UPDA Electrical/Electronic Engineering Review 01

Alternator and Synchronous Motor Functioning

• An alternator is over-excited when operating at a leading power factor.
• A synchronous motor operates at over-excited conditions when at a leading power factor.

Antenna and Scheduling Concepts

• A micro antenna is defined as a short antenna.
• Fast track scheduling aims to avoid future cost increase in projects.

Harvard Architecture

• Harvard Architecture features separate code and data spaces.

Electrical Fundamentals

• Force acting on a moving charge in a magnetic field is always perpendicular to both the magnetic field and the direction of the charge's motion.
• The unit of conductance is expressed in mho (inverse ohm).

Engineering Accreditation

• ABET stands for Accreditation Board for Engineering and Technology.

Circuit Analysis

• At very high frequencies, phase shift of a transfer function can reach -90°.
• The third harmonic frequency can be calculated from a given waveform, with values such as 250 Hz or 750 Hz, among others.

Transformer Operation

• Successful parallel operation of transformers requires correct polarity, equal per unit impedance, and identical voltage and frequency ratings.

Logic Gates

• A NOR gate outputs HIGH only when all inputs are LOW.

Digital Communication

• Connection-oriented service in digital telecommunication is provided by ATM (Asynchronous Transfer Mode).

Modulation Techniques

• The commercial method for AM modulation is DSB-LC (Double-Sideband Large Carrier).

Integrated Circuit Behavior

• In NMOS inverters, R-pull up should have a large width-to-length (W/L) ratio for optimal performance.

Real-Time Operating Systems

• A basic real-time kernel should provide task scheduling, dispatching, and inter-task communication.

Signal Classification

• A communication signal classified with a bandwidth of 2 kHz is categorized as narrowband VLF.

Induction Motor Concepts

• Induction motors at no load generally have a slip of around 1-2%, with minimum voltage regulation occurring at unity power factor.

Cable and Resistance Evaluations

• Effective resistance can be achieved by combining resistors: for example, a mix of series and parallel configurations can yield specific resistance values like 4Ω.

Harmonic Frequency Analysis

• Harmonics arise in systems primarily due to variable impedance loads and power electronics loads.

Project Management and Operations

• Fast-tracking projects entails initiating work before design completion.
• Proper response to new work scopes in engineering involves notifying superiors before taking action.

Amplifier Characteristics

• The output impedance of a cascade amplifier should be high to minimize loading effects.

Electrical Characteristics

• In electric circuits, the unit of current is defined as Ampere.

Power Consumption and Motor Operation

• The most economical method to start a single-phase motor typically exploits a split-phase technique.
• Transformer humming is largely attributed to vibrations in core lamination.

Cable Specifications

• The standard wire gauge for earth wires is usually set between 8 SWG and 20 SWG.

Heat Loss and Current Calculations

• Heat loss in conductive materials can be affected by resistance. Halving resistance results in reduced power dissipation.

Feedback Systems in Amplifiers

• Gains can be affected by negative feedback, which alters the overall amplification characteristics.

Project Completion and Scheduling

• The completion time for projects is closely monitored using node networks, ensuring all tasks meet defined timelines.

Signal Propagation

• Signal speed in cables can be assessed through the time of the signal return and cable length.

Antenna Characteristics

• Effective aperture of antennas is crucial for determining required amplifier power and efficiency in radiation patterns.### Electrical Concepts and Principles
• Anions transfer to cations and positive electrodes transfer to negative electrodes.
• Dummy activities are used in diagrams to prevent precedence issues caused by parallel, burst, or merge activities.

Electrical Engineering Calculations

• Average value of signal ( v(t) = 5 \sin(377t) ) is ( 3.2V ) calculated using ( V_{avg} = \frac{2V_m}{\pi} ).
• For a 3-phase transformer rated at 25MVA, with an impedance of 8%, the per unit impedance on a 100 MVA basis is ( 0.32 ).
• The appropriate resistance needed for a DC voltmeter with coil resistance of ( 150 \Omega ) and a sensitivity of ( 10,000Ω/V ) is ( 1MΩ ) in series.

Electrical Generators and Fuses

• An alternator's power factor depends on the rotor speed, core losses, load, and armature losses.
• High Rupturing Capacity (HRC) fuses are designed to safely interrupt large fault currents.

Project Management

• The first step in scope planning is defining objectives and requirements that satisfy customer needs.
• The forward pass in project network calculations determines the earliest start and finish times of activities.

Signal Processing and Communication

• Channel capacity can be calculated using ( BW \log_2(1 + S/N) ).
• The maximum number of ways to transmit 4 bits of digital signals is ( 16 ).

Electromagnetism and Circuit Theory

• The effect of increasing current withdrawal from a battery generally decreases the battery capacity due to polarization.
• A low-pass filter allows low frequencies to pass while attenuating high frequencies.

Motor and Transformer Specifications

• Synchronous motors operating at a leading power factor but no mechanical load are known as synchronous condensers.
• The turns ratio for delta-wye transformers can be calculated by the voltage on the high and low sides.

Semiconductor Devices and Amplifiers

• BJTs (Bipolar Junction Transistors) amplify in the active region and act as switches in the saturation region.
• The voltage gain of an amplifier with feedback can be calculated as the gain without feedback divided by ( (1 + \text{feedback fraction}) ).

Circuit Elements

• For a series system, total resistance is the sum of individual resistances, while for parallel systems, the equivalent resistance can be calculated using the reciprocal sum of individual resistances.
• The properties of a Zener diode in regulation circuits are influenced by its dynamic resistance and input current.

Maintenance and Testing in Engineering

• Software maintenance includes adaptive, corrective, perfective, and customer-initiated maintenance types.
• Integration testing is crucial for ensuring that different software modules function correctly together.

Miscellaneous Engineering Facts

• Humming in transformers is primarily caused by vibrations in core lamination.
• An underground distribution system's insulation is designed for standard voltage levels related to fault analysis.

Environmental and Regulatory Aspects

• Effective earthing mixtures include lime-sand, sawdust-sand, and coal-salt mixtures for optimal conductivity and moisture retention.

General Knowledge

• The key stages in a project life cycle include concept, initiation, planning, execution, and delivery/closure.
• Standard wire gauges for earth wires vary, with common sizes ranging from 20 SWG to 8 SWG, indicating their current-carrying capability.### HDL Based Digital Systems Challenges
• Arithmetic multiplication is challenging to synthesize with HDL.
• Sequential generation of partial products is a method for multiplication.
• Hardware-intensive simultaneous generation of partial products is another method.
• Booth's algorithm reduces complexity by minimizing partial products.
• Sequential right shifts of arguments is not typically used for this challenge.

OP-AMP Input Impedance

• Inverting amplifier input impedance is zero.
• Non-inverting amplifier input impedance is ideally infinite.

OP-AMP Output Impedance

• Inverting amplifier output impedance is ideally zero.
• Non-inverting amplifier output impedance is low but not zero.
• Output resistance of non-inverting amplifiers is the same as the input resistance.

Circuit Breakers

• Air Circuit Breakers are commonly used at the distribution level.

BJT vs MOSFET

• MOSFET transistors depend more on geometry.
• MOSFET transistors provide higher amplification.
• MOSFETs consume no power at input, while BJTs require biasing.

Data Network Characteristics

• Packet-switched networks include source and destination in each packet.
• Packets can travel different paths, highlighting flexibility.
• Transparency of address coding is characteristic of packet-switched networks.
• Packets containing only information bits are incorrect for such networks.

Nyquist Sampling Theorem

• Aliasing is avoided when the highest signal frequency is less than half the sampling frequency.

Power Doubling

• Power doubling results in a decibel increase of 3 dB.

Frequency Division Multiplexing

• In optical communication, FDM is referred to as Wavelength Division Multiplexing (WDM).

Total Quality Management (TQM)

• TQM stands for Total Quality Management.

Intersymbol Interference

• Intersymbol interference mitigation can be addressed with the Nyquist Criterion.

Common Liquid Metals

• Mercury (Hg) is a commonly known liquid metal at room temperature.

Alternator Power Factor

• Power factor in an alternator is influenced by its load conditions.

Circuit Reliability

• Combined reliability of two components is calculated using their individual reliability values.

Variable Resistance and Current Relationship

• Resistance variation produces a specific current-voltage relationship represented graphically.

Interdisciplinary Nature of Engineering

• Engineers benefit from training in multiple engineering fields for interdisciplinary projects.

Induction Machine Slip Frequency

• For a 50 Hz induction machine, a no-load speed of 2900 RPM indicates a slip frequency.

GSM Network I/P Side

• The I/P side of GSM networks typically requires a band pass filter.

Advanced Embedded System Power Consumption

• Reducing power in advanced embedded systems can involve techniques like voltage sensing.

Regression Models

• Not all regression models are linear; specific models can deviate from this.

Speed and Power in Circuit Devices

• ASICs are faster and consume less power, suitable for large-scale projects.

Block Functionality in Circuit Design

• Various components in circuit design serve specific amplification purposes based on frequency.

Work Breakdown Structure (WBS)

• The highest element in a WBS hierarchy is the overall project.
• Work packages are the smallest components in WBS.

DSP Architecture for Operations

• DSPs designed for FFT operations benefit from fixed-point multipliers with wider data paths.

Logic Gate Fan Out

• Fan out refers to the number of gates a single logic gate can drive.

Project Task Management

• Conducting a project is organized through task splitting, resource estimation, and scheduling.

Event Timing in Projects

• Project control spans the entire timeline of the project, from initiation to closure.

Signal Measurement Devices

• Voltmeter is used primarily for measuring potential difference in electrical systems.

Economic Indicators in Project Analysis

• Payback period calculations help assess financial viability for project investments.

Circuit Element Relationships

• Relationships between voltage and current are aligned with Ohm's Law in specific diagrams.

System Resilience in Electrical Networks

• Resilience refers to the capacity of the power system to withstand disturbances.

Crystal Resonance in Oscillators

• Oscillator circuits utilizing crystals operate at specified resonant modes.

Sustainability in Engineering

• Sustainability encompasses economic, social, and environmental components, being equally significant.