ITI Solar Technician Electrical (AITT Theory) study guide
ITI Solar Technician Electrical (AITT Theory) · Work through your exam, one topic at a time.
The ITI Solar Technician Electrical trade theory paper is the All India Trade Test (AITT) theory assessment taken by trainees who have completed the NCVT-recognised Solar Technician (Electrical) trade under the Craftsman Training Scheme. It tests whether a trainee can reason about solar photovoltaic work the way a working technician must: reading a circuit, selecting and connecting modules, sizing a battery bank and inverter, commissioning a rooftop system safely, and diagnosing faults afterwards. The ITI Solar Technician Electrical (AITT Theory) study guide has 15 sections and about 4,002 words.
01Electrical Fundamentals
This domain tests the basic quantities and laws that every solar PV electrical task depends on: charge, current, voltage, resistance, power, energy, and series/parallel networks. Expect numerical questions using Ohm's law and Kirchhoff's laws.
286 words, about 1 min02DC/AC Circuits and Measuring Instruments
This domain checks DC circuit analysis and single-phase AC quantities, plus correct use of ammeters, voltmeters, wattmeters, energy meters, multimeters and clamp meters. For a sine wave: V rms = 0.707 × V peak; V avg = 0.637 × V peak; form factor = 1.11; peak factor = 1.414.
299 words, about 1 min03Basic Electronics
This domain covers passive components, their markings, and simple electronic circuits: resistors, capacitors, inductors, transformers, diodes, transistors, rectifiers and filters. Resistor colour code: Black 0, Brown 1, Red 2, Orange 3, Yellow 4, Green 5, Blue 6, Violet 7, Grey 8, White 9; gold ±5%, silver ±10%.
254 words, about 1 min04Semiconductor Devices and Power Electronics
This domain tests PN junctions, diodes, transistors and the switching devices used in charge controllers and inverters: SCR, TRIAC, MOSFET and IGBT. A PN junction conducts when forward biased; silicon drops about 0.7 V, germanium about 0.3 V.
267 words, about 1 min05Electrical Wiring, Installation, Protection and Earthing
This domain tests selection and installation of cables, switches, protective devices and earthing as applied to PV AC and DC circuits. Indian flexible cable colour code: phase red/yellow/blue, neutral black, earth green or green-yellow.
281 words, about 1 min06Solar Photovoltaic Fundamentals
This domain tests how sunlight becomes DC electricity, the meaning of irradiance and insolation, standard test conditions and the factors that change module output. PV effect: photons with sufficient energy release electron-hole pairs in a semiconductor, producing current.
251 words, about 1 min07Cells, Modules and Arrays
This domain tests the series-parallel build-up from PV cell to module to array, including voltage/current relationships, bypass diodes and mismatch. A crystalline silicon cell produces about 0.5–0.6 V; current depends on cell area and irradiance.
279 words, about 1 min08Solar PV System Components: Batteries, Charge Controllers and Inverters
This domain tests battery capacity and care, charge-controller choice, and inverter sizing and output quality. Battery capacity in Ah depends on the discharge rate; C10 means capacity at a 10-hour discharge.
251 words, about 1 min09Solar PV System Design, Sizing, Load Estimation and Energy Yield
This domain tests the design chain: load sheet, daily energy, peak sun hours, array and battery sizing, and expected yield. Build a load sheet: watts × hours per day = Wh/day for each appliance.
276 words, about 1 min10Installation, Commissioning, Testing and Maintenance of Solar PV Systems
This domain tests site practice: mounting, orientation, cable management, commissioning tests and preventive maintenance. Mount modules with correct tilt and azimuth, clear of shade; keep minimum roof clearance for ventilation.
253 words, about 1 min11Electrical Safety, First Aid and Fire Prevention
This domain tests safe isolation, shock response and fire action for electrical and PV installations. Isolate, lock out/tag out, prove dead with a tested voltage tester, and earth or discharge where required before work.
264 words, about 1 min12Solar Energy Applications
This domain tests the main uses of solar energy beyond simple rooftop lighting: thermal systems, pumps, street lights, dryers and hybrid systems. Solar thermal systems convert sunlight to heat; efficiency is thermal, not electrical.
279 words, about 1 min13Net Metering and Grid Interconnection
This domain tests how a grid-connected PV system safely parallels with the utility and how net metering credits import and export. Grid-tie inverter must synchronise voltage, frequency and phase with the grid before connecting.
256 words, about 1 min14Engineering Drawing
This domain tests reading and producing electrical and PV drawings: orthographic views, scales, line types, dimensioning, symbols and single-line diagrams. First-angle projection is standard in India: the object is between the observer and the plane, so the top view is placed below the front view and the left-side view on the right.
256 words, about 1 min15Trade Calculation and Estimation
This domain tests quantity and cost estimation for PV jobs: bill of materials, labour, taxes, energy yield, savings and payback. Estimate from a load list and a single-line diagram; include modules, inverter, mounting, DC/AC cables, isolators, protection, meter, earthing and labour.
250 words, about 1 min