Your distribution board: circuit breaker, RCD and SPD demystified

Every property has a little box with switches that almost nobody understands. When it trips, the usual reaction is to switch it back on and hope. When it gets hot, the usual reaction is to ignore it. This course changes that. You will open the board safely and know what each part does: the main breaker, the circuit breakers, the RCD (residual current device, "DR" in Brazil) that protects people, the SPD (surge protective device, "DPS" in Brazil) that protects appliances against surges, and the busbars that distribute everything. You will understand why a 40 A breaker does not save anyone from an electric shock, why the RCD trips with the electric shower (an instant water heater common in Brazil) and what to do about it. You will learn what NBR 5410:2004 (corrected version 2008), the Brazilian standard for low-voltage installations, asks of a residential board. And you will learn to read the warning signs: repeated tripping, heat, a burning smell, buzzing. There are 6 lessons of about 25 minutes each, with examples from a house, a bakery, a farm, an office and a shop in the countryside of São Paulo state, a field checklist and tasks using your own board. The course starts where EL1 left off: there you learned to do the tripping calculation, tested the RCD and drew the board map; here you understand each part from the inside. The course does not qualify anyone to build a board: it teaches you to understand it, check it and talk to the professional as an equal.