Alternating and Direct Current: Motors and Alternators
Production of Alternating Current in a Rotating Coil
The production of alternating current occurs in a coil that rotates within a magnetic field. Each terminal of the coil is connected to a metal ring conductor, where two brushes collect the induced current supplied to the circuit and determine how it is applied externally. For the induced current, the right-hand rule of three fingers is applied.
Rectifying Current Through the Commutator Bars
We get DC current in the generator output. Converting AC
Read MoreElectrical Switchgear and Protection Equipment in Transformer Centers
Transformer Center Switchgear and Elements
1. CT Switchgear and Elements
It’s called electrical facing any equipment or apparatus for controlling the electrical system at will. The cladding, which has indoor or outdoor CT, has the following functions:
- Maneuvers of the circuit.
- Transformation of energy.
- Protection of persons and goods.
To achieve these goals, the enclosure where the switchgear is placed requires additional facilities such as:
- Ground Installation
- Fire Installation
- Ventilation
- Lighting Installation
Thermodynamics: First and Second Laws in Action
First Law: Open Systems
In open systems, there is both mass flow and energy transfer.
Mass Flow
The amount of mass flowing through a system per unit of area, volume, and time. If an open system has conservation of mass, and if the fluid is incompressible, it means that the density at the input is equal to the density at the output.
Work Flow
The work done by the fluid to move through the system. Due to the conservation of energy, the energy input must be equal to the energy output.
Enthalpy
A thermodynamic
Read MoreTelecommunications Circuits, Channels, and Bandwidth
Circuits
A circuit is a communication path between two points, set as transmitter (TX) and receiver (RX).
Lines
A line is the local link connection that interconnects the telephone with the user terminal equipment.
Channels
An UNCA channel is a simple, logical connection for end communication. The channel may transmit voice and data signals.
Networks
A network is a set of interconnected telecommunications elements, properly working in coordination to make the transfer from the TX to the RX.
Dedicated Circuits
Dedicated
Read MoreOperational Amplifier Stages and Circuit Breaker Types
Operational Amplifier (Op-Amp) Stages
An operational amplifier (op-amp) has a general structure with different stages that amplify, buffer, and output the signal. Here is a simplified breakdown of a typical op-amp block diagram and its main stages:
1. Input Stage
- Purpose: This stage takes the differential input (two input signals, inverting and non-inverting) and amplifies the difference between them.
- Components: Usually consists of a differential amplifier, often using transistors or FETs.
- Functionality:
Electrical Circuits: Understanding Key Concepts and Laws
Item 54: Electrical Circuits
Introduction
A circuit or electrical grid is a set of elements combined so that the possibility exists that an electrical current will flow. Depending on the nature of the excitation sources, we obtain several interesting chapters in the study of electrical circuits. If the circuits are time-invariant, they are excited by direct current (DC). If the excitations are sinusoidal functions of time, the circuits are excited by sinusoidal alternating current (AC). The latter
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