Electrical Measurement & Lighting Essentials
Tension or Measures of Potential Difference
a) Measure the voltage or potential difference (volt) measured tension. This is formed inwardly by a coil with many turns and a small section, resulting in large internal resistance. It is connected in parallel. Voltmeters are used to measure three-phase switches.
Measures of Intensity (Ammeter)
b) Measures the current. It consists of a coil with few turns and large sections. Its connection is in series to measure the desired intensity. Three-phase switches
Read MoreThree-Phase AC Generators and Induction Motors
(05) Engines: 3f-2 Phase Systems
General Concepts
A three-phase AC generator consists of three alternating electromotive forces (EMFs) with a 120-degree electrical phase delay between them. These are called phases and designated as R, S, and T.
A system is balanced when frequencies and RMS values are equal, and phases are symmetrically out of phase.
If impedances differ, causing different phase currents, it’s an unbalanced system, even with balanced voltages.
Advantages include simpler energy transport
Read MoreEmergency Response Codes: Fire, Rescue, and Communication
Central Alarm
Mute Transmissions: 0-0
Extend ERP Report: 0-1
Consulted and Informed: 0-2
Change Repeat: 0-3
It is…: 0-4
Indicate Location: 0-5
Refer to Place Without Warning: 0-6
Reach Place Without Warning: 0-7
Out of Service: 0-8
Service: 0-9
Return to Barracks: 0-10
Guard at Headquarters: 0-11
Required to Place
Carabineros: 1-0
Air Support: 1.1
Ambulance: 1.2
Community Emergency Office: 1.3
Publicly Shown (Essal, Saesa, etc.): 1.4
CONAF: 1.5
Guard Commander: 1.6
Captain of the Guard: 1.7
Technical Studies Department:
Fundamentals of Electricity and Electrical Installations
Atoms and Electric Charge
An “atom” is the smallest part of a chemical element that retains its properties. “Electric charge” is the excess or defect of electrons in a body.
Electricity and Current
“Electricity” is the orderly movement of electrons through a material. “Sense of electricity” is the direction of moving electrons.
Classes of Electric Current
- Direct current (DC): The flow is constant and does not change direction.
- Alternating current (AC): The electron flow is variable and changes direction.
Power Electronics Devices: A Comparison
BJT vs. MOSFET
Question 20: Differences in characteristics of gate BJTs and MOSFETs?
High-power bipolar junction transistors (BJTs) are common in power converters operating below 10 kHz, handling up to 1200V and 400A. A BJT has three terminals: base, emitter, and collector. In a common emitter configuration, it typically functions as a switch.
An NPN transistor turns on when the base voltage exceeds the emitter voltage, and sufficient base current drives the transistor into saturation. The transistor
Read MorePreamplifier and Power Amplifier Guide: Understanding Audio Components
Preamplifier
A preamplifier consists of several amplification stages that raise the weak input signal from a source to a sufficiently high level.
Input Selector
The input selector adapts the preamplifier’s input to the specific characteristics of the selected audio source (analog or digital).
Preamp Adapter and Level/Impedance
This stage adapts the input level, impedance, and sensitivity to deliver an output signal with suitable amplitude for the main preamplifier input.
RIAA Preamplifier
This component
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