NEC
National Electrical Code, standard for safe electrical installation.
Getting Started: Mastering the Master Electrician Exam
Free knowledge base
Master Electrician Exam (NEC) — key terms, tricks & tips
Everything from the course in one searchable place: 312 entries. Use it to review before a practice test or look up a word you forgot.
312 results · showing first 300, refine your search
Jurisdiction
Geographic area where specific laws or rules apply.
Getting Started: Mastering the Master Electrician Exam
Demand Factor
Ratio of maximum demand to total connected load.
Getting Started: Mastering the Master Electrician Exam
Load Calculation
Determining electrical power requirements for a system.
Getting Started: Mastering the Master Electrician Exam
Overcurrent Protection
Devices that protect circuits from excessive current.
Getting Started: Mastering the Master Electrician Exam
Test-Taking Strategy
Planned approach to answering exam questions efficiently.
Getting Started: Mastering the Master Electrician Exam
Process of Elimination
Method to narrow down multiple-choice options.
Getting Started: Mastering the Master Electrician Exam
Exam Structure & Strategies for Success
To remember the key steps for exam success, think 'READ': R-Review the Code, E-Execute Practice, A-Analyze Mistakes, D-Develop Strategies.
Getting Started: Mastering the Master Electrician Exam
Exam Structure & Strategies for Success
The California Master Electrician exam often includes specific questions related to Title 24, Part 6 (California Energy Code) and local amendments to the NEC. Be prepared for questions on energy efficiency, renewable energy systems, and specific California safety orders.
Getting Started: Mastering the Master Electrician Exam
Exam Structure & Strategies for Success
Not reading the entire question or all answer choices carefully.
Getting Started: Mastering the Master Electrician Exam
Exam Structure & Strategies for Success
Rushing through calculations and making simple arithmetic errors.
Getting Started: Mastering the Master Electrician Exam
Exam Structure & Strategies for Success
Failing to practice navigating the NEC book under timed conditions.
Getting Started: Mastering the Master Electrician Exam
Article
Major division of the NEC.
Getting Started: Mastering the Master Electrician Exam
Section
Specific rule or requirement within an Article.
Getting Started: Mastering the Master Electrician Exam
Index
Alphabetical listing of topics in the NEC.
Getting Started: Mastering the Master Electrician Exam
Table of Contents
Outline of NEC Chapters and Articles.
Getting Started: Mastering the Master Electrician Exam
Annex
Supplementary, non-mandatory information.
Getting Started: Mastering the Master Electrician Exam
Informative Note
Explanatory text within a Code section.
Getting Started: Mastering the Master Electrician Exam
Navigating the NEC: Tools and Techniques
To remember the NEC structure: 'Cows Always Prefer Sweet Apples, Sometimes Underneath.' (Chapters, Articles, Parts, Sections, Annexes, Subsections, Units)
Getting Started: Mastering the Master Electrician Exam
Navigating the NEC: Tools and Techniques
The California Electrical Code (CEC) is based on the NEC with specific California amendments. During the exam, be prepared to identify if a question refers to a general NEC rule or a California-specific modification, especially for topics like renewable energy or emergency systems.
Getting Started: Mastering the Master Electrician Exam
Navigating the NEC: Tools and Techniques
Relying solely on memory instead of verifying with the NEC for critical details.
Getting Started: Mastering the Master Electrician Exam
Navigating the NEC: Tools and Techniques
Not checking the Index or Table of Contents first, leading to wasted time flipping pages.
Getting Started: Mastering the Master Electrician Exam
Navigating the NEC: Tools and Techniques
Confusing mandatory Code requirements with informative notes or annexes.
Getting Started: Mastering the Master Electrician Exam
Navigating the NEC: Tools and Techniques
Misinterpreting a Code section by not reading the entire context, including exceptions.
Getting Started: Mastering the Master Electrician Exam
Voltage (V)
Electrical potential difference; 'pressure' driving current.
Module 1: General Electrical Knowledge Fundamentals
Current (I)
Rate of flow of electric charge; measured in Amperes.
Module 1: General Electrical Knowledge Fundamentals
Resistance (R)
Opposition to current flow; measured in Ohms (Ω).
Module 1: General Electrical Knowledge Fundamentals
Ohm's Law
Relates voltage, current, and resistance: V=IR.
Module 1: General Electrical Knowledge Fundamentals
Kirchhoff's Voltage Law (KVL)
Sum of voltages in a closed loop is zero.
Module 1: General Electrical Knowledge Fundamentals
Kirchhoff's Current Law (KCL)
Sum of currents entering a node equals sum leaving.
Module 1: General Electrical Knowledge Fundamentals
Power (P)
Rate at which electrical energy is converted; measured in Watts.
Module 1: General Electrical Knowledge Fundamentals
Electrical Theory: Ohm's, Kirchhoff's, Power
To remember Ohm's Law formulas, think of 'VIR' as 'Very Important Rule' and 'PIR' as 'Power Is Real'.
Module 1: General Electrical Knowledge Fundamentals
Electrical Theory: Ohm's, Kirchhoff's, Power
For the exam, be prepared to apply Ohm's Law and power formulas to calculate loads for various circuits, including motors, heating, and lighting, often requiring consideration of continuous load factors (125%) as per NEC Article 210.19(A)(1).
Module 1: General Electrical Knowledge Fundamentals
Electrical Theory: Ohm's, Kirchhoff's, Power
Confusing voltage drop with total circuit voltage in KVL calculations.
Module 1: General Electrical Knowledge Fundamentals
Electrical Theory: Ohm's, Kirchhoff's, Power
Incorrectly applying power formulas (e.g., using P=VI when only R and I are known, instead of P=I²R).
Module 1: General Electrical Knowledge Fundamentals
Electrical Theory: Ohm's, Kirchhoff's, Power
Forgetting to account for continuous loads (125% factor) when sizing conductors or overcurrent protection for certain applications.
Module 1: General Electrical Knowledge Fundamentals
Alternating Current (AC)
Current that periodically reverses direction.
Module 1: General Electrical Knowledge Fundamentals
Direct Current (DC)
Current that flows in only one direction.
Module 1: General Electrical Knowledge Fundamentals
Electromagnetic Induction
Producing voltage by changing magnetic field.
Module 1: General Electrical Knowledge Fundamentals
Transformer
Device changing AC voltage via induction.
Module 1: General Electrical Knowledge Fundamentals
Primary Winding
Input coil of a transformer.
Module 1: General Electrical Knowledge Fundamentals
Secondary Winding
Output coil of a transformer.
Module 1: General Electrical Knowledge Fundamentals
Step-Up Transformer
Increases voltage, decreases current.
Module 1: General Electrical Knowledge Fundamentals
Step-Down Transformer
Decreases voltage, increases current.
Module 1: General Electrical Knowledge Fundamentals
AC/DC Circuits, Magnetism, and Transformers
To remember transformer action: 'V' for Voltage, 'I' for Current, 'N' for Turns. Vp/Vs = Np/Ns = Is/Ip. Voltage and Turns are directly proportional; Current is inversely proportional.
Module 1: General Electrical Knowledge Fundamentals
AC/DC Circuits, Magnetism, and Transformers
The California exam frequently tests on transformer applications and calculations, particularly kVA ratings, primary/secondary currents, and voltage ratios. Pay close attention to the relationship between turns ratio and voltage/current transformation. Remember that the frequency does not change across a transformer.
Module 1: General Electrical Knowledge Fundamentals
AC/DC Circuits, Magnetism, and Transformers
Confusing the relationship between voltage and current in a transformer (e.g., assuming current also steps up when voltage steps up).
Module 1: General Electrical Knowledge Fundamentals
AC/DC Circuits, Magnetism, and Transformers
Forgetting that transformers only work with AC, not DC, because they rely on a changing magnetic field.
Module 1: General Electrical Knowledge Fundamentals
AC/DC Circuits, Magnetism, and Transformers
Ignoring the kVA rating when selecting a transformer, leading to undersized or oversized installations.
Module 1: General Electrical Knowledge Fundamentals
Motor
Converts electrical to mechanical energy.
Module 1: General Electrical Knowledge Fundamentals
Generator
Converts mechanical to electrical energy.
Module 1: General Electrical Knowledge Fundamentals
Battery
Stores chemical energy, provides DC power.
Module 1: General Electrical Knowledge Fundamentals
Contactor
Electromagnetically operated switch.
Module 1: General Electrical Knowledge Fundamentals
Motor Starter
Contactor with overload protection.
Module 1: General Electrical Knowledge Fundamentals
FLA
Full-Load Amperes; motor's current at full load.
Module 1: General Electrical Knowledge Fundamentals
Prime Mover
Source of mechanical energy for generator.
Module 1: General Electrical Knowledge Fundamentals
Motors, Generators, Batteries & Basic Controls
M-G-B-C: Motors Go By Current, Generators Get By Motion, Batteries Bring Charge, Controls Command Circuits.
Module 1: General Electrical Knowledge Fundamentals
Motors, Generators, Batteries & Basic Controls
For motor calculations, always use the full-load current (FLA) from NEC tables (e.g., 430.247, 430.248, 430.250), not the motor nameplate, unless explicitly allowed by the NEC for specific conditions. This is a common exam trick.
Module 1: General Electrical Knowledge Fundamentals
Motors, Generators, Batteries & Basic Controls
Using motor nameplate FLA instead of NEC table values for calculations.
Module 1: General Electrical Knowledge Fundamentals
Motors, Generators, Batteries & Basic Controls
Forgetting to apply the correct multipliers (e.g., 125% for conductors) mandated by the NEC.
Module 1: General Electrical Knowledge Fundamentals
Motors, Generators, Batteries & Basic Controls
Neglecting ventilation requirements for battery installations or generator rooms.
Module 1: General Electrical Knowledge Fundamentals
Grounding
Connecting electrical system/equipment to earth.
Module 1: General Electrical Knowledge Fundamentals
Bonding
Electrically connecting metallic parts for continuity.
Module 1: General Electrical Knowledge Fundamentals
OCPD
Overcurrent Protection Device (e.g., breaker, fuse).
Module 1: General Electrical Knowledge Fundamentals
Ampacity
Maximum current a conductor can carry safely.
Module 1: General Electrical Knowledge Fundamentals
Conductor Fill
Number/size of wires in conduit/raceway.
Module 1: General Electrical Knowledge Fundamentals
Box Fill
Volume occupied by conductors/devices in a box.
Module 1: General Electrical Knowledge Fundamentals
Voltage Drop
Reduction in voltage along a conductor.
Module 1: General Electrical Knowledge Fundamentals
Short Circuit
Abnormal low-resistance path for current.
Module 1: General Electrical Knowledge Fundamentals
Grounding, Bonding, OCP, Conductor/Box Fill, Voltage Drop
Remember 'G-B-O-C-V': Grounding (Earth), Bonding (Connect), Overcurrent (Protect), Conductor/Box (Fill), Voltage (Drop).
Module 1: General Electrical Knowledge Fundamentals
Grounding, Bonding, OCP, Conductor/Box Fill, Voltage Drop
The California Electrician Certification Exam heavily emphasizes NEC Articles 250 (Grounding and Bonding) and 240 (Overcurrent Protection). Be prepared to identify specific sections related to service grounding electrode systems and sizing OCPDs for various loads.
Module 1: General Electrical Knowledge Fundamentals
Grounding, Bonding, OCP, Conductor/Box Fill, Voltage Drop
Confusing grounding and bonding: Grounding connects to earth; bonding connects metallic parts together.
Module 1: General Electrical Knowledge Fundamentals
Grounding, Bonding, OCP, Conductor/Box Fill, Voltage Drop
Oversizing OCPDs without increasing conductor size: This creates a fire hazard as the wires can overheat before the breaker trips.
Module 1: General Electrical Knowledge Fundamentals
Grounding, Bonding, OCP, Conductor/Box Fill, Voltage Drop
Ignoring voltage drop: Leads to inefficient equipment, premature failure, and customer complaints.
Module 1: General Electrical Knowledge Fundamentals
Service Drop
Overhead conductors from utility to building.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Lateral
Underground conductors from utility to building.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Entrance Conductors
Conductors from service drop/lateral to service equipment.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Equipment
Main disconnect, overcurrent device, and associated components.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Disconnecting Means
Device to disconnect all ungrounded conductors.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Grounding Electrode System
Components connecting the electrical system to earth.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Entrance Conductors & Equipment
To remember the order of service components: 'Utility METERS Service DISCONNECTS and GROUNDS.' (Utility connection, Meter, Service Conductors, Disconnect, Grounding).
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Entrance Conductors & Equipment
The California Electrical Code (CEC) generally adopts NEC Article 230 without significant amendments regarding service entrance conductors and equipment. Pay close attention to exceptions for conductor sizing and the number/location of service disconnects, as these are common exam points.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Entrance Conductors & Equipment
Incorrectly sizing service conductors based on the panel rating instead of the calculated load.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Entrance Conductors & Equipment
Locating the service disconnecting means too far from the point of service entrance.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Service Entrance Conductors & Equipment
Failing to properly bond all non-current-carrying metal parts of the service equipment.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Feeder
Conductor between service equipment/source and final branch-circuit OCPD.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Branch Circuit
Conductors between the final OCPD and the outlets.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Overcurrent Protective Device (OCPD)
Device (breaker/fuse) that protects circuits from excessive current.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Continuous Load
Load where max current is expected for 3 hours or more.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Non-Continuous Load
Load where max current is expected for less than 3 hours.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Temperature Rating
Maximum operating temperature of a conductor's insulation.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Feeder & Branch Circuit Sizing and OCP
To remember the order of adjustments: 'CALM' - Continuous Load, Ambient Temperature, Length (for voltage drop, if needed), Multiple Conductors.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Feeder & Branch Circuit Sizing and OCP
The California Electrical Code (CEC) generally adopts the NEC with some amendments. For conductor sizing, always ensure you are using the correct NEC edition referenced by the CEC for your specific project year. Pay close attention to local amendments regarding specific occupancy types or environmental conditions that might impact ampacity adjustments.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Feeder & Branch Circuit Sizing and OCP
Forgetting to apply the 125% rule for continuous loads to BOTH conductor ampacity and OCPD sizing.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Feeder & Branch Circuit Sizing and OCP
Ignoring ambient temperature correction factors or adjustment factors for multiple conductors, leading to undersized conductors.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Feeder & Branch Circuit Sizing and OCP
Using the 90°C column for ampacity when the terminal connections are only rated for 75°C or 60°C without proper adjustment.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Feeder & Branch Circuit Sizing and OCP
Confusing feeder calculations with branch circuit calculations, especially regarding demand factors.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Panelboard
Enclosed assembly for OCPDs and busbars, accessible from front only.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Switchboard
Large, freestanding assembly for main power distribution.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Disconnecting Means
Device to disconnect conductors from their source of supply.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Outlet
Point on wiring system where current is taken to supply equipment.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Working Space
Clear area required around electrical equipment for safety.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
GFCI
Ground-Fault Circuit Interrupter; protects against ground faults.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Tamper-Resistant (TR)
Receptacles designed to prevent insertion of foreign objects.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Panelboards, Switchboards, Disconnects & Outlets
P-S-D-O: Panels are Smaller, Switchboards are Larger, Disconnects are for Safety, Outlets are for Power. Remember the order of power flow!
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Panelboards, Switchboards, Disconnects & Outlets
For California, pay close attention to Article 110.26 working space requirements and Article 210 for dwelling unit receptacle spacing. Also, be aware of any California amendments to NEC 230 for service disconnects, particularly regarding emergency disconnects for one- and two-family dwellings.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Panelboards, Switchboards, Disconnects & Outlets
Confusing panelboards with switchboards, especially regarding their size and application.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Panelboards, Switchboards, Disconnects & Outlets
Improperly locating service or motor disconnects, violating accessibility or 'within sight' rules.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Panelboards, Switchboards, Disconnects & Outlets
Failing to install required GFCI or tamper-resistant receptacles in dwelling units and specific locations.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
AFCI
Arc-Fault Circuit-Interrupter; device protecting against arc faults.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Habitable Room
Room used for living, sleeping, eating, or cooking.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Dedicated Circuit
Branch circuit supplying only one piece of equipment.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
VA per Sq Ft
Volt-amperes per square foot; unit for general lighting load calculation.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Wall Line
Imaginary line along the surface of a wall, including fixed panels.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Countertop Space
Continuous countertop surface, often requiring specific receptacle spacing.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Receptacles, Switches, Lighting, Appliances & HVAC
6-Foot Rule: 'Six feet to the next outlet, or you're out of luck!' (for dwelling unit wall receptacles).
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Receptacles, Switches, Lighting, Appliances & HVAC
The California Electrical Code (CEC) generally adopts NEC Article 210.52 for dwelling unit receptacle spacing. Pay close attention to specific state or local amendments that might add further requirements, especially for energy efficiency in lighting controls, but the core NEC rules are the foundation.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Receptacles, Switches, Lighting, Appliances & HVAC
Forgetting GFCI protection in required areas like garages or unfinished basements.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Receptacles, Switches, Lighting, Appliances & HVAC
Not providing a dedicated 20A circuit for laundry receptacles.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Receptacles, Switches, Lighting, Appliances & HVAC
Incorrectly calculating general lighting loads by omitting general-purpose receptacles from the VA/sq ft calculation for dwelling units.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Receptacles, Switches, Lighting, Appliances & HVAC
Placing receptacles too far apart on kitchen countertops, violating the 24-inch rule from the end or 48-inch spacing.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
FLC
Full-Load Current; current motor draws at rated load.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
BCCPD
Branch-Circuit Short-Circuit and Ground-Fault Protective Device.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
OLPD
Overload Protective Device; protects motor from overheating.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Motor Controller
Device that starts, stops, and regulates a motor.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Inverse-Time Breaker
Breaker that trips faster with higher overcurrents.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Time-Delay Fuse
Fuse designed to carry overcurrents for a short period.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Motor Circuits and Their Protection
To remember the 125% rule for conductors and overload: 'Conductors Carry 125, Overloads Overheat at 125.'
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Motor Circuits and Their Protection
For motor calculations, always refer to the specific NEC tables (like 430.247-430.250 for FLC and 430.52 for BCCPD percentages). The exam often tests your ability to navigate these tables and apply the correct multipliers.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Motor Circuits and Their Protection
Using motor nameplate FLC instead of NEC table FLC for calculations.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Motor Circuits and Their Protection
Confusing BCCPD (short-circuit/ground-fault) with OLPD (overload) protection.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Motor Circuits and Their Protection
Forgetting the 125% rule for motor conductors and overload protection.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Motor Circuits and Their Protection
Incorrectly applying the percentages from NEC Table 430.52 for BCCPD.
Module 2: Services, Feeders, and Branch Circuits Deep Dive
Unit Load
Minimum VA per square foot for general loads.
Module 3: Comprehensive Load Calculations
General Lighting Load
Calculated load for basic illumination and general-use receptacles.
Module 3: Comprehensive Load Calculations
Small-Appliance Circuit
Dedicated 20A circuits for kitchen/dining areas.
Module 3: Comprehensive Load Calculations
Fixed Appliance
Permanently connected appliances like ranges or water heaters.
Module 3: Comprehensive Load Calculations
Service Load
Total calculated load for the entire electrical service.
Module 3: Comprehensive Load Calculations
Feeder Load
Calculated load for a feeder supplying multiple branch circuits.
Module 3: Comprehensive Load Calculations
Nameplate Rating
Manufacturer's specified power consumption of equipment.
Module 3: Comprehensive Load Calculations
Residential & Commercial Load Calculations
GRASP the NEC: General, Range, Appliance, Small-appliance, Power. This helps remember the main categories for residential calculations.
Module 3: Comprehensive Load Calculations
Residential & Commercial Load Calculations
For residential calculations, remember that California amendments might affect specific demand factors or minimum circuit requirements, especially for energy-efficient appliances or renewable energy systems. Always cross-reference with Title 24.
Module 3: Comprehensive Load Calculations
Residential & Commercial Load Calculations
Forgetting to apply demand factors to general lighting and receptacle loads, leading to oversized and costly installations.
Module 3: Comprehensive Load Calculations
Residential & Commercial Load Calculations
Incorrectly applying demand factors for ranges or dryers, or using the wrong table for the specific appliance type.
Module 3: Comprehensive Load Calculations
Residential & Commercial Load Calculations
Omitting mandatory small-appliance or laundry circuits in residential calculations, underestimating the total load.
Module 3: Comprehensive Load Calculations
Diversity Factor
Ratio of sum of individual max demands to system max demand.
Module 3: Comprehensive Load Calculations
Connected Load
Sum of the nameplate ratings of all equipment.
Module 3: Comprehensive Load Calculations
Demand Load
The portion of the connected load expected to operate.
Module 3: Comprehensive Load Calculations
Industrial Establishment
Facility with manufacturing or processing operations.
Module 3: Comprehensive Load Calculations
Optional Calculation
Alternative NEC method for specific load types.
Module 3: Comprehensive Load Calculations
Industrial & Optional Calculations; Demand Factors
FARM-SCHOOL-IND: Remember the special optional calculation articles for Farms (220.89), Schools (220.86), and Industrial (220.82) facilities.
Module 3: Comprehensive Load Calculations
Industrial & Optional Calculations; Demand Factors
For California, pay close attention to any local amendments to NEC Article 220.82, 220.86, and 220.89 that might modify demand factors or calculation methods for industrial, school, or farm services. The exam often tests your ability to apply these specific articles.
Module 3: Comprehensive Load Calculations
Industrial & Optional Calculations; Demand Factors
Confusing demand factors with diversity factors; they are not interchangeable.
Module 3: Comprehensive Load Calculations
Industrial & Optional Calculations; Demand Factors
Applying residential or commercial demand factors to industrial or farm loads.
Module 3: Comprehensive Load Calculations
Industrial & Optional Calculations; Demand Factors
Forgetting to check the specific NEC article (e.g., 220.82) for the correct demand factors.
Module 3: Comprehensive Load Calculations
Industrial & Optional Calculations; Demand Factors
Not accounting for continuous loads (125%) even after applying demand factors.
Module 3: Comprehensive Load Calculations
Full-Load Current (FLC)
Current a motor draws at its rated horsepower and voltage.
Module 3: Comprehensive Load Calculations
Multi-Family Dwelling
Building containing three or more dwelling units.
Module 3: Comprehensive Load Calculations
Farm Dwelling
A single-family dwelling located on a farm.
Module 3: Comprehensive Load Calculations
Multi-Family, Farm, Motor & HVAC Load Calculations
MFH-M: Multi-Family Homes, Motors, and HVAC. Remember the 'M' for Motors and 'H' for HVAC, and the 'MF' for Multi-Family, to recall these specialized load types.
Module 3: Comprehensive Load Calculations
Multi-Family, Farm, Motor & HVAC Load Calculations
The California Electrical Code (CEC) generally adopts NEC Article 220 without significant amendments for these calculations. However, always verify local amendments for specific jurisdictions, especially regarding energy efficiency requirements for HVAC systems that might indirectly affect load calculations.
Module 3: Comprehensive Load Calculations
Multi-Family, Farm, Motor & HVAC Load Calculations
Forgetting to apply the 125% rule to the largest motor in a multi-motor circuit.
Module 3: Comprehensive Load Calculations
Multi-Family, Farm, Motor & HVAC Load Calculations
Applying demand factors for single-family dwellings to multi-family services without using the correct NEC tables.
Module 3: Comprehensive Load Calculations
Multi-Family, Farm, Motor & HVAC Load Calculations
Including both heating and cooling loads at full value simultaneously in HVAC calculations when only one operates at a time.
Module 3: Comprehensive Load Calculations
Occupancy Type
Classification of a building or space affecting NEC load calculation rules.
Module 3: Comprehensive Load Calculations
Gross Floor Area
Total area of all floors for load calculations, excluding specific unconditioned spaces.
Module 3: Comprehensive Load Calculations
NEC Table 220.12
Table specifying general lighting loads by occupancy in VA/sq ft.
Module 3: Comprehensive Load Calculations
Service Sizing
Determining the capacity of the main electrical service for a building.
Module 3: Comprehensive Load Calculations
Lighting Load Calculations & Diversity Factors
To remember the common VA/sq ft for Dwellings: 'Dwellings are a '3' ring circus!' (3 VA/sq ft).
Module 3: Comprehensive Load Calculations
Lighting Load Calculations & Diversity Factors
The California Electrical Code (CEC) adopts NEC Article 220 without significant amendments regarding general lighting load calculations. Focus on memorizing key VA/sq ft values from Table 220.12 for common occupancies like dwelling units (3 VA/sq ft) and offices (3.5 VA/sq ft).
Module 3: Comprehensive Load Calculations
Lighting Load Calculations & Diversity Factors
Using the wrong VA/sq ft value for the occupancy type from NEC Table 220.12.
Module 3: Comprehensive Load Calculations
Lighting Load Calculations & Diversity Factors
Forgetting to apply the 125% rule for continuous lighting loads when sizing conductors/OCPDs.
Module 3: Comprehensive Load Calculations
Lighting Load Calculations & Diversity Factors
Confusing diversity factor with demand factor; they are distinct concepts.
Module 3: Comprehensive Load Calculations
Hazardous Location
Area where flammable substances are present, requiring special electrical installations.
Module 4: Special Occupancies, Equipment, and Conditions
Class I
Location with flammable gases or vapors.
Module 4: Special Occupancies, Equipment, and Conditions
Class II
Location with combustible dusts.
Module 4: Special Occupancies, Equipment, and Conditions
Class III
Location with ignitable fibers or flyings.
Module 4: Special Occupancies, Equipment, and Conditions
Division 1
Hazardous material present under normal operating conditions.
Module 4: Special Occupancies, Equipment, and Conditions
Division 2
Hazardous material present only under abnormal conditions.
Module 4: Special Occupancies, Equipment, and Conditions
Explosion-Proof
Enclosure designed to contain an internal explosion without igniting external atmosphere.
Module 4: Special Occupancies, Equipment, and Conditions
Essential Electrical System
System providing power to critical loads in healthcare facilities during outages.
Module 4: Special Occupancies, Equipment, and Conditions
Hazardous Locations & Healthcare Facilities
For Hazardous Locations: 'Classes Divide Groups of Temps' helps remember Class, Division, Group, and Temperature Code.
Module 4: Special Occupancies, Equipment, and Conditions
Hazardous Locations & Healthcare Facilities
The California Electrical Code (CEC) largely adopts the NEC. For hazardous locations, pay close attention to the specific Class, Division, and Group definitions in Articles 500-506. For healthcare facilities, memorize the three branches of the essential electrical system (Life Safety, Critical, Equipment) and their typical loads, as this is a frequent exam topic.
Module 4: Special Occupancies, Equipment, and Conditions
Hazardous Locations & Healthcare Facilities
Misclassifying a hazardous location, leading to inadequate or over-engineered installations.
Module 4: Special Occupancies, Equipment, and Conditions
Hazardous Locations & Healthcare Facilities
Failing to install required sealing fittings in conduits entering/leaving hazardous areas.
Module 4: Special Occupancies, Equipment, and Conditions
Hazardous Locations & Healthcare Facilities
Not understanding the specific loads served by each branch of the essential electrical system in healthcare facilities.
Module 4: Special Occupancies, Equipment, and Conditions
Temporary Wiring
Wiring installed for a limited time for specific purposes.
Module 4: Special Occupancies, Equipment, and Conditions
Emergency System
Legally required power for life safety during outages.
Module 4: Special Occupancies, Equipment, and Conditions
Legally Required Standby System
Mandated power for critical operations, not just life safety.
Module 4: Special Occupancies, Equipment, and Conditions
Optional Standby System
Voluntary backup power for convenience or economic reasons.
Module 4: Special Occupancies, Equipment, and Conditions
Automatic Transfer Switch (ATS)
Device that switches power sources automatically.
Module 4: Special Occupancies, Equipment, and Conditions
GFCI Protection
Ground-Fault Circuit Interrupter for personnel safety.
Module 4: Special Occupancies, Equipment, and Conditions
Article 590
NEC article for temporary wiring installations.
Module 4: Special Occupancies, Equipment, and Conditions
Article 700
NEC article for emergency systems.
Module 4: Special Occupancies, Equipment, and Conditions
Temporary Installations & Emergency Systems
Remember 'TEMP': T-Temporary, E-Emergency, M-Mandatory (Legally Required), P-Personal Choice (Optional). This helps categorize the different types of backup/temporary power.
Module 4: Special Occupancies, Equipment, and Conditions
Temporary Installations & Emergency Systems
For temporary wiring, remember that GFCI protection for personnel is required for all 125-volt, single-phase, 15-, 20-, and 30-ampere receptacles used for temporary power during construction, remodeling, or demolition. This is a frequently tested detail.
Module 4: Special Occupancies, Equipment, and Conditions
Temporary Installations & Emergency Systems
Using temporary wiring as a permanent solution or leaving it installed beyond its permitted duration.
Module 4: Special Occupancies, Equipment, and Conditions
Temporary Installations & Emergency Systems
Failing to provide proper GFCI protection for personnel on construction sites.
Module 4: Special Occupancies, Equipment, and Conditions
Temporary Installations & Emergency Systems
Intermixing emergency system wiring with normal system wiring, compromising reliability.
Module 4: Special Occupancies, Equipment, and Conditions
Temporary Installations & Emergency Systems
Not performing required periodic testing of emergency and standby systems.
Module 4: Special Occupancies, Equipment, and Conditions
Photovoltaic (PV)
System converting light into electricity using semiconductors.
Module 4: Special Occupancies, Equipment, and Conditions
Rapid Shutdown
NEC requirement to quickly de-energize PV systems for safety.
Module 4: Special Occupancies, Equipment, and Conditions
EVSE
Electric Vehicle Supply Equipment, for charging electric vehicles.
Module 4: Special Occupancies, Equipment, and Conditions
Energy Storage System
System storing electrical energy (e.g., batteries, capacitors).
Module 4: Special Occupancies, Equipment, and Conditions
Thermal Runaway
Uncontrolled self-heating in batteries, leading to failure.
Module 4: Special Occupancies, Equipment, and Conditions
Fuel Cell System
Generates electricity through chemical reaction, not combustion.
Module 4: Special Occupancies, Equipment, and Conditions
Solar PV, EV Charging, Energy Storage & Other Systems
PV-EV-ESS: Protect Every Volt, Every System, Safely. Remember the articles: 690 (PV), 625 (EV), 706 (ESS).
Module 4: Special Occupancies, Equipment, and Conditions
Solar PV, EV Charging, Energy Storage & Other Systems
The California Electrical Code (CEC) often has amendments to NEC Articles 690, 625, and 706. Pay close attention to specific California rapid shutdown requirements for PV, and any local utility interconnection rules for EV charging and ESS.
Module 4: Special Occupancies, Equipment, and Conditions
Solar PV, EV Charging, Energy Storage & Other Systems
Under-sizing conductors for EVSE due to neglecting the 125% continuous load factor.
Module 4: Special Occupancies, Equipment, and Conditions
Solar PV, EV Charging, Energy Storage & Other Systems
Improperly labeling PV system components, especially DC conductors and disconnects.
Module 4: Special Occupancies, Equipment, and Conditions
Solar PV, EV Charging, Energy Storage & Other Systems
Failing to provide adequate ventilation for battery-based energy storage systems.
Module 4: Special Occupancies, Equipment, and Conditions
Shore Power
Electrical power supplied from land to a boat.
Module 4: Special Occupancies, Equipment, and Conditions
Equipotential Plane
Area where all conductive surfaces are bonded together.
Module 4: Special Occupancies, Equipment, and Conditions
Corrosive Atmosphere
Environment that degrades materials, common in agriculture.
Module 4: Special Occupancies, Equipment, and Conditions
Locking-Type Receptacle
Receptacle designed to prevent accidental disconnection.
Module 4: Special Occupancies, Equipment, and Conditions
Isolated Transformer
Transformer with no direct electrical connection between primary and secondary.
Module 4: Special Occupancies, Equipment, and Conditions
Stray Voltage
Small voltage differences that can affect livestock.
Module 4: Special Occupancies, Equipment, and Conditions
Marinas, Pools, Theaters & Agricultural Buildings
MAPS: Marinas, Agricultural, Pools, Stages – Remember these four special occupancies for unique NEC rules!
Module 4: Special Occupancies, Equipment, and Conditions
Marinas, Pools, Theaters & Agricultural Buildings
The California Electrical Code (CEC) often has amendments to the NEC, especially concerning public safety and environmental factors. For pools, be aware of any California-specific requirements for bonding grid dimensions or additional GFCI requirements. For agricultural buildings, California might have stricter rules on wiring methods or corrosion protection due to specific regional conditions.
Module 4: Special Occupancies, Equipment, and Conditions
Marinas, Pools, Theaters & Agricultural Buildings
Failing to provide GFCI protection for all required receptacles in specific occupancies.
Module 4: Special Occupancies, Equipment, and Conditions
Marinas, Pools, Theaters & Agricultural Buildings
Neglecting proper bonding of all metal parts around pools and spas.
Module 4: Special Occupancies, Equipment, and Conditions
Marinas, Pools, Theaters & Agricultural Buildings
Using standard wiring methods in corrosive or damp agricultural environments.
Module 4: Special Occupancies, Equipment, and Conditions
Marinas, Pools, Theaters & Agricultural Buildings
Underestimating the importance of emergency lighting in assembly areas.
Module 4: Special Occupancies, Equipment, and Conditions
Industrial Machinery
Power-driven machines for manufacturing.
Module 4: Special Occupancies, Equipment, and Conditions
Elevator Disconnect
Switch to de-energize elevator power, within sight.
Module 4: Special Occupancies, Equipment, and Conditions
Information Technology Equipment
Computers, servers, and associated hardware.
Module 4: Special Occupancies, Equipment, and Conditions
Emergency Power-Off (EPO)
Switch to quickly cut power to IT equipment.
Module 4: Special Occupancies, Equipment, and Conditions
Raised Floor
Elevated floor in IT rooms for cables/cooling.
Module 4: Special Occupancies, Equipment, and Conditions
Article 670
NEC section for industrial machinery.
Module 4: Special Occupancies, Equipment, and Conditions
Article 620
NEC section for elevators and escalators.
Module 4: Special Occupancies, Equipment, and Conditions
Industrial Machinery, Elevators & Data Processing
I.T. E.P.O. = 'IT's Emergency Power Off!' - Remember the critical EPO switch for data centers.
Module 4: Special Occupancies, Equipment, and Conditions
Industrial Machinery, Elevators & Data Processing
For the California Master Electrician exam, pay close attention to local amendments to NEC Articles 620, 645, and 670, especially regarding emergency systems, fire safety, and accessibility requirements. Some jurisdictions may have stricter rules for data centers or specific industrial installations.
Module 4: Special Occupancies, Equipment, and Conditions
Industrial Machinery, Elevators & Data Processing
Under-sizing conductors for industrial machinery by only using the nameplate FLA, ignoring the 125% rule for heating loads.
Module 4: Special Occupancies, Equipment, and Conditions
Industrial Machinery, Elevators & Data Processing
Placing elevator disconnects outside the 'within sight' rule, creating a safety hazard and code violation.
Module 4: Special Occupancies, Equipment, and Conditions
Industrial Machinery, Elevators & Data Processing
Not installing or improperly labeling the Emergency Power-Off (EPO) switch in an IT equipment room, which is a critical fire safety device.
Module 4: Special Occupancies, Equipment, and Conditions
Grounding Electrode Conductor
Connects service equipment to the grounding electrode system.
Module 5: Grounding and Bonding Essentials
Effective Grounding
Low impedance path to earth for fault current.
Module 5: Grounding and Bonding Essentials
Ground Rod
Metal rod driven into the earth for grounding.
Module 5: Grounding and Bonding Essentials
Ufer Ground
Concrete-encased electrode (reinforcing bar).
Module 5: Grounding and Bonding Essentials
Fault Current
Unintended current flow through an abnormal path.
Module 5: Grounding and Bonding Essentials
Purpose of Grounding & Bonding; Electrode Systems
Think 'G-E-C': Grounding, Electrode, Conductor – it's the direct path from your panel to the Earth's core, keeping things safe!
Module 5: Grounding and Bonding Essentials
Purpose of Grounding & Bonding; Electrode Systems
Memorize NEC 250.50, which mandates that all accessible grounding electrodes at a building or structure must be bonded together to form a single grounding electrode system. This is a common point of confusion and examination.
Module 5: Grounding and Bonding Essentials
Purpose of Grounding & Bonding; Electrode Systems
Failing to bond all available grounding electrodes together into a single system.
Module 5: Grounding and Bonding Essentials
Purpose of Grounding & Bonding; Electrode Systems
Using an undersized grounding electrode conductor (GEC).
Module 5: Grounding and Bonding Essentials
Purpose of Grounding & Bonding; Electrode Systems
Confusing the purpose of grounding (connection to earth) with bonding (connection of metal parts).
Module 5: Grounding and Bonding Essentials
Grounding Electrode Conductor (GEC)
Connects service equipment to grounding electrode system.
Module 5: Grounding and Bonding Essentials
Equipment Grounding Conductor (EGC)
Provides path for fault current back to the source.
Module 5: Grounding and Bonding Essentials
Overcurrent Protective Device
Device (breaker/fuse) that opens a circuit under fault conditions.
Module 5: Grounding and Bonding Essentials
Continuity
Uninterrupted electrical path without splices or breaks.
Module 5: Grounding and Bonding Essentials
Grounding Electrode & Equipment Grounding Conductors
GEC goes to Earth, EGC goes to Equipment. Earth is big (250.66), Equipment is smaller (250.122).
Module 5: Grounding and Bonding Essentials
Grounding Electrode & Equipment Grounding Conductors
The California Electrical Code (CEC) adopts NEC Article 250 without significant amendments regarding GEC and EGC sizing and installation. Focus on memorizing NEC Tables 250.66 and 250.122.
Module 5: Grounding and Bonding Essentials
Grounding Electrode & Equipment Grounding Conductors
Using an EGC as a GEC, or vice versa, due to misunderstanding their distinct functions.
Module 5: Grounding and Bonding Essentials
Grounding Electrode & Equipment Grounding Conductors
Improperly sizing GECs or EGCs, leading to inadequate fault clearing or surge protection.
Module 5: Grounding and Bonding Essentials
Grounding Electrode & Equipment Grounding Conductors
Making splices in the GEC where not permitted by NEC 250.64(C).
Module 5: Grounding and Bonding Essentials
Grounding Electrode & Equipment Grounding Conductors
Not protecting GECs or EGCs from physical damage, especially when exposed.
Module 5: Grounding and Bonding Essentials
Bonding Jumper
Conductor ensuring electrical continuity.
Module 5: Grounding and Bonding Essentials
Main Bonding Jumper (MBJ)
Connects service neutral to EGC and enclosure.
Module 5: Grounding and Bonding Essentials
System Bonding Jumper (SBJ)
Connects derived neutral to EGC and enclosure.
Module 5: Grounding and Bonding Essentials
Separately Derived System
Electrical source with no direct connection to another system.
Module 5: Grounding and Bonding Essentials
Ground-Fault Current Path
Path for fault current to return to source.
Module 5: Grounding and Bonding Essentials
Bonding Jumpers & Separately Derived Systems
Think 'MBJ for Main, SBJ for Separate.' It helps you remember which bonding jumper applies to the service versus a derived system.
Module 5: Grounding and Bonding Essentials
Bonding Jumpers & Separately Derived Systems
For the exam, pay close attention to NEC Article 250.30 regarding separately derived systems. Keywords like 'transformer secondary' or 'generator output' should trigger your knowledge of system bonding jumpers and dedicated grounding electrodes. Remember the specific sizing tables for MBJs and SBJs.
Module 5: Grounding and Bonding Essentials
Bonding Jumpers & Separately Derived Systems
Forgetting to install a System Bonding Jumper (SBJ) on a separately derived system.
Module 5: Grounding and Bonding Essentials
Bonding Jumpers & Separately Derived Systems
Incorrectly sizing bonding jumpers, leading to inadequate fault current paths.
Module 5: Grounding and Bonding Essentials
Bonding Jumpers & Separately Derived Systems
Confusing the requirements for a Main Bonding Jumper with a System Bonding Jumper.
Module 5: Grounding and Bonding Essentials
Main Bonding Jumper
Connects the grounded service conductor to the equipment grounding conductor.
Module 5: Grounding and Bonding Essentials
Effective Ground-Fault Current Path
An intentionally constructed, low-impedance path to clear ground faults.
Module 5: Grounding and Bonding Essentials
Grounding of Services, Equipment, Enclosures & Raceways
Grounded Service Equipment: 'Grounded Service Needs Main Bonding and Electrode Connection.' (Grounded Service, Main Bonding Jumper, Grounding Electrode Conductor, Grounding Electrode)
Module 5: Grounding and Bonding Essentials
Grounding of Services, Equipment, Enclosures & Raceways
The California Electrical Code (CEC) generally adopts NEC Article 250 without significant amendments for grounding services, equipment, enclosures, and raceways. Pay close attention to NEC Table 250.66 for service grounding electrode conductor sizing and NEC Table 250.122 for equipment grounding conductor sizing. These tables are frequently referenced on the exam.
Module 5: Grounding and Bonding Essentials
Grounding of Services, Equipment, Enclosures & Raceways
Failing to install a main bonding jumper at the service disconnecting means, creating an unsafe floating neutral.
Module 5: Grounding and Bonding Essentials
Grounding of Services, Equipment, Enclosures & Raceways
Incorrectly sizing the grounding electrode conductor or equipment grounding conductors, leading to an ineffective fault current path.
Module 5: Grounding and Bonding Essentials
Grounding of Services, Equipment, Enclosures & Raceways
Assuming all metal raceways automatically qualify as equipment grounding conductors without checking continuity or specific NEC allowances.
Module 5: Grounding and Bonding Essentials
Grounding of Services, Equipment, Enclosures & Raceways
Confusing grounding (connection to earth) with bonding (connection between metallic parts).
Module 5: Grounding and Bonding Essentials
Overcurrent
Any current exceeding the rated current of equipment or conductors.
Module 6: Overcurrent Protection Systems
Overload
Operation in excess of normal full-load current.
Module 6: Overcurrent Protection Systems
Ground Fault
An unintentional electrical contact between an ungrounded conductor and ground.
Module 6: Overcurrent Protection Systems
Interrupting Rating (IR)
Maximum fault current an OCPD can safely interrupt.
Module 6: Overcurrent Protection Systems
Ampere Rating
Maximum continuous current an OCPD is designed to carry.
Module 6: Overcurrent Protection Systems
Voltage Rating
Maximum voltage an OCPD can safely interrupt.
Module 6: Overcurrent Protection Systems
Fuses, Circuit Breakers & Device Ratings
Fuses are 'Fired' once, Circuit Breakers are 'Clickable' again. Remember F-F, C-C!
Module 6: Overcurrent Protection Systems
Fuses, Circuit Breakers & Device Ratings
The California Master Electrician exam frequently tests on the correct application of NEC 240.4 (Protection of Conductors) and 240.6 (Standard Ampere Ratings). Memorize the standard ampere ratings and understand the 'next higher standard OCPD' rule for non-motor loads.
Module 6: Overcurrent Protection Systems
Fuses, Circuit Breakers & Device Ratings
Replacing a blown fuse with one of a higher ampere rating, which can lead to conductor damage or fire.
Module 6: Overcurrent Protection Systems
Fuses, Circuit Breakers & Device Ratings
Ignoring the interrupting rating (IR) of an OCPD, potentially causing device explosion during a high-fault condition.
Module 6: Overcurrent Protection Systems
Fuses, Circuit Breakers & Device Ratings
Not accounting for continuous loads (125% rule) when sizing overcurrent protection, leading to nuisance tripping or undersized protection.
Module 6: Overcurrent Protection Systems
Interrupting Rating (AIC)
Maximum fault current an OCPD can safely interrupt.
Module 6: Overcurrent Protection Systems
Available Fault Current
Maximum current that could flow during a short circuit.
Module 6: Overcurrent Protection Systems
Selective Coordination
Only nearest OCPD to a fault trips, minimizing outages.
Module 6: Overcurrent Protection Systems
Time-Current Curves
Graphs showing OCPD trip times at various current levels.
Module 6: Overcurrent Protection Systems
Series Rating
Using lower-rated OCPDs protected by an upstream higher-rated one.
Module 6: Overcurrent Protection Systems
Interrupting Ratings & Selective Coordination
AIC: Always Interrupt Correctly! Remember, if the fault current is too high, your device goes BOOM!
Module 6: Overcurrent Protection Systems
Interrupting Ratings & Selective Coordination
The California Electrical Code (CEC) adopts NEC Article 110.9 directly, emphasizing the critical importance of selecting overcurrent protective devices with adequate interrupting ratings based on the available fault current. Pay close attention to available fault current calculations and the specific requirements for emergency and legally required standby systems.
Module 6: Overcurrent Protection Systems
Interrupting Ratings & Selective Coordination
Installing an OCPD with an interrupting rating lower than the available fault current, leading to device destruction.
Module 6: Overcurrent Protection Systems
Interrupting Ratings & Selective Coordination
Failing to perform a selective coordination study for critical systems, resulting in widespread outages during a fault.
Module 6: Overcurrent Protection Systems
Interrupting Ratings & Selective Coordination
Confusing continuous current rating with interrupting rating; they are distinct and equally important.
Module 6: Overcurrent Protection Systems
Ground-Fault
Unintended current path to ground, often through a person.
Module 6: Overcurrent Protection Systems
Arc-Fault
Dangerous electrical discharge causing intense heat and fire risk.
Module 6: Overcurrent Protection Systems
Combination AFCI
AFCI protecting against both parallel and series arc faults.
Module 6: Overcurrent Protection Systems
5 Milliamperes
Typical trip threshold for a GFCI device.
Module 6: Overcurrent Protection Systems
NEC Article 210.8
Code section detailing GFCI requirements.
Module 6: Overcurrent Protection Systems
NEC Article 210.12
Code section detailing AFCI requirements.
Module 6: Overcurrent Protection Systems