Electrical Circuits, Components, and Energy Principles

Types of Electrical Circuits by Application

• Power Circuits: Used for high-power applications, such as industrial ovens.
• Lighting Circuits: Designed for local electricity supply and residential housing.
• Safety and Emergency Circuits: Engineered to remain operational during power supply faults.
• Auxiliary Power Circuits: Provide necessary energy for critical situations, such as operating rooms, during power outages.

Types of Circuits by Function

Power Circuits: Systems where all energy is transformed into work, typically involving very high intensity.

The Transformer

Transformers are elements used to increase or decrease voltage, consisting of:

• Core: Responsible for separating the transformer parts.
• Two Separate Coils: Winding threads designated as primary and secondary windings (coil 1 and 2).

Formula: V1/V2 = N1/N2 (where N represents the number of turns).

Relays

An electromagnetic operator consisting of two elements:

• Electromagnet: Operates with small quantities of current.
• Switch: Turns on or off depending on the flow of current through the electromagnet.

Relays are used to govern high-power systems using low-power control devices.

Effects of Electric Current

• Thermal Effect: Every conductor heats up when current flows through it.
• Magnetic Effect: Any electrical current creates a magnetic field around a conductor, detectable by a compass.
• Chemical Effect: Electric current breaks down substances, such as acids and salts, when dissolved or melted.

Methods of Producing Electricity

• Friction: Rubbing two bodies together results in an accumulation of charges. When the potential difference is high enough, an electric shock occurs upon contact.
• Chemical Reactions: When two metals are immersed in an appropriate solution and connected by a wire, an electric current is generated.
• Electromagnetic Induction: Moving a conductor within a magnetic field induces an electric current.
• Photoelectric Effect: Some metals emit electrons when light falls on them; if these electrons circulate through a conductor, an electric current is obtained.
• Heating (Thermoelectric Effect): Heating the junction of two dissimilar metals generates a small electrical voltage.
• Pressure (Piezoelectric Effect): Stretching or compressing certain materials creates small voltages on their surface.