Electrical Properties, Installations, and Home Automation

Electrical Properties: Conductors, Insulators, and Semiconductors

Electrical properties refer to a material's ability to conduct electrical current. Materials can be classified into three main categories:

• Conductors: Materials that allow electrons to move with little difficulty. Examples include metals.
• Insulators: Materials that significantly resist the movement of electrons. Examples include plastics, ceramics, and wood.
• Semiconductors: Materials whose conductivity depends on temperature and impurities. They can be manipulated to control electrical current.

Electrical Installations

An electrical installation typically consists of the following components:

• General protection box
• General power supply line
• Meter
• Individual bypass

The internal installation includes:

• Control panel (ICMP, ID, PIA, separating different circuits)
• Power circuit
• Earthing

Key Components of an Electrical Installation

• ICMP (Interruptor de Control de Máxima Potencia - Maximum Power Control Switch): A magnetothermic switch that ensures the supplied power does not exceed the contracted amount. It protects the electrical installation.
• ID (Interruptor Diferencial - Differential Switch): Protects people by detecting current leaks.
• PIA (Pequeños Interruptores Automáticos - Small Circuit Breakers): Protect against overloads and short circuits.
• Earthing: Protects against electrical shocks by diverting leakage current to the ground.

Switches and Other Devices

• Switch: A device that opens and closes a circuit, maintaining its state (ON/OFF) until activated again.
• Push-button: Performs the same function as a switch, but only while being pressed. Examples include doorbells and car lights.
• Commutator (Two-way switch): A device with three terminals (one input, two outputs) that allows a circuit to be controlled from two different locations.
• Other devices: Automatic scaling, teleruptors.

Home Automation

Home automation involves using technology to automate and control home systems, improving quality of life and simplifying household tasks. Key elements include:

• Sensors: Capture information such as temperature, motion, or smoke.
• Actuators: Control devices like heating systems or alarms.
• Control unit: Manages the system (can be simple or complex).

Home automation systems can be centralized, distributed, or mixed. Applications include energy management, comfort, security, and communications.

Mechanical Properties: Stress and Strain

Materials are subject to various types of stress:

• Tensile
• Compression
• Bending
• Twisting
• Shearing

Alloys and Steel

An alloy is a product obtained by combining two or more chemical elements, at least one of which must be a metal.

Steel is a pure iron-carbon alloy with a carbon content of less than 0.03%.

Steel Production Procedures

• Forging: A solid mass of hot metal is placed between two halves of a mold or die, and compressive forces are applied to shape it.
• Molding: Molten metal is poured into a closed mold and allowed to solidify.

Steel Acquisition

1. Cast iron is obtained in a blast furnace.
2. Cast iron is used for casting.
3. Cast iron is transformed into steel.

Heat Treatment of Steel

• Tempering: Applied to achieve high hardness and resistance in steel.
• Annealing: Slow cooling to relieve internal stresses.
• Normalizing: Used to refine the grain structure and relieve internal stresses.