December 2024
- 09: Point-on-Wave (PoW) Switching
- 06: Importance of Surge Impedance Loading (SIL) in Transmission Lines
- 05: Significance of K factor in High VoltageCircuit Breaker Ratings
November 2024
- 25: Philippine Electrical Code – Ambient Correction Factor for Cables
- 21: Philippine Electrical Code – Objectionable Current
- 19: Philippine Electrical Code – General Requirements for Grounding and Bonding
- 18: Philippine Electrical Code – Separately Derived System
- 15: Philippine Electrical Code – Additional Requirements for GFCI Protection
- 13: Philippine Electrical Code Common Violations – GFCI Protection for Kitchens (Other than Dwelling Units)
- 08: Arc-Flash Hazard Analysis – A Requirement of the Philippine Electrical Code
- 07: Philippine Electrical Code Common Violations – Missing or Improper Labeling
- 06: Philippine Electrical Code Common Violations – Working Space Violation
- 05: Philippine Electrical Code Common Violations – Grounding and Bonding Between the Service Disconnect and Feeder Panelboard
October 2024
- 28: Philippine Electrical Code Common Violations – Conductor Box Fill
- 23: Selection of Variable Frequency Drives – Examples
- 22: Selection of Variable Frequency Drives
- 17: Power Factor Correction and Harmonic Resonance: A Risky Combination
- 16: Variable Frequency Drive Cable Length Resonance Frequency
- 14: Effect of Cable Length on Variable Frequency Drive
- 11: PEC, NEC and IEC Comparison of Cable sizes
- 09: Key Differences in Power Transformer Selection According to International Standards
- 03: IEC Current Transformer Accuracy Class
September 2024
- 26: Cooling Methods of Power Transformers and Reference Standards
- 25: Kelvin’s Law and Minimum Conductor Size
- 24: Voltage Selection Guide for Electric Power Transmission Line as to Load and Distance
- 19: Selection of the Insulation Level for Power Cables
- 18: Power Cable Shielding – Benefits, Types and Requirements
- 17: Low Voltage Circuit Breaker Selection Criteria
- 16: Electrical Static Charges and the Need for Bonding
- 06: Ferranti Effect – Causes, Implications and Mitigations
- 04: Operating Transformers in Parallel
August 2024
- 30: 10 Key Considerations for Effective Electrical Design
- 16: Harmonics Limit – What is the difference between the IEC and IEEE?
- 06: Circuit breakers with motor protective characteristics
- 05: Derating of the Rated Service Short-Circuit Breaking Capacity (Ics)
July 2024
- 24: A comparison between XLPE and EPR as insulating materials for HV cables
- 18: Electrical Protection Fundamentals
- 16: High Voltage Arc Flash Assessment and Applications Part 2
- 15: High Voltage Arc Flash Assessment and Applications
- 03: Heat Dissipation in Sealed Electrical Enclosures
- 02: Protection Coordination in Electrical Substation – A Case Study
June 2024
- 27: Substation Earthing Design
- 25: Soil Resistivity and Soil Resistance
- 24: Transmission Line Sag Calculation
- 14: Recommended Protection Relay Grading Interval
- 01: Electromagnetic Interference (EMI) and Electromagnetic Compatibility (EMC)
May 2024
- 21: Selection of AC Short-circuit Protective Devices and Equipment
- 19: Earthing Systems – Design Calculations Analysis
- 16: Comparison Various Earthing System
- 14: Electrical Switching Transients
- 12: Importance of Earthing Only One End of a Cable
- 08: Cathodic Protection Of Offshpre Structures
- 02: Hazardous Area Classification Impact on Earthing Systems in Oil & Gas Installations
- 01: Earthing System in Oil & Gas Installations
April 2024
- 30: Selection of Electric Motor Rating to Match Driven Equipment
- 29: Electric Motors Derating factors
- 26: Transients In Low Voltage Electrical Systems
- 26: Power System Overvoltages and Insulation Coordination – Part 2
- 23: Role of X/R Ratio in Circuit Breaker Short Circuit Duty Evaluation
- 22: Practical Guide to Electrical Grounding
- 19: Power System Overvoltages and Insulation Coordination – Part 1
- 17: Neutral Grounding
- 15: Understanding the Concept of Earthing In Electric Power System
- 03: Compliance to Statutory Laws
- 01: Electrical Engineers and Digital Technologies
March 2024
- 20: Selection of System Voltage
- 10: Low-voltage Circuit Breaker Distribution Systems
- 08: Why Wye-Wye Transformer Connection is Bad?
- 07: System Grounding
- 06: Comparison of Common Induction Motor Starting Methods
- 05: Effect of Voltage on Induction Motor Characteristics
February 2024
- 26: Sign-off on a Marked-up Document
- 23: Compliance to Standards and Statutory Laws
- 22: Voltage Drop Calculations
- 21: The Electrical Engineer and the Electrician
- 20: Importance of Standards in Engineering Design
- 19: Philippine Electrical Code – Acceptable Practice
- 16: Spaces About Electrical Equipment – Working Spaces
- 14: IEEE Transformers Categories
- 13: Philippine Electrical Code – Equipment Grounding and Equipment Grounding Conductors
- 12: The Effect of Earthing Methods
- 09: Normative and Informative Annexes Compliance
- 08: Philippine Electrical Code – Number of Supplies
- 07: Skin Effect Derating Factor on Conductor Ampacity
- 06: Another Reason Why PEC Should Adapt IEC
- 05: When Standards is Withdrawn
- 04: Philipine Electrical Code – Is Design Analysis Required for Dwelling Units?
- 01: Philippine Electrical Code – Temperature Limitation of Conductors
January 2024
- 30: Conductors in Parallel in Acccordance with the Philippine Electrical Code
- 27: Philippine Electrical Code – Multifamily Dwelling Unit, 400/230 Volts Three-Phase 4-Wire Service
- 26: Philippine Electrical Code – Calculation for Multifamily Dwelling Unit, 230 Volts Single Phase Service
- 24: Philippine_Electrical_Code – Feeder or Service Neutral Conductor Size
- 21: Optional Calculations for Dwelling Units – Philippine Electrical Code
- 12: Types of Miniature Circuit Breakers According to IEC 60898-1 Instantaneous Tripping Currents
- 11: Philippine Electrical Code Requirements for Capacitors
- 04: Sub-synchronous torsional interaction (SSTI)
December 2023
- 30: Voltage and Frequency Limits of Electric Motors – IEC 60034-1
- 14: Low Voltage Circuit Breaker Selectivity Categories
- 10: Power-line Surge voltages and Surge Currents – Causes and Effects
- 03: Earth Fault Higher Than Three Phase Fault
November 2023
- 29: Selecting 80% or 100%-Rated Molded Case Circuit Breakers According to Philippine Electrical Code
- 22: Modernization of Electrical Substation Automation Systems Using IEC61850
- 17: Chartered Professional Engineer or a Registered Professional Engineer
- 16: IEC 61850 Changed Electrical Protection, Control and Monitoring
- 15: Electromagnetic Compatibility (EMC) and its Importance in Power Quality
- 14: National Electrical Code (NEC) and IEC 60364 – Electrical Installations for Buildings
- 13: Power System Analysis Software – Required or Not?
- 03: Equipment Selection – Metal-clad or Metal-enclosed Switchgear
October 2023
- 30: Network Protection and Automation Guide
- 25: Earth Leakage Circuit Breaker and Residual Current Circuit Breaker – Application, Operation and Limitations
- 24: Electrical Equipment Duty and Absorbed Power
- 16: ABB Protection Application Handbook
- 12: Selection of Power Circuit Breaker Rating – Part 3
- 10: IEEE/IEC 62271-37-013-2021 – International Standard for High-voltage switchgear and controlgear Part 37-013: Alternating current generator circuit-breakers
- 09: Soft-starter or Variable Frequency Drive – Applications and Differences
- 07: Selection of Power Circuit Breaker Rating – Part 2
- 05: Selection of Power Circuit Breaker Rating – Part 1
- 03: What is a trip free circuit breaker?
September 2023
- 30: A Safety Measure Taken for Granted
- 13: Industrial Power System Design – Selection of System Voltage
- 11: Global Marketability of Filipino Engineers and Other Professionals
- 04: Investment in Solar Power, Is It Worth It?
- 01: Flame Retardant and Flame Resistant Cables – Differences, Applications and Standards
August 2023
- 30: Non-hazardous Area – IEC 60079
- 29: Use of ATEX Certified Equipment
- 28: Global Competitiveness of Engineering Educational System in the Philippines
- 25: AC Power Line Interference onPipeline and its Mitigation
- 24: What is the difference between a metalclad switchgear from metal-enclosed switchgear?
- 23: Battery Rooms – Explosive or Non-Explosive?
- 21: Climate Change – Challenges and Opportunities
- 18: Recommended References on Arc Flash
- 17: What is difference of Arc Fault from Arc Flash?
- 16: What is an arc fault?
- 15: Switchboard Rating for Internal Arcing Fault Clearing Time and Peak Current Withstand
- 14: Recommended References for Power System Design
- 11: IEC 60865 Short-circuit currents – Calculation of effects
- 10: Arc-flash – hazards, mitigations and standards
- 08: Use of Single-Pole Circuit Breaker as Overcurrent Device – Philippine Electrical Code 2009
- 01: Restructuring the Philippine Educational System
July 2023
- 27: Skills Assessment, Evaluation, Resilience and Job Security
- 25: PEE Board Exam April 1991 – First Placer
- 19: Effects of Variable Speed Drive Rectifier Confguration on System Harmonics
- 14: Soil Thermal Resistivity
- 13: Negative Sequence Currents – Causes, Effects and Protection
- 11: What is an infinite bus?
June 2023
- 21: Specification Guide for Electric Motors
- 19: A Filipino Engineer and the Washington Accord
- 15: Ohm’s Law – The Fundamental Principle in Electrical Engineering
- 11: Philippine Electrical Code (PEC) – A Primer
May 2023
- 19: Concrete-Encased Earthing Electrode
- 16: Challenges, opportunities, constraints and innovations
- 15: NEMA Design Letters of Polyphase Squirrel-Cage Induction Motors
- 12: Voltage Classes – ANSI vs IEC
- 11: IEEE 519-2022 Changes from IEEE 519-2014
- 05: Sizing Generator for Motor Starting
April 2023
- 24: How to Protect Your House and Its Contents from Lightning
- 16: Ventilation Requirements for Stationary Battery Rooms
- 14: Selection of Electrical Equipment – Common Rules
- 06: IEEE C57.12.00 – Preferred Continuous kVA Ratings of Transformers
- 04: Complex MVA Method Short Circuit Calculation
- 02: Per-Unit Method Short Circuit Calculation
March 2023
- 25: Short-Circuit Calculations Is Required by Philippine Electrical Code 2017
- 24: Protection Against Electric Shock
- 21: Arc-Fault Circuit Interrupter – NEC 2017 Provision Missing in PEC 2017
- 19: Branch Circuit Maximum Loads according to Philippine Electrical Code 2017 Edition
- 15: A Brief History of Electrical Power Systems
- 14: IEC Standard Voltages
- 12: Identification of Grounded Conductors – Philippine Electrical Code 2017 Edition
- 11: Significant Updates of the Philippines Electrical Code 2017 Edition
- 05: Hazards of Insufficient Short-Circuit Current Rating according the Philippine Electrical Code 2017 Edition
February 2023
- 21: If you don’t know, Ask…
- 18: Variable Frequency Drives Cable Selection
- 16: Paralleling of Generators – Application Guide
- 15: Selection of Circuit Breakers
- 10: Importance of Slip in Induction Motors
- 09: IEEE Std 80 Step Potential and Touch Potential Calculation
- 05: Comparison of NEMA 250 Enclosures and IEC 60529 Degrees of Protection (IP Code)
- 01: Impact of Unbalance Voltage on Induction Motors
January 2023
- 29: CAUTION! Do not mix LV and ELV in Multicore Control Cable
- 28: Implementing Type 2 Coordination to Improve the Performance of the Motor Control Center
- 27: Fundamentals of a Motor Thermal Model and its Applications in Motor Protection
- 24: History of Earthing / Grounding
- 23: Traits of Successful Design Engineers
- 22: Grounded Conductors and Bonding Jumpers for Alternating-Current Systems – Philippine Electrical Code 2017
- 21: Concrete-Encased Electrodes – Grounding Electrode Permitted by the Philippine Electrical Code 2017 Edition
- 18: Renewable Energy Sources
- 17: Low Voltage Three Phase AC Motors Protection – Part 5
- 16: Low Voltage Three Phase AC Motors Protection – Part 4
- 15: Low Voltage Three Phase AC Motors Protection – Part 3
- 14: Low Voltage Three Phase AC Motors Protection – Part 2
- 13: Low Voltage Three Phase AC Motors Protection – Part 1
- 12: Classification of Grounding According to Functions
- 05: IEC 60079 Hazardous Area Zone Classifications
- 04: Arc-Flash Hazard Warning according to Philippine Electrical Code 2017 Edition
- 03: IEC 62305 – Protection against lightning
- 01: Lightning Protection – Rolling Sphere Method Accordning to Philippine Electrical Code 2017 Edition
December 2022
- 28: Non-electrical Methods of Partial Discharge (PD) Detection
- 27: ANSI/IEEE vs IEC Short Circuit Calculations Methodology
- 23: Importance of Project Design Stages
- 22: Electrical Engineer’s Secondary Skill
- 20: IEEE & IEC Comparison – Terms & Jargon
- 18: Is your Solar Panel Installation Compliant to Philippine Electrical Code 2017 Edition?
- 17: Rural Substation Design
- 14: Ground-fault Protection for Personnel In Dwelling Units In Accordance to Philippine Electrical Code 2017 Edition
- 11: Cable Size Selection for Cyclic Loads
- 09: Protection of Electricity Distribution Networks (Energy Engineering) 4th Edition
- 07: Power Electronics Converter Harmonics: Multipulse Methods for Clean Power
- 05: Materials for Lightning Protection in accordance to Philippine Electrical Code 2017 Edition
- 04: Single Family Dwelling Service Disconnecting Means According to Philippine Electrical Code 2017 Edition
November 2022
- 30: Selective Coordination According to Philippine Electrical Code 2017 Edition
- 28: Paralleling Generator Systems
- 26: Circuit Breaker Interrupting Capacity and Short-Time Current Ratings
- 22: Limiting transferred earth potentials
- 19: What is an Effective Grounding?
- 14: Counterfeits Can Kill
- 13: IEEE Std 3002.8 – IEEE Recommended Practice for Conducting Harmonic Studies and Analysis of Industrial and Commercial Power Systems
- 08: IEC 61439 – Relationship between peak current and short-time current
- 07: Philippine Electrical Code – Arc-Flash Hazard Warning Requirement
- 06: Voltage Levels – IEC 61000-3-6
- 05: Application of Maximum and Minimum Short Circuit Currents as per IEC 60909
- 03: Electrical Hazards and Safety
- 02: Philippine Electrical Code – Low Voltage
- 01: Asynchronous (Induction) Motor Data – IEC 60909
October 2022
- 31: PEC Requirement for Ground-Fault Protection
- 25: Circuit Breaker Utilization Categories (IEC 60947-2)
- 24: Renewable Energy sources – Pros & Cons
- 16: The Need for Power System Fault Analysis
- 15: ATEX Certified Equipment
- 13: IEC 62262 – IK Codes – Impact Protection for Electrical Enclosures
- 11: Cable Shield and Outer Sheath Grounding (Earthing)
- 09: Arc Flash Equipment Labeling Requirement
- 06: Which Standard Prevails?
- 05: Estimation of Plant Electrical Load – Part 3
- 04: Explosive Atmospheres – ANSI/ISA/UL/NFPA/EIC
- 03: Equipment Protection Level
- 02: Estimation of Plant Electrical Load – Part 2
- 02: Lightning protection
- 01: Extending Equipment Service Life
September 2022
- 29: Estimation of Plant Electrical Load – Part 1
- 28: Tips on Effective Design
- 27: Short-circuit Apparent Power of the System
- 26: Effect of Utility Fault Level to Low Voltage Equipment Ratings
- 25: Misfits of Design
- 24: Matching the Induction Motor Rating to the Driven Load Power
- 22: Hardwired vs Software Interlocks
- 22: Identification of Conductors And Terminals – IEC 60445
- 20: Miniature Circuit Breaker Applications
- 19: Emergency Lighting Design, Requirement and Compliance
- 18: IEC 60364-5-56 Safety Services (Emergency Systems)
- 17: Design Uniformity Simplifies Replication
- 15: PEC Requirement for Ground-Fault Protection
- 14: Rotating-machine Reactance Multipliers
- 14: Insulation Class and Temperature Rise
- 11: Grid-connected Solar Photovoltaic (PV) System – Need to Know
- 10: Effects of Voltage Variations on Induction Motors
- 07: Effects of Electrical Current to the Human Body
- 06: Arc-flash Hazard Protection – IEC Standard
- 02: Electrical Burns
- 01: Transformer Voltage Regulation
August 2022
- 29: Arc Flash – Calculating Arcing Current
- 25: Protection of the Neutral Conductor
- 21: Effect of Air Density on Equipment Physical Size
- 20: IEC 60076-5 Transformer Impedances
- 18: Earth-fault Factor – Importance in Equipment Selection
- 17: Compliance to NEC Standards and Requirements is not Compliance to NFPA 70E
- 15: Engineering Standards – Do We Need to Comply With Them?
- 14: Application – Fault Sequence Network Connection
- 11: Lightning Protection Of Oil And Gas Industrial Plants
- 10: IEC Motor Protection Coordination
- 09: IEEE 399 – Recommended Practice for Industrial and Commercial Power Systems Analysis
- 08: Arc Flash – Hazard and System Grounding
- 07: Arc Flash – Incident Energy at Working Distance
- 07: Lightning Damage to Services
- 06: Power Factor Correction and Power System Energy Efficiency
- 04: Short-circuit apparent power of the system
- 03: Life Without Electricity
- 02: IEEE / IEC Oil-immersed Transformers – Methods of Cooling
- 01: IEC 60909 vs ANSI/IEEE 141 Short-Circuit Current Calculations
July 2022
- 31: Fault Sequence Network Connections
- 28: Motor Cable Selection Chart Explained
- 26: Modes of Operation – Variable Speed Drives
- 24: System Voltage Classes (ANSI)
- 21: Electrical Power System Studies
- 20: Protection Against Electric Shock – Indirect Contact
- 18: IEEE and IEC Interface
- 17: IEC 60038 – Voltage Standardization
- 13: Motor Protection -Direct Temperature Sensing
- 12: A Junction Box Is Required
- 09: Open Circuit Faults
- 06: Importance of Design Documentation
- 04: Common Mode Voltages: Causes, Effects and Mitigation
- 02: Cable Rating Reduction Factor due to Harmonic Currents
- 01: Harmonics and Neutral Currents
June 2022
- 30: What is the Allowable Harmonics In the Philippines?
- 29: Engineers Need Actual Site Experience to Do Effective Design
- 29: Greenfield and Brownfield Projects
- 28: Lightning Damage to Structures
- 26: Concept Selection or Detail Design
- 25: Differential Protection – Fast and Reliable
- 24: IEC 61439-1 Minimum Size for PE, PEN Conductors
- 23: Conductor Stranding – IEEE vs IEC Standards
- 22: GMD, GMR and Waterfall Charts
- 20: Three Elements of Good Engineering Design
- 19: Insulation Testing
- 18: International Standards as PEC Alternatives in Electrical Installation in the Philippines
- 16: Electrical Protective Devices and Their Applications
- 15: Low Voltage Fuses Applications
- 14: Insulation Coordination – Why is it required?
- 13: Compliance to Standards is not necessarily compliance to Legislations
- 12: PEC Requirements for Design Analysis Report
- 11: RA 7920 Regulating the Practice of Electrical Engineering in the Philippines
- 10: RA 7920 Provision on Signing of Technical Documents and Drawings
- 09: Effects of Temperature On Cables – Faulty Electrical Wiring
- 09: Calculating Utility Source Impedance
- 08: Circuit Breaker Time-Current Characteristic Curve Made Easy
- 07: Advantages of Per Unit and Percent Calculations
- 06: Symmetrical Components – The Beginning
- 04: Safety in Design
- 02: Why The PEC Needs to Adapt IEC
- 01: Once an Engineer, Always an Engineer
May 2022
- 28: PEC – Is Voltage Drop Calculation Required?
- 26: The Purpose of Maximum and Minimum Short-circuit Currents
- 25: Calculation of Maximum and Minimum Short-circuit Currents
- 24: Comparison of IEC and ANSI Terminology
- 21: Transformer K-factor Rating and Variable Speed Drives
- 19: Old School Method Rocks (Do not be an Idiot)
- 17: Transformer K-Factor Rating and Harmonics
- 14: 10 Reasons to Use Per unit
- 10: Circuit Breaker Ratings – A Primer for Protection Engineers
- 08: Determining the required sizes of earthing conductors and earth electrodes
- 07: Effects of Unbalance Voltage on Induction Motors
- 05: When the Basis of Design Fails to Serve its Purpose
- 03: Effects of Harmonics on Resistive Loads
- 02: Phase Shifting Transformers to Cancel Harmonics
- 01: Phase Sequence of Harmonics
April 2022
- 29: Harmonics and Power Quality
- 28: Introduction to Harmonics
- 27: Ground and Bonding – What is the Difference?
- 26: Time-Current Curves Using Excel
- 25: Effects of harmonics on Electrical Equipment
- 24: Three Phase Voltage Unbalance – Causes, Effects & Mitigation
- 23: IEC Equipment Voltages
- 17: Resistance of Earth Electrodes in Parallel
- 16: Resistance of a Single Earth Electrode
- 08: Isolation of Neutral Conductor in Hazardous Areas
- 03: Philippine Electrical Code – Working Spaces
March 2022
- 31: Philippine Electrical Code – Metal Underground Water Pipe as Grounding Electrode
- 30: Philippine Electrical Code – Equipment Grounding, Grounded and Neutral Conductors
- 21: Electrical Connections Temperature Limitations – Philippine Electrical Code
- 19: Republic Act No 11285 – Energy Efficiency and Conservation Act (Part 4)
- 17: Republic Act No 11285 – Energy Efficiency and Conservation Act (Part 3)
- 16: Republic Act No 11285 – Energy Efficiency and Conservation Act (Part 2)
- 13: Republic Act No 11285 – Energy Efficiency and Conservation Act (Part 1)
- 10: Advantages of High Resistance Grounding Over Ungrounded Systems
- 05: Philippine Electrical Code 2017 – Interpretation
February 2022
- 27: Low Voltage Motor Protection Coordination Using Excel
- 26: Electrical Permits – PEC 2017 Provision
March 2020
January 2020
November 2019
October 2019
September 2019
November 2018
September 2018
- 16: Arc Flash Incident – 13.8 kV Indoor Switchgear
- 07: Objectives of Grounding System
- 05: Grounding and Bonding Permitted Methods
May 2017
April 2017
April 2016
November 2015
October 2015
July 2013
December 2011
July 2011
June 2011
October 2009
January 2009