LEW study guide
LEW · Work through your exam, one topic at a time.
LEW stands for Licensed Electrician (or Electrical) Worker - a state or jurisdiction-issued credential that authorises a person to perform electrical installation work within that jurisdiction's scope rules. Unlike a purely national trade certificate, licensing is administered locally, so requirements, recognised experience and permitted task scope vary by issuing authority. The LEW study guide has 7 sections and about 2,394 words.
01Electrical Fundamentals and Circuit Theory
Circuit analysis with numbers: Ohm's law and Kirchhoff's laws, series and parallel networks, impedance, AC power in kW, kVA and kvar, power factor, and balanced three-phase relationships. Questions are usually short calculations where unit discipline decides the mark.
369 words, about 2 min02Wiring Methods, Materials, and Installation Practices
Cable and conduit selection, installed current-carrying capacity, derating factors, installation reference methods, voltage drop, and the physical rules for supporting, enclosing and sealing wiring. Coordination: I b ≤ I n ≤ I z, where I b is design current, I n the device rating and I z the derated cable capacity.
363 words, about 2 min03Overcurrent Protection, Grounding, and Bonding
Selection and coordination of protective devices, breaking capacity and discrimination, RCD application, and the earthing and bonding arrangements that make automatic disconnection of supply work. I b ≤ I n ≤ I z and I 2 ≤ 1.45 I z: the device must protect the cable, not only the load.
382 words, about 2 min04Motors, Controls, and Utilization Equipment
Motor circuit design, motor protection and starting, contactor and starter selection, and rules for utilisation equipment such as socket outlets, water heaters and fixed appliances. Two protections are needed: short-circuit protection (MCB or fuse, rated for starting current and fault level) and overload protection (thermal overload relay set to motor FLC, or 1.05 times the service factor current).
330 words, about 2 min05Transformers, Distribution, and Power Quality
Transformer ratings and protection, distribution arrangements, fault levels, and the power-quality issues that affect real installations: harmonics, power factor, neutral loading and voltage unbalance. Transformer size is quoted in kVA; phase current I = kVA × 1000/(√3 × V).
306 words, about 2 min06Electrical Safety, Codes, and Standards
The legal and code framework for electrical work, the limits of a licence, safe isolation and permit-to-work discipline, and the standards underpinning design and inspection. The Electricity Act and the Electricity (Electrical Workers) Regulations set the licensing grades - Electrician, Electrical Technician and Electrical Engineer - with defined scope and voltage limits for each.
333 words, about 2 min07Testing, Inspection, and Troubleshooting
The order and method of inspection and testing, instrument use, interpretation of results, and the diagnostic reasoning used to locate faults. Sequence: visual inspection first, then continuity of protective and bonding conductors, ring final circuit continuity, insulation resistance, polarity, earth fault loop impedance, prospective fault current, RCD operation and functional testing.
311 words, about 2 min