Electrical Components: Types and Functions
Generators
Generators are operators capable of transforming various forms of energy into the electrical energy required to operate different types of automatic and electronic devices.
Batteries
A battery supplies electrical energy through the conversion of chemical energy stored in a substance that leads to the interior.
Ohmic Resistance
Ohmic resistances are electronic components that offer a certain opposition to the flow of electrical current, producing a “fall” of tension between its extremes, called terminals or hooks.
Types of Resistors
a) Fixed resistors: Their face value is constant.
- Agglomerated: These are composed of a mixture of graphite, resin, and talc. Typically, values are high, but they are thermally unstable. If they heat too much, the resistance value can change permanently.
- Carbon film: These are built from a small ceramic cylinder insulator. They are the most used due to their high thermal stability.
- Coil: On an insulator, usually porcelain, a thread of high resistivity alloys such as nichrome or constantan is wound. The set is covered with a layer of glazed enamel. They are used in high-power circuits.
b) Variable resistors: Their ohmic value can be changed at will.
- Coil (rheostats): These are formed by a thread of a certain resistance wrapped in a ceramic support on which a movable contact slides with a cursor. The whole structure is glazed except where the cursor slides. The magnitude of the resistance of the rheostat varies depending on the position of the cursor, allowing for more or fewer turns.
- Carbon film: A carbon film deposited on a crowded support travels on which a cursor slides. By changing its position, the resistance value varies. It is used to vary the intensity of light from a lamp, the speed of an electric motor, the volume on an amplifier, or to control small currents on the order of milliamperes, such as tuning channels.
c) Special Resistance: Their face value can be changed under certain lighting conditions.
Condensers
A condenser is an electronic component that stores electrical charges for a short period of time before releasing them to the circuit later. They are used in many electronic assemblies to eliminate “noise” in audio equipment, filter voltages in power supplies, measure time, and tune in radio stations and channels on radio and television. (Capacity is measured in farads).
Types of Capacitors
A) Fixed capacitors with non-polarized dielectric
- Mica-Capacitor
- Ceramic capacitor
- Paper capacitor
- Plastic capacitor
B) Fixed capacitors with dielectric or electrolytic polarized: Their capacity value is constant. An electrolytic capacitor cannot be connected with the polarity reversed because it can explode.
- Aluminum capacitor
- Tantalum capacitors
C) Variable or Enhancements: Their capacity value can be varied at will. They are formed by a series of parallel fixed armors and another group of mobile armors.
Rated voltage of a capacitor: The voltage value that a capacitor can withstand without suffering defects.
Switches and Commutators
Switches and commutators are operators that maneuver and control electric current, allowing or preventing its passage through a circuit by closing or opening it, respectively. The basic difference between them is the number of output terminals they have. Regarding the switch, it derives the input current of a specific circuit, leaving the others open.
Relays
A relay is a maneuvering operator that controls electric current, allowing it to switch its output terminals, i.e., changing from one terminal to another, depending on the current that reaches its access terminal, thereby controlling one or more channels simultaneously.
A relay is an electromagnetic switch in which the metal contacts are moved by the action of the magnetic field generated by an electromagnet.
Relay Components
a) The excitation circuit is formed by a coil of conductive wire wound around an iron core. While the coil is not supplied with voltage, the relay is considered “at rest”.
b) The switching circuit is composed of a foil insulated from the coil that, when triggered by the moving part, opens and closes circuits connected to its terminals.