The plain-English EV charging glossary.

Charging an electric vehicle using alternating current. Level 1 (120V) and Level 2 (208V or 240V) are both AC. The charger sends AC power to the vehicle, where the vehicle's onboard charger converts it to DC for the battery. AC charging is generally limited to under ~22 kW because the vehicle's onboard charger is the bottleneck.

A protective coating applied to internal charger electronics to prevent condensation damage in humid or temperature-cycling environments. Typical for outdoor-rated DC fast chargers in coastal or tropical deployments.

Restricting who can use a charger. Methods: RFID lists, mobile app accounts, geofenced authorization, employee codes. Used at workplace, fleet, and member-only sites.

Americans with Disabilities Act requirements for accessibility. For EV chargers at public sites, this typically means at least one accessible parking space with a charger, an accessible route from space to charger, the connector and screen reachable from a wheelchair (max 48 inches above grade), and no protrusions above 27 inches that aren't detectable by cane.

The US Department of Energy's database of clean-fuel programs, including federal and state EV charging incentives. The starting point for any US rebate research.

The flow rate of electrical current. EV chargers are rated by their input amperage (e.g., a 40-amp Level 2 charger). Higher amperage means more power delivered, but also requires a larger circuit and breaker. Often abbreviated as A.

The process of identifying who is allowed to start a charging session. Common methods: RFID card, mobile app, plug-and-charge (ISO 15118), credit card, or autocharge. The authorization step is what links a session to a billing account.

A simpler precursor to ISO 15118 plug-and-charge. The charger identifies the vehicle by its EVSE ID or MAC address and starts a session automatically. Less secure than ISO 15118 but easier to deploy.

When an EV warms or cools its battery before arrival at a fast charger to enable maximum charging speed. Most modern EVs do this automatically when navigation routes to a known charger location.

An EV charging architecture where a stationary battery sits between the grid and the chargers. The grid feeds the battery at a steady rate; the battery feeds the chargers at burst rates. Lets a small grid service support high-power charging by absorbing peak demand. MÖTEN's XEYAR system is one example.

The process of charging a driver for a session. Includes pricing model (per kWh, per minute, flat fee), payment processor integration (Stripe, Square, Adyen), and receipt generation. eMÖTEN CMS includes billing on every MÖTEN charger.

The electrical box where individual circuit breakers terminate. Each EV charger requires a dedicated breaker. Panel capacity (total amperage and slot count) limits how many chargers can be added without panel work.

A federal procurement requirement that a specified percentage of components by cost in federally funded projects be US-manufactured. Increasingly applied to EV charging programs. Compliance is checked at the component level, not the assembly level.

The DC fast charging connector standard used in North America. Combines an SAE J1772 AC connector on top with two large DC pins below. Most non-Tesla EVs in the US/Canada used CCS1 before the NACS transition.

The DC fast charging connector standard used in Europe and parts of South America. Combines a Type 2 (Mennekes) AC connector on top with two large DC pins below. Functionally equivalent to CCS1 but with a different physical shape.

Independent testing confirming a charger meets safety and performance standards. Common certifications: UL 2594 (Level 2), UL 2202 (DC fast), CSA, FCC, ENERGY STAR, IEC 61851. Required by most utility rebate programs and building codes.

An older DC fast charging connector standard, originally Japanese. Largely deprecated in North America in favor of CCS and NACS. Still common on legacy Nissan Leaf and Mitsubishi vehicles.

OCPP terminology for a single charging station, which may have one or more connectors (ports). One charge point with two ports is one OCPP charge point with two EVSEs.

A safety device that interrupts current when it exceeds a set amperage. EV chargers require dedicated circuit breakers sized to the charger's continuous load (typically 125% of the charger's rated current per NEC Article 625).

A category of US federal tax credits including the Section 30C Alternative Fuel Vehicle Refueling Property Credit, which currently provides up to 30% of qualifying EV charging equipment costs. Eligibility, caps, and bonus tiers (e.g., low-income census tracts) vary.

Software that monitors and controls EV chargers — sessions, billing, faults, reports, firmware. eMÖTEN CMS is included at $0/month on every MÖTEN charger; non-MÖTEN OCPP chargers can be added on paid tiers.

The post-installation process of bringing a charger online — connecting to the CMS, confirming OCPP heartbeats, validating sessions, completing AHJ inspection. The handoff between installation and operation.

Protective tubing that carries electrical wires from the panel to a charger. Conduit type (PVC, EMT, rigid steel) and size are dictated by NEC based on environment, wire size, and run length.

The physical plug at the end of a charger's cable that plugs into a vehicle. Common types: J1772 (Level 2 AC), NACS (Tesla / new North American standard), CCS1, CCS2, CHAdeMO.

A mechanism that locks the connector to the vehicle during a session, preventing tampering or removal. Standard on most modern EVs; the vehicle controls lock/unlock via the control pilot signal.

A heavy-duty relay that opens or closes the high-current circuit in a charger. Activates when authorization completes and the vehicle requests charging.

Per NEC, a load expected to operate at maximum current for three or more hours. EV chargers are continuous loads, which is why circuits must be sized at 125% of charger rating.

The low-voltage signal between charger and vehicle that handles handshake, current limits, and state changes. Required by SAE J1772 and other AC charging standards. Often called 'pilot signal.'

The ratio of energy delivered to a vehicle versus energy drawn from the grid. AC charging efficiency is typically 88–92%; DC fast charging is typically 92–96% from grid to battery; battery-buffered systems add a small additional round-trip loss (5–10%) for energy that passes through the buffer battery.

The cable assembly between a charger and the vehicle, including the plug. Cord sets are rated for current, length, and environment (e.g., crush-resistant for industrial use).

OCPP 2.0.1's term for what was called a 'central system' in OCPP 1.6. Functionally the same as CMS — the back-office software that manages chargers.

Direct-current charging delivered at 50 kW or higher, bypassing the vehicle's onboard charger and feeding DC directly to the battery. Typical session: 20–40 minutes for 80% charge. Used at corridor stops, fleet quick-turn depots, and premium retail hubs.

A utility billing component charged for the highest 15-minute interval of grid draw in a billing period. Most US commercial tariffs include them. EV charging can drive significant demand charges, which is one reason battery-buffered systems are economically attractive.

Utility programs that pay sites to reduce load during peak grid events. Some EV charging deployments participate by curtailing charging during called events; the revenue can offset operating costs.

When a charger reduces its output below rated capacity, typically due to thermal management, low ambient voltage, or a load-management directive. Derating is normal and protects the equipment.

In a battery-buffered or shared-bus system, the customer-facing unit with the connector that delivers power to the vehicle. Distinct from the power conversion stage and battery, which sit elsewhere on site.

The customer-facing enclosure of a charger, containing the connector(s), screen, payment hardware, and connector storage. In battery-buffered systems, the dispenser is separate from the power conversion stage.

The duration a vehicle is parked at a charging location. Sets the practical upper bound on charger size — there's no point in faster charging than the dwell time can absorb. See our blog post on choosing chargers by dwell time.

MÖTEN evfc's proprietary Charger Management System. Included at $0/month on every MÖTEN charger — no monthly fees, no per-port fees, no transaction markup on payment processor fees. Manages session control, billing, reporting, OCPP integration, and firmware updates.

A US EPA certification for energy-efficient Level 2 chargers. Some utility rebate programs require ENERGY STAR certification.

The formal regulatory term for an EV charger. Includes everything from the wall connection to the cord and plug. One charger with two ports has two EVSEs.

A unique identifier assigned to each charging port. Used by OCPP, billing systems, and roaming networks (Hubject, OCPI) to track sessions.

Current that flows in a fault condition (short circuit, ground fault). Equipment must be rated to interrupt or withstand the available fault current at its location, typically calculated by a licensed electrician.

The Alternative Fuel Vehicle Refueling Property Credit under US Internal Revenue Code Section 30C. Provides up to 30% of qualifying EV charging equipment and installation costs, with per-property caps and bonuses for low-income census tracts. Read more: our rebate decoder post.

Embedded software running on the charger itself. Updated over the air via the CMS connection. Firmware updates can fix bugs, add features (e.g., new payment methods), and address security vulnerabilities.

EV charging deployed at a depot or yard for a managed fleet of vehicles. Optimization priorities differ from public charging: predictable nightly schedules, deep load-management integration, and low operating cost per mile.

A safety device that detects current leakage to ground and trips the circuit. Required on certain EV charging circuits per NEC. Distinct from a standard circuit breaker, which trips on overcurrent.

EV charging that draws power directly from the utility grid, with no on-site battery buffer. The conventional architecture; works well when the grid service can handle the peak load.

An installation where the charger is permanently wired to the building's electrical system, with no plug. Most commercial Level 2 and all DC fast installations are hardwired. Contrast with plug-in installations, which use a NEMA outlet.

A European-origin EV charging roaming platform that lets drivers use one account across many networks. Implemented via the OICP protocol. Common in Europe; growing in North America.

A per-minute fee charged after a charging session completes if the vehicle remains plugged in. Used at busy public sites to free up the port. Typically $0.40–$1.00 per minute.

The process of formally connecting a customer's electrical system to the utility grid for new or upgraded service. Required for new DC fast charging sites and may take 6–18 months.

Ingress Protection rating per IEC 60529. The first digit (0–6) rates dust/solid protection; the second (0–9) rates water protection. Most outdoor commercial chargers are IP54 or IP65; corridor and harsh-environment chargers may be IP67.

An international standard for vehicle-to-charger communication, supporting plug-and-charge, smart charging schedules, and bidirectional energy flow (V2G). Required for OCPP 2.0.1's plug-and-charge feature.

The standard Level 2 AC charging connector in North America. Five pins: two AC line, ground, control pilot, proximity. Compatible with all non-Tesla EVs sold in North America via direct connector or NACS adapter.

Apparent power — the product of voltage and current without accounting for power factor. Used to size service entrances and transformers. For purely resistive loads, kVA equals kW.

kVA is apparent power; kW is real power. The ratio (power factor) matters for sizing transformers and service entrances. Modern EV chargers have high power factors (>0.95), so for most practical EV charging sizing, kVA ≈ kW.

A unit of power equal to 1,000 watts. Charger output ratings are in kW: a 7.7 kW Level 2 charger delivers up to 7,700 watts; a 180 kW DC fast charger delivers up to 180,000 watts.

A unit of energy equal to 1 kW delivered for 1 hour. EV battery capacity and session energy are measured in kWh. A typical EV battery holds 60–100 kWh; a typical full charge delivers 30–80 kWh.

California's market-based program for reducing carbon intensity in transportation fuels. EV charging operators in California can generate LCFS credits, which they sell to other regulated parties as ongoing revenue.

Charging from a standard 120V household outlet. Adds roughly 3–5 miles of range per hour. Slow but requires no special equipment. Common for emergency/portable use; rarely deployed at commercial sites.

Charging from a 208V or 240V circuit (commercial or residential 240V). Power output 3.3–22 kW. Adds roughly 15–80 miles of range per hour. Standard for workplaces, hotels, multifamily, and most retail.

Insurance covering injury or property damage from charger operation. Required at most public-access sites. Typically bundled with the property's general liability policy at no additional charge.

A professional electrician certified by the state or province to perform electrical installations. Required for most commercial EV charger installations and some residential ones. Verify before hiring.

Software-controlled distribution of available power among multiple chargers to stay within a circuit, panel, or service capacity. Lets a small service support many chargers as long as not all run at full power simultaneously.

An automated reduction in charger output triggered by a utility signal, demand-response program, or local power event. Distinct from load management, which is continuous; load shedding is episodic.

A utility program where the utility funds the electrical infrastructure (conduit, service upgrade, panel) up to and sometimes including the charger pad — but not the charger itself. The site host pays for the charger only. Common in California, New York, and several other states.

The factory warranty on charger hardware, typically 2–5 years. Distinct from extended warranties (sold separately) and installer workmanship warranties (covering installation defects).

A small, controllable subset of a grid that can operate independently from the main utility (islanded). EV charging deployments paired with on-site solar and battery storage may be configured as microgrids for resilience.

EV charging at apartments, condos, and other multi-unit residential properties. Often involves shared circuits, load management, and submetering to allocate energy costs to individual residents.

The connector originally developed by Tesla and adopted by SAE as J3400 in 2023. Smaller and lighter than CCS1, with both AC and DC charging on the same physical port. Most major automakers committed to NACS for North American vehicles starting in the 2024–2026 model years.

The US national standard for safe electrical installation, published by NFPA. EV charging installations must comply with NEC Article 625. Specific provisions cover circuit sizing, GFCI requirements, grounding, and disconnects.

The National Electrical Manufacturers Association standard for AC outlets. Common EV-charging-relevant types: NEMA 14-50 (240V, 50A — typical for Level 2 plug-in) and NEMA 6-50 (240V, 50A, no neutral). Outlet type determines charger compatibility.

A monthly charge from a CMS provider per port to use their software platform. Common in legacy charging networks ($10–$30/port/month). Notably absent on MÖTEN chargers, where eMÖTEN CMS is included at $0/month.

A US federal program providing $5 billion over five years to build a national EV charging network along major highways. State-administered, with strict equipment, uptime, and reliability requirements.

An open protocol for inter-network communication — letting one charging network's app authorize and bill sessions on another network's chargers. Enables roaming, similar to mobile phone roaming agreements.

The open standard communication protocol between EV chargers and their management systems. MÖTEN chargers support OCPP 1.6 and 2.0.1. Read more in our OCPP 1.6 vs 2.0.1 deep-dive.

The DC power conversion equipment that sits in the charging cabinet, not the vehicle. Used in DC fast charging, where conversion happens on the charger side rather than the vehicle side.

The AC-to-DC converter inside an EV that handles Level 1 and Level 2 charging. Maximum AC charging power is set by this onboard charger — typically 7.7–22 kW depending on the vehicle.

Ongoing costs to operate a charger — energy, network fees, maintenance, software. Lower OPEX is one reason MÖTEN's $0/month CMS on MÖTEN chargers matters for long-term TCO.

Firmware or software updates pushed to chargers remotely via their CMS connection, without on-site visits. Standard for modern chargers; eliminates the need for technicians for most software fixes.

An individual parking space designated for EV charging. Must meet ADA accessibility requirements when public, with appropriate signage and pavement markings.

A free-standing column mount for a charger, used where wall-mounting isn't practical (parking lots, fleet yards). Pedestals require a concrete pad and conduit run from the service entrance.

Whether an electrical service uses one or three live conductors. Single-phase (residential and small commercial) supports up to ~22 kW Level 2. Three-phase (most commercial and industrial) is required for higher-power AC charging and almost all DC fast charging.

An ISO 15118-based feature where a vehicle and charger negotiate identity and billing automatically when plugged in — no app, card, or interaction required. Requires both vehicle and charger to support ISO 15118.

A single connector on a charger. A charger with two cables has two ports, capable of two simultaneous sessions (though not necessarily both at full power, depending on the charger's internal architecture).

The ratio of real power (kW) to apparent power (kVA). DC fast chargers typically have power factors above 0.95. Low power factor wastes utility capacity and may incur tariff penalties.

A specific form of load management where two or more ports on the same charger split available power dynamically. If only one port is active, it gets full power; if two ports are active, each gets half.

Branding a charger or CMS dashboard with the site host's branding rather than the equipment manufacturer's. Common for premium retail and corporate fleet deployments.

The final list of items to complete before a project is officially closed — signage, paint touch-ups, documentation, training. Tracking and closing the punch list is the final step before commissioning.

Software features for managing waiting drivers when all ports are occupied — virtual queuing, push notifications when a port frees up, time-limited reservations. Common at high-utilization sites.

The maximum power a charger can deliver under ideal conditions. Real-world output may be lower due to vehicle limits, ambient temperature, voltage variations, or load management.

A post-purchase reimbursement, distinct from a tax credit (claimed at tax time) or grant (paid upfront). Many state and utility EV charging programs are structured as rebates. See our rebates hub.

A contactless authentication method using a card or fob with an embedded chip. Common for EV charger authorization at workplace, fleet, and managed-access sites.

Selecting charger power matched to actual use — neither more nor less than the dwell time and energy demand requires. Avoids paying for overcapacity and avoids underserving demand.

Profit relative to upfront cost, typically expressed as a percentage or payback period. EV charging ROI varies widely: corridor DC fast can pay back in 2–4 years; workplace Level 2 often relies on amenity value rather than direct revenue.

The Society of Automotive Engineers standard that defines the Level 2 AC connector and its communication protocol. See also: J1772.

The SAE standardization of Tesla's North American Charging Standard, ratified in 2023. Defines NACS as an open, non-proprietary connector standard.

Where the utility's wires connect to a building's electrical system. The service entrance's amperage rating sets the upper bound on what the building can draw. Increasing it usually requires utility coordination and a transformer upgrade.

A single charging event from plug-in to plug-out. Sessions have a unique ID, start/end timestamps, energy delivered (kWh), peak power, authorization method, and billing detail.

Generic term for any charger control beyond simple on/off — load management, scheduled charging, demand response, peak shaving. OCPP 2.0.1 added significantly more granular smart charging profile support than 1.6.

The current battery charge level as a percentage. Modern EVs report SOC to chargers via OCPP/ISO 15118, allowing the charger to manage charging speed and predict completion time.

An EV charging deployment paired with on-site solar generation and battery storage. Reduces grid demand, can island during outages, and may qualify for additional incentives.

Measuring individual charger usage separately from a building's main meter. Required for accurately allocating energy costs in multifamily and shared-tenant deployments.

Generic term for any government financial support — includes tax credits, rebates, grants, and make-ready programs. Distinct from utility incentives only in funding source.

The published rate structure a utility uses to bill customers — including energy charges ($/kWh), demand charges ($/kW), fixed fees, and time-of-use periods. EV charging economics are highly sensitive to which tariff applies.

A reduction in tax liability claimed when filing taxes. Distinct from rebates (post-purchase reimbursement) and grants (upfront payment). The federal 30C credit is a tax credit.

All costs of owning and operating a charger over its lifecycle — hardware, install, energy, maintenance, network fees, software fees. Used to compare options across different vendors and architectures.

An AC power system using three live conductors offset by 120 degrees. Standard for commercial and industrial sites. Required for higher-power AC charging and most DC fast charging.

Utility rate structures where energy costs vary by time of day. EV charging deployments can lower operating costs by scheduling charging to off-peak windows.

A device that converts voltage from one level to another. Utility transformers step down distribution voltage (e.g., 12,000V) to building service voltage (208V or 480V). Adding high-power chargers may require transformer upgrades.

A brief voltage spike or drop. Surge suppression and transient voltage surge suppressors (TVSS) protect chargers from damage. Standard in commercial-grade installations.

The Underwriters Laboratories safety standard for DC fast charging equipment. Required for almost all commercial DC fast deployments in the US.

The Underwriters Laboratories safety standard for Level 2 AC charging equipment. Required by most US utility rebate programs and building codes.

Underwriters Laboratories certification that a product meets specific safety standards. UL-listed equipment is required by many building codes and rebate programs.

The percentage of time a charger is operational and available to drivers. Commonly required at 97% or higher in NEVI-funded projects. Uptime depends on hardware reliability, software stability, and maintenance response time.

A contractual commitment from a service provider to maintain charger availability above a stated percentage. NEVI-funded projects require uptime guarantees, typically 97%+.

A rebate offered by a local utility company (rather than a state or federal program). Often the most generous rebates available, but eligibility is restricted to customers in the utility's service territory.

An architecture where parked EVs send energy back to the grid during peak demand events, earning revenue for vehicle owners. Requires bidirectional chargers and ISO 15118-20 compatibility. Still emerging at commercial scale.

Using an EV's battery to power a building during a grid outage. Requires bidirectional charging hardware and a transfer switch. Available on a small number of vehicle models, expanding rapidly.

Using an EV's battery to power external devices via a built-in outlet on the vehicle. No charger needed; the vehicle has its own AC outlet. Common on Hyundai Ioniq 5, Ford F-150 Lightning, and others.

The electrical pressure pushing current through a circuit. EV chargers operate at common voltages including 120V (Level 1), 208V or 240V (Level 2), and 480V (commercial DC fast). Higher voltage allows higher power at lower current.

The reduction in voltage along a wire run due to electrical resistance. NEC limits voltage drop to 3% on branch circuits. Long conduit runs to chargers may require larger wire to stay within limits.

Visible variation in lighting caused by sudden voltage changes when a high-power load (like DC fast charging) starts or stops. May require utility-side mitigation in weak service areas.

Generic term for a wall-mounted Level 2 charger. Smaller and cheaper to install than pedestal-mounted units; appropriate for residential, workplace, and multifamily where a wall is available.

Manufacturer or seller commitment to repair or replace defective equipment. EV charger warranties typically run 2–5 years, with 10-year warranties available on some commercial-grade hardware. Read the fine print: parts vs. labor, on-site vs. depot repair.

The base unit of electrical power. One watt = one volt-amp of real power. Most EV charging discussions use kilowatts (kW = 1,000 W) or megawatts (MW = 1,000,000 W).

Connecting a charger to its CMS via Wi-Fi rather than cellular or Ethernet. Cheaper but less reliable for outdoor commercial sites — Wi-Fi range is shorter outdoors than buyers often expect.

EV charging deployed at workplaces for employee use. Typically Level 2 with long dwell times. Often subsidized by the employer as a benefit; may be free, paid, or shared-cost.

MÖTEN evfc's patent-pending battery-buffered charging architecture. A 100A standard service can drive up to 720 kW of EV charging, eliminating the typical 6–18 month utility upgrade timeline. Read more on the XEYAR product page and our engineering deep-dive.

Zero Emission Vehicle Infrastructure Program. A Canadian federal program supporting EV charging deployment. Distinct from US programs but operationally similar to NEVI.