How to use this glossary without turning it into a rabbit hole
The point of this glossary is speed. If a calculator, code article, or field conversation throws an acronym at you, search the term here, get the plain-English definition, then move back into the calculation or code reference that matters.
It is especially useful for the terms the audits kept flagging as confusion points: FLC versus FLA, AIC, GEC versus EGC, continuous load, available fault current, and the difference between Canadian Electrical Code and California code references.
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Search acronyms, code language, and common field terms. The glossary currently includes 127 definitions.
11 terms
AFCI
Arc-Fault Circuit Interrupter. A protective device that trips when it detects dangerous arcing signatures that can start electrical fires.
Related resourceAIC
Ampere Interrupting Capacity. The maximum fault current a breaker or fuse can safely interrupt at its rated voltage.
Related resourceAlternating Current
Current that periodically reverses direction. Standard utility power in North America is alternating current, or AC.
Aluminum Conductor
A lighter, lower-cost conductor material than copper that typically requires larger wire sizes and listed terminations.
Ampacity
The maximum current a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
Related resourceAmpere
The unit used to measure electric current. Electricians usually shorten it to amp.
Apparent Power
Total power in an AC circuit measured in volt-amperes. Apparent power combines real power and reactive power.
Arc Flash
An explosive electrical event where current jumps through the air, releasing intense heat, light, pressure, and molten metal.
Related resourceArc Rating
The amount of incident energy arc-rated PPE can withstand before the wearer risks a second-degree burn, usually stated in cal/cm2.
Available Fault Current
The maximum short-circuit current available at a specific point in an electrical system.
Related resourceAWG
American Wire Gauge. The standard sizing system for conductors smaller than 4/0 in North American wiring.
5 terms
Bonding
Intentionally connecting conductive parts together to keep them at the same electrical potential and create an effective fault-current path.
Bonding Jumper
A conductor used to ensure electrical continuity between metallic parts that must be bonded together.
Branch Circuit
The conductors between the final overcurrent device protecting the circuit and the outlets or equipment served by that circuit.
Breaker
A resettable overcurrent protective device that opens a circuit during overloads or short circuits.
Related resourceBusbar
A rigid conductor inside equipment such as panelboards, switchboards, or switchgear used to distribute current.
13 terms
Cable Tray
A structural system used to support insulated conductors and cables in commercial and industrial installations.
Related resourceCanadian Electrical Code
The national electrical installation code used in Canada, commonly shortened to CEC. On SparkShift, CEC means Canadian Electrical Code, not California electrical code.
Related resourceCircular Mil
A unit of conductor area used in wire sizing and voltage drop formulas. Circular mils are especially common in NEC Chapter 9 tables.
Related resourceCode Cycle
The edition year of the adopted electrical code, such as NEC 2023, NEC 2026, or CEC 2024.
Conductor
A material that allows electric current to flow. In building wiring, the conductor is usually copper or aluminum.
Conductor Ampacity
The allowable current for a conductor after considering insulation, temperature rating, ambient temperature, and adjustment factors.
Conduit Fill
The percentage of a raceway's internal area occupied by conductors.
Related resourceContinuous Load
A load where the maximum current is expected to continue for three hours or more. Continuous loads are generally sized at 125 percent.
Related resourceControl Circuit
A circuit used to carry signals or operate control devices rather than deliver power directly to the load.
Copper Conductor
The most common conductor material in building wiring due to its high conductivity and strong termination performance.
Current
The flow of electric charge through a conductor, measured in amperes.
Current-Carrying Conductor
A conductor that normally carries load current. Equipment grounding conductors do not count as current-carrying conductors for derating.
Current Transformer
A transformer that reduces current to a measurable value for metering or protective relaying.
7 terms
Demand Factor
A code-permitted percentage reduction applied to a connected load because not all loads operate simultaneously.
Related resourceDerating
Reducing a conductor's allowable ampacity because of ambient temperature, conductor bundling, or other installation conditions.
Related resourceDisconnect
A device used to isolate equipment from its power source so it can be serviced safely.
Diversity Factor
A planning concept showing that multiple loads are unlikely to peak at the same time. In code calculations, this idea appears through demand factors.
Dry Location
A location not normally subject to dampness or saturation with water.
Dual-Function Breaker
A breaker that provides both AFCI and GFCI protection in the same device.
Dwelling Unit
A single unit that provides complete, independent living facilities including cooking, sleeping, and sanitation.
6 terms
Effective Ground-Fault Current Path
An intentionally low-impedance conductive path that carries ground-fault current back to the source to help an overcurrent device clear the fault.
EGC
Equipment Grounding Conductor. The fault-clearing conductor run with the circuit conductors and sized from NEC Table 250.122.
Related resourceElectrical Metallic Tubing
A thin-wall metal raceway commonly abbreviated as EMT.
Related resourceEmergency System
A legally required standby or emergency distribution system intended to keep life-safety loads operating when normal power fails.
Equipment Bonding Jumper
A conductor used to bond metal parts of equipment together or to the supply-side bonding point.
Equipment Grounding Conductor
The conductive path that connects non-current-carrying metal parts to ground and back to the source to clear faults.
Related resource4 terms
Feeder
Conductors between service equipment or another power source and the final branch-circuit overcurrent device.
FLA
Full-Load Amperes from the motor nameplate. FLA is used for overload protection, not most conductor or OCPD sizing.
Related resourceFLC
Full-Load Current from the applicable code motor table. FLC is used for motor conductor sizing and branch-circuit protection.
Related resourceFault Current
Current that flows during a short circuit or ground fault rather than normal operation.
6 terms
GEC
Grounding Electrode Conductor. The conductor that connects the grounded service conductor or equipment to the grounding electrode system.
Related resourceGFCI
Ground-Fault Circuit Interrupter. A device that trips when it senses a small current imbalance that can indicate shock hazard.
Ground-Fault
An unintentional connection between an energized conductor and ground or grounded metal parts.
Grounded Conductor
A system or circuit conductor that is intentionally grounded. In many premises wiring systems, this is the neutral.
Grounding Electrode
A conductive object, such as a ground rod or concrete-encased electrode, used to connect the electrical system to earth.
Grounding Electrode Conductor
The conductor that ties the service or separately derived system to the grounding electrode system.
Related resource3 terms
Harmonic
A frequency component of an AC waveform that is an integer multiple of the fundamental frequency, often caused by nonlinear loads.
Horsepower
A unit of power commonly used for motors. One horsepower equals 746 watts.
Related resourceHub
A listed fitting that connects a raceway to an enclosure and often provides a raintight entry.
6 terms
IMC
Intermediate Metal Conduit. A metal raceway heavier than EMT and lighter than rigid metal conduit.
Related resourceImpedance
The total opposition to AC current flow, combining resistance and reactance.
Related resourceIncident Energy
The thermal energy from an arc flash at a specified working distance, commonly stated in cal/cm2.
Related resourceInterrupting Rating
The highest fault current a device can safely interrupt at rated voltage.
Related resourceInverse-Time Breaker
A breaker that trips faster as overcurrent magnitude increases while still allowing temporary inrush current.
Isolated Ground
A specialized grounding arrangement used for certain sensitive equipment. It is not the same thing as a regular equipment grounding conductor.
2 terms
Jam Ratio
A conduit fill concern where three conductors can wedge in a bend if conduit diameter and wire diameter fall into a specific ratio range.
Related resourceJunction Box
An enclosure used for splices, terminations, or conductor access points.
3 terms
kAIC
Kiloampere Interrupting Capacity. AIC stated in thousands of amperes, such as 10 kAIC or 22 kAIC.
Kilovolt-Ampere
A unit of apparent power commonly used to rate transformers.
Related resourceKilowatt
A unit of real power equal to 1,000 watts.
7 terms
Lagging Power Factor
A power-factor condition typical of inductive loads such as motors, where current lags voltage.
Learning Mode
SparkShift's expanded explanation mode that shows the reasoning behind calculations and code references.
Line-to-Line Voltage
Voltage measured between two ungrounded conductors in a multi-phase system.
Line-to-Neutral Voltage
Voltage measured between an ungrounded conductor and the grounded conductor in a system with a neutral.
Listed
Equipment included in a published list from a qualified testing organization and evaluated for a specific purpose.
Load Calculation
A code-based method used to determine the required service, feeder, or branch-circuit capacity for a set of loads.
Related resourceLockout Tagout
A procedure used to isolate hazardous energy sources and prevent unexpected re-energization during work.
6 terms
Main Bonding Jumper
The connection between the grounded conductor and the equipment grounding/bonding system at service equipment.
MC Cable
Metal-clad cable. A factory assembly of insulated conductors in an interlocked or smooth metal sheath.
MCA
Minimum Circuit Ampacity. A value often shown on HVAC and equipment nameplates to help size conductors.
Metallic Raceway
A metal pathway such as EMT, IMC, or RMC used to contain and protect conductors.
Motor Contribution
Additional fault current contributed by running motors during a short circuit. Simplified short-circuit tools may not include it.
Multiwire Branch Circuit
A branch circuit with two or more ungrounded conductors sharing a grounded conductor.
4 terms
NEMA
National Electrical Manufacturers Association. NEMA publishes enclosure ratings, device configurations, motor starter sizes, and other standards.
NM-B
Nonmetallic-sheathed cable commonly used in residential wiring. It is often called Romex in the field.
Related resourceNeutral
A common field term for the grounded conductor in an AC system.
Noncontinuous Load
A load not expected to run at maximum current for three hours or more.
6 terms
OCPD
Overcurrent Protective Device. A general term that includes breakers and fuses.
Related resourceOhm
The unit of electrical resistance.
Ohm's Law
The basic relationship between voltage, current, and resistance: V = I x R.
Related resourceOptional Method
A simplified dwelling-load calculation method allowed for qualifying installations under NEC 220.82 / 120.82.
Related resourceOvercurrent
Any current above the rated current of equipment or conductor ampacity, including overloads and short circuits.
Overload
Operation above normal full-load current that persists long enough to cause overheating if not cleared.
6 terms
Panelboard
A cabinet with buses and overcurrent devices that distributes power to branch circuits.
Parallel Conductors
Multiple conductors per phase installed in parallel to share current. NEC rules require matching size, material, length, and termination details.
Phase
One alternating-current waveform in relation to another. Common systems are single-phase and three-phase.
Point-to-Point Method
A simplified fault-current calculation method that starts at the source and subtracts current through conductor impedance segment by segment.
Related resourcePower Factor
The ratio of real power to apparent power in an AC circuit.
Related resourcePPE
Personal Protective Equipment. In electrical work this often includes gloves, face shields, arc-rated clothing, and eye protection.
6 terms
Raceway
An enclosed channel such as conduit, tubing, or wireway designed to hold conductors.
Reactive Power
Power that oscillates between the source and reactive components such as motors or capacitors, measured in vars.
Receptacle
A contact device installed at an outlet for the connection of an attachment plug.
Resistance
Opposition to current flow that turns electrical energy into heat.
Related resourceRMC
Rigid Metal Conduit. A heavy-wall threaded metal raceway used where strong physical protection is needed.
Related resourceRomex
A common trade name often used to refer to NM-B nonmetallic-sheathed cable.
12 terms
SCAR
Short-Circuit Current Rating. The maximum short-circuit current a component or assembly can safely withstand under specified conditions.
Service
The conductors and equipment that deliver electric power from the utility or other source to the premises wiring system.
Service Conductor
A conductor from the service point to the service disconnecting means.
Service Disconnect
The device or devices used to disconnect all power from the service conductors to the premises wiring system.
Service Drop
The overhead conductors between the utility distribution system and the service point.
Service Entrance
A common field term for the portion of the installation where service conductors enter the building and terminate at service equipment.
Service Factor
A motor multiplier indicating how much load a motor can carry above its rated horsepower under specified conditions.
Related resourceShort Circuit
An abnormal connection with very low impedance that allows a high current to flow outside the intended load path.
Related resourceSingle-Phase
An AC system with one voltage waveform. Typical residential systems are single-phase.
Standard Method
The detailed dwelling-load calculation method that applies demand factors to different load categories separately.
Related resourceSubpanel
A downstream panelboard fed from another overcurrent device or service equipment.
Supplementary Overcurrent Protection
Additional overcurrent protection for specific equipment that does not replace required branch-circuit protection.
6 terms
Thermal Trip
The portion of a breaker that responds to heat from overload current and trips with a time delay.
THHN
Thermoplastic High Heat-resistant Nylon-coated conductor insulation, commonly used in dry locations.
Related resourceTHWN-2
A thermoplastic conductor insulation rating for wet or dry locations, common in raceway wiring.
Related resourceThree-Phase
An AC system with three voltage waveforms spaced 120 electrical degrees apart. Common in commercial and industrial power distribution.
Title 24
California's building standards code. In electrical work, electricians often care most about the Title 24 energy rules that make some voltage-drop expectations mandatory in California.
Related resourceTransformer
A device that transfers electrical energy between circuits through electromagnetic induction and changes voltage levels.
Related resource2 terms
UF Cable
Underground feeder cable listed for direct burial and wet locations.
Utility Available SCA
The available short-circuit current at the utility or transformer source before downstream conductors reduce it.
Related resource4 terms
Volt
The unit of electrical potential difference.
Volt-Ampere
A unit of apparent power equal to volts multiplied by amperes.
Voltage Drop
The decrease in voltage from source to load caused by conductor impedance.
Related resourceVoltage Rating
The highest voltage at which a conductor, device, or piece of equipment is designed to operate safely.
1 term
Working Distance
The distance from a potential arc source to the worker's face or body used in arc-flash calculations.
Related resource1 term
XHHW
A cross-linked polyethylene conductor insulation commonly used in feeders and services for wet or dry locations.
Related resourceWhy these definitions matter in real calculations
Electrical mistakes often start with vocabulary mistakes. If someone mixes up ampacity with breaker size, FLC with FLA, or grounding-electrode work with equipment-grounding work, the calculation is usually wrong before the math even starts.
That is why the glossary is wired directly into calculators and support pages instead of living as a dead content island. The definition should help you take the next correct action, not just memorize one more term.
Where to go next after you have the definition
If the term is code-heavy, go to the code reference hub. If it is a workflow question, open the relevant calculator. If you want to see the term inside a full solution, the worked examples index is the best next stop.
Frequently Asked Questions
What does FLC mean in electrical work?
FLC means full-load current from the applicable motor table. It is the code value used for many motor circuit calculations and is different from the motor nameplate FLA.
What is the difference between GEC and EGC?
The GEC is the grounding electrode conductor that connects the electrical system to the grounding electrode system. The EGC is the equipment grounding conductor that runs with the circuit conductors to clear faults.
Why does SparkShift spell out Canadian Electrical Code instead of only saying CEC?
Because the audits found repeated confusion between Canadian Electrical Code and California code references. Spelling it out removes the ambiguity before someone relies on the wrong rule set.
Does this glossary replace the codebook?
No. It is a plain-English reference designed to help you move faster between calculators, code articles, and field decisions. The adopted code and project documents still control the real installation.
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