FAULT CURRENT
Understanding Available Fault Current
What "available fault current" actually means at a service entrance — and why utility data matters.
FIELD NOTE · 18 MIN
FIELD NOTES
Short technical writing
Plainspoken explainers on power systems concepts. Each note connects back to a lab you can actually run.
FIELD NOTES
NETA: What NETA Testing Verifies
A practical look at what acceptance and maintenance tests are really checking for.
NETAAcceptance TestingMaintenance TestingPower SystemsElectrical Testing
FIELD NOTE · 22 MIN
NEC
NEC Continuous vs Noncontinuous Loads
Learn when the NEC 125% rule applies, when it doesn't, and how to separate continuous and noncontinuous loads without bad math.
NECLoad CalculationsContinuous LoadsOCPD SizingConductors
FIELD NOTE · 22 MIN
PROTECTION
Why Relay Coordination Matters
Selectivity, miscoordination, and how a single bad setting can turn a local fault into a larger outage.
ProtectionRelay CoordinationSelectivityTCCOvercurrent
FIELD NOTE · 20 MIN
TRANSFORMERS
Basics of Transformer Vector Groups
A plainspoken guide to transformer vector groups — Dyn11, YNd1, delta and wye windings, neutral availability, clock notation, 30° phase displacement, and why the vector group label matters on a one-line.
TransformersVector GroupsDyn11YNd1Phase ShiftOne-Line DiagramsProtectionGrounding
FIELD NOTE · 24 MIN
GROUNDING
Grounding & Bonding Visualized
Short technical writing, plainspoken explainers on power systems concepts. This note visualizes the difference between grounding, bonding, grounding electrode conductors, equipment grounding conductors, neutral-ground bonding, and the effective ground-fault current path.
GroundingBondingGECEGCNeutral-Ground BondFault Path
FIELD NOTE · 22 MIN
POWER QUALITY
Power Quality Waveform Lab
Reading a distorted waveform back into its harmonic spectrum.
Power QualityHarmonicsFFTTHDWaveform Analysis
FIELD NOTE · 25 MIN
NEC
NEC Load Calculation Practice
How to practice service load calculations without drowning in tables. A beginner-to-advanced guide for turning connected electrical loads into a defensible service-sizing number.
NECLoad CalculationsService SizingDemand FactorsDwelling Optional Method
FIELD NOTE · 18–25 MIN