Electrical equipment guides
Practical guides from our engineers on choosing, sizing and specifying motors, panels, transformers, batteries, inverters, solar equipment, pumps and cables for Indian industry.
Protection Relays: Overcurrent, Earth Fault, Motor
A practical overview of overcurrent, earth fault and motor protection relays: what each function does, how IDMT curves and grading work, and what to specify when…
7 min readTransformers & Power QualityCurrent and Potential Transformers: Ratio, Burden, Class
Plain-language guide to current and potential transformers: ratio, burden, accuracy class for metering and protection, 1 A versus 5 A secondaries, and the mistakes that cause…
7 min readTransformers & Power QualityIndustrial Earthing: Earth Pits, Electrodes and IS 3043
A practical guide to earthing in industrial plants: electrodes, earth pits, strips and conductors, resistance testing and what the IS 3043 code of practice covers in…
7 min readTransformers & Power QualityTransformer Cooling Classes: ONAN, ONAF, AN, AF Explained
What the four-letter cooling codes ONAN, ONAF, AN and AF mean, how fans change the rating, and how to choose a cooling class for oil-immersed and…
7 min readTransformers & Power QualityPower Factor Correction in India: Billing and How to Fix
What power factor is, how it affects your DISCOM bill and transformer loading, and how to size and select capacitors, APFC controllers and detuned reactors for…
6 min readTransformers & Power QualityCompact Substation: What Is Inside and When to Use One
What a compact or packaged substation contains, how it differs from a conventional civil substation, when it makes sense and what to specify before you order.
6 min readTransformers & Power QualityCast Resin vs VPI Dry-Type Transformer: Which One?
How cast resin and VPI dry-type transformers differ in winding construction, dust and humidity tolerance, fire class and cost, and which suits a plant, a basement…
6 min readTransformers & Power QualityHow to Size a Distribution Transformer for a Factory
A step-by-step method to size a 11 kV/415 V transformer for a factory or building, with a worked example, standard kVA ratings and the mistakes that…
6 min readTransformers & Power QualityTransformer Vector Groups: Dyn11, Dyn1, YNyn0 Explained
Decode the vector group on a transformer nameplate: what Dyn11, Dyn1 and YNyn0 mean, how the 30 degree phase shift works and why it matters for…
6 min readTransformers & Power QualityOil-Immersed vs Dry-Type Transformer: How to Choose
A practical comparison of oil-immersed and dry-type transformers for Indian factories and buildings: where each fits, what each costs you in upkeep, and the questions that…
6 min readSwitchgear, Panels & ProtectionChoosing Push Buttons, Timers and Relays for Control Panels
Push buttons, pilot lamps, timers and interface relays look simple, but wrong colour codes, coil voltages and contact types cause real faults. Here is how to…
6 min readSwitchgear, Panels & ProtectionDrawout vs Fixed Type MCC and Intelligent MCC
Fixed MCCs cost least, drawout MCCs cut downtime, and intelligent MCCs add data. Here is how to decide which construction your plant actually needs.
6 min readSwitchgear, Panels & ProtectionSurge Protection Devices Type 1, 2 and 3: Where Each Goes
Type 1 SPDs handle direct lightning current at the service entrance, Type 2 sit at distribution boards and Type 3 protect sensitive equipment. Here is where…
6 min readSwitchgear, Panels & ProtectionAMF Panel and DG Changeover: How It Works
An AMF panel starts the DG set and shifts load when the mains fail, then reverses it when power returns. Here is the sequence, the hardware…
6 min readSwitchgear, Panels & ProtectionContactor and Overload Relay Selection for Motor Starters
Pick the contactor by its AC-3 rating and duty, set the overload relay to the motor full load current, and protect both with the right short-circuit…
6 min readSwitchgear, Panels & Protection11 kV MV Switchgear and VCB Panels Explained
An 11 kV panel is a metal-enclosed lineup built around a vacuum circuit breaker. This guide covers its parts, ratings, protection and what to specify.
6 min readSwitchgear, Panels & ProtectionBus Duct vs Cables for Power Distribution
Bus duct costs more per metre than cable but wins on voltage drop, space and flexibility at high currents. Here is how to compare them and…
6 min readSwitchgear, Panels & ProtectionACB vs MCCB vs MCB: Choosing the Right Breaker
MCB, MCCB and ACB overlap in the middle of their ranges. This guide compares them on current, fault rating, trip settings and use, and shows how…
6 min read