Discipline
Electrical
Hazardous area classification, Ex protection types, cable selection and sizing, earthing, motors and lighting.
- Topics
- 9
- Standards covered
- 27
Beginner
No prior knowledge assumed
Hazardous areas — zones, gas groups and Ex protection explained
Why a light fitting in a refinery costs ten times a normal one. Zones and divisions, gas groups, temperature classes, IP ratings, and how to read an Ex certification label.
Cables — construction, selection and why sizing is never just about current
What the layers of a cable do, how power, control and instrument cables differ, the four things that decide a cable size, and why the published rating is never the rating you get.
Lighting and small power — the systems people only notice when they fail
How lighting levels are set and why uniformity matters more than average lux, the three tiers of emergency lighting, and why a socket outlet in a hazardous area is not a simple thing.
Intermediate
Builds on the basics
Earthing and bonding — several different jobs sharing one word
Why a plant has more than one earth, the difference between earthing and bonding, how the neutral earthing decision shapes the whole system, and why static bonding has almost nothing to do with fault current.
Motors and starters — starting current, protection and what actually kills them
Why an induction motor draws six times its rated current on starting, what each starting method trades away, and why nearly every motor failure ends as overheated insulation.
Distribution and the single line diagram — the map of the electrical system
How power gets from the grid to a motor, what transformers and switchgear actually do, why protection must discriminate, and how to trace a supply on a single line diagram.
Switchgear, transformers and protection testing
Why secondary injection proves the relay and primary injection proves everything else, what a reversed CT does to differential and directional protection, why an open CT secondary is dangerous, what breaker timing feeds into, and why phase rotation is checked before anything is paralleled.
Ex installation and inspection — where compliance is actually won or lost
Certified equipment is the easy part. Glands, unused entries, flame paths, IS segregation and the inspection regime are where hazardous area compliance is genuinely decided.
Electrical commissioning and turnover — from dead to live
Why insulation testing needs electronic devices disconnected and readings corrected for temperature, what a functional test proves that a settings check cannot, why an inhibit register exists, why as-left settings are recorded, and what changes the moment a system is energised.