1/8 of the inch. So a T8 tube light is 1 inch diameter tube-light. This is obtained by simply multiplying 1/8 by numeric letter of description of tube light.   Sizes of tube lights vary from T2 to T17. Electronic ballasts, and T5 or T16 ( 5 / 8 " Ø or 15.875 mm Ø) for very small lamps which may even operate from a battery powered device. Fluorescent tube diameter designation comparison Tube diameter designations Tube diameter measurements Extra Imperial-based Metric-based Inches Ø  (") Millimeters Ø  (mm) Socket Notes T4 N/A 4 / 8 " Ø 12 mm Ø G5 Bipin Slim lamps, tube lengths may vary T5 T...