Direct answer: Choose a commercial Level 2 EV charger by working backward from the energy each vehicle must receive and the time it will remain connected. Then check three limits: the EVSE rating, the vehicle's onboard AC charger and the power the site can allocate. A higher nameplate rating only helps when all three allow it.

For a commercial project, “Which charger is fastest?” is usually the wrong opening question. A better question is: How many vehicles must leave with how much energy, by what time, within what site-power limit?

That distinction matters. A car parked for eight hours may not need the same solution as a delivery vehicle returning for two hours. Twelve high-power ports may be less useful than twenty lower-power ports if drivers cannot reliably gain access. And a 22kW AC charger cannot deliver 22kW to a vehicle whose onboard charger accepts 11kW.

This guide gives workplace, fleet, multifamily, hospitality, parking and distributor teams a repeatable way to specify a commercial AC charging system—without treating one market's voltage, connector or approval path as universal.

Terminology note: “Level 2” is mainly North American terminology. In IEC-oriented markets, buyers more often specify AC charging by mode, connector, phase and rated power—for example, Mode 3 Type 2 at 7, 11 or 22kW. Keep the user's search term, but write the purchase specification in the destination market's technical language.

Start with four project contracts, not a charger rating

A robust Level 2 project is four connected contracts. If any one is vague, the hardware quote is incomplete.

1. Vehicle and schedule contract

Record the vehicle models, normal arrival state of charge, required departure state of charge, arrival and departure windows, daily distance, and whether vehicles can be moved after charging. These inputs define the energy deficit and available dwell time.

2. Electrical contract

Record the service voltage and phase, spare capacity, upstream protection, feeder distance, allowable coincident load and the method for controlling demand. This defines how much power the site can offer—not merely how much an individual charger can request.

3. Physical-access contract

Record bay geometry, wall or pedestal location, cable reach, collision protection, drainage, lighting, accessible routes and any moving structures. A charger cannot serve a vehicle if the cable route conflicts with doors, walkways or a mechanical parking platform.

4. Digital-operations contract

Define who may charge, how users authenticate, whether energy must be measured for billing, which backend manages the stations, how faults are reported, who may reset a charger, and how firmware and security updates are handled.

These contracts turn “We need 20 Level 2 chargers” into a design brief that an equipment supplier, electrical engineer and operator can evaluate together.

The three ceilings determine actual AC charging power

AC charging has a constraint that is easy to miss: the vehicle converts the AC supply to DC through its onboard charger. The US Department of Energy describes this architecture directly, and notes that Level 2 is common in workplace and fleet settings. Its example is specific to a federal-site context, not a universal rating. (US DOE FEMP)

For planning, use this relationship:

Actual AC charging power ≤ the lowest of:

1. the EVSE's configured output;
2. the vehicle's onboard AC charging limit; and
3. the site's available or load-managed allocation to that port.

Worked example: why a 22kW label may deliver 8kW

Assume:

• EVSE setting: 22kW;
• vehicle onboard AC limit: 11kW;
• current site allocation to the port: 8kW.

The planning ceiling is 8kW. The charger is not defective; the site allocation is the active constraint. If the site later releases more power, the vehicle still cannot exceed its 11kW onboard limit.

This is why a supplier should not promise a universal number of kilometres or miles added per hour. Charging time depends on the vehicle, its battery and onboard equipment, the EVSE, and the electrical supply. The US Alternative Fuels Data Center makes the same dependency explicit. (AFDC)

Size power from energy deficit and dwell time

The first-pass calculation is intentionally simple:

Required average delivered power (kW) = energy required before departure (kWh) ÷ connected time (h)

Suppose a fleet vehicle normally returns needing 28kWh and remains connected for eight hours:

28kWh ÷ 8h = 3.5kW average delivered power

That does not mean a 3.5kW nameplate is the final selection. The design still needs to account for conversion losses, interruptions, colder or hotter operating conditions, late arrivals, operational reserve and the site's demand-control behavior. Those allowances should be explicit in the project calculation rather than hidden inside a generic “charging speed” promise.

Now change the schedule: the same 28kWh must be delivered during a two-hour turnaround.

28kWh ÷ 2h = 14kW average delivered power

A 7 or 11kW AC path no longer meets the simplified requirement. A 22kW AC option may work only if the vehicle accepts the needed AC power and the site can allocate it. Otherwise the project should evaluate DC charging or a mixed AC/DC architecture.

Use a range, not a single perfect day

For each vehicle group, calculate at least:

• a normal operating day;
• a high-energy day;
• a shortened dwell-time day; and
• a degraded mode in which one charger or network function is unavailable.

This reveals whether the project relies on ideal parking behavior. It also helps separate an occasional exception—which an operational rule or one faster charger may solve—from a system-wide requirement that changes the architecture.

Count port-hours before port-kW

Power per connector is only half the capacity question. Vehicles also need physical access for enough time.

Define one port-hour as one vehicle connected to one charging port for one hour. Then total the connection hours required inside the scheduling window.

Worked example: access becomes the limiting factor

Assume 12 vehicles each need six connected hours during an eight-hour overnight window:

• required connection capacity: 12 × 6 = 72 port-hours;
• theoretical capacity per continuously available port: 8 port-hours;
• minimum before any operating allowance: 72 ÷ 8 = 9 ports.

Nine ports is only the mathematical floor. Real planning must consider arrival overlap, vehicles that are not moved promptly, unavailable bays, maintenance and the operator's ability to enforce a schedule.

Now imagine the site buys four 22kW chargers. Even if each vehicle could finish faster, the solution fails whenever vehicles cannot reach a connector at the right time. Conversely, more intelligently managed lower-power ports may serve a long-dwell fleet better because every vehicle can remain plugged in while power is allocated over the full window.

The sequence is:

1. prove that enough vehicles can be physically connected;
2. prove that the energy can be delivered inside their dwell windows;
3. size the site and control system for coincident demand; and
4. add an operating allowance based on the site's real failure and parking rules.

7, 11 or 22kW: what changes in practice?

The labels below are documented configuration examples, not a claim that every market uses the same input supply. Exact model, connector, protection, metering and approval documents must be confirmed for the destination.

Choose 7kW when coverage is more valuable than headline power

Seven-kilowatt-class AC charging is often practical for employee parking, residential parking and overnight fleet dwell. It can allow a constrained site to connect more vehicles, especially when a load-management system distributes a fixed site limit. It is the wrong choice if the high-energy operating case cannot be completed inside the actual parking window.

Choose 11kW when the vehicle and three-phase context support it

An 11kW IEC-oriented configuration can be a useful middle ground: materially more energy during the same dwell period without automatically moving the project to DC. But the vehicle must accept it, and the destination supply must match the quoted model. In North America, do not convert the IEC phase/current description into a sales claim; use the specific regional model and document pack.

Choose 22kW only when the extra acceptance can be used

Twenty-two kilowatts is not automatically “future-proof.” If the target vehicles accept 7 or 11kW AC, the additional EVSE capacity remains unused. If the site must curtail every port during normal coincidence, the higher rating may add little operational value. It becomes useful when vehicle acceptance, dwell-time need and site allocation align.

Match the architecture to the parking mission

The Government of Western Australia's workplace guide uses the same core logic: duty cycle, vehicle use, dwell time, site power and space should drive technology and quantity; it also recognizes mixed AC/DC designs for mixed operational needs. Its local costs and program rules should not be exported to other countries. (WA workplace charging project guide)

Decide how multiple ports share the site limit

A bank of chargers creates a coincidence problem. Twenty nominal 11kW ports do not necessarily require the site to reserve 220kW continuously, but the quote must state what happens when all twenty vehicles request power.

Fixed current settings

Each EVSE is commissioned at a fixed limit. This is simple to understand, but the aggregate design must cover the credible simultaneous load. It may leave unused capacity when some ports are idle.

Static group sharing

A fixed power budget is divided among a known group of ports. This can increase port coverage without raising the group's maximum demand. The supplier must describe minimum allocation, recovery behavior, grouping rules and what occurs if the controller is unavailable.

Dynamic load management

The charging allocation changes in response to a measured or calculated site limit. This can coordinate charging with other building loads, but it introduces dependencies: metering, communications, control logic, fail-safe behavior and commissioning evidence.

Ask for a simultaneous-load schedule—not just a single-port rating. A useful schedule shows the group limit and the allocation at 1, 2, 5, 10 and full port occupancy, including any minimum current constraints.

Procurement trap: “Supports load balancing” is not a design. State whether the control is local or cloud-dependent, static or dynamic, per phase or total, and how charging behaves after loss of meter data, network or controller.

Specify the destination market before the connector

The phrase “Level 2 charger” does not identify one worldwide electrical or connector package.

North America

Commercial Level 2 projects commonly work from 208V or 240V service and must specify the exact vehicle connector path, including SAE J1772 or J3400 where applicable. The equipment rating, circuit design and continuous-load treatment belong in a locally engineered package. AFDC's charging-equipment overview is a useful US starting point, but it is not an installation design for a specific site. (AFDC)

IEC-oriented markets

Projects commonly distinguish single-phase and three-phase AC, Mode 3 operation and Type 2 interfaces. For example, the UK commercial-chargepoint specification describes 230V single-phase and 400V three-phase AC categories and requires the claimed output to reflect actual capacity, including simultaneous output for multi-outlet products. That is a UK program requirement, not a universal rule; use it as an example of why destination documents matter. (UK commercial chargepoint specification)

IEC 61851-1 defines general requirements for conductive charging equipment, but citing a standard does not prove that a quoted model is approved for a destination. Request the declaration, test reports and certificates that apply to the exact model, options and shipment. (IEC 61851-1)

What the purchase order should name

• destination country and installation jurisdiction;
• service voltage, phase, frequency and earthing arrangement;
• exact connector or socket and cable arrangement;
• rated and configured current;
• required protection, isolation monitoring or residual-current provisions as applicable;
• metering and billing requirements;
• enclosure and environmental requirements;
• applicable product documents and local installation approvals;
• language, labels and emergency instructions.

Do not approve an order using only “11kW Level 2 charger.”

Treat the backend as an operating system, not a checkbox

Networking matters when a site must control access, collect data, manage demand, bill users or support remote service. But “OCPP supported” leaves critical questions unanswered.

The Open Charge Alliance maintains distinct OCPP versions and a certification program for specific implementations. Therefore a project should identify the version, tested profiles and backend relationship rather than treating the acronym as proof of interoperability. (Open Charge Alliance FAQ)

Ask the charger and CSMS providers to demonstrate:

1. exact OCPP version and transport method;
2. backend name and tested firmware version;
3. boot, authorization, start/stop, meter values and transaction records;
4. remote reset, availability and configuration controls;
5. offline authorization and transaction recovery;
6. smart-charging or power-management messages actually used by the project;
7. certificate, credential and key-update process;
8. firmware signing, update and rollback behavior;
9. event logs, clock synchronization and data export;
10. ownership of SIMs, cloud accounts, licenses and operating data.

For a private depot that uses local access and no energy billing, a simpler architecture may be more reliable. For public or multi-tenant charging, identity, tariff, payment, privacy, uptime support and audit records become part of the commercial system—not optional interface details.

Design the parking space around the charging task

Hardware selection should follow a site walk or a dimensioned plan.

• Mounting: confirm wall strength, pedestal foundations, service access and replacement clearances.
• Cable reach: test the connector path against vehicle inlet positions without crossing walking routes or dragging on moving equipment.
• Collision and weather: locate bollards, wheel stops, drainage and enclosure openings without blocking operation or maintenance.
• Accessibility: coordinate bay dimensions, route, reach range, controls, screen readability and cable handling with the destination's accessibility requirements.
• Civil and electrical routing: measure trench, conduit and feeder paths; verify fire compartments, ventilation and penetrations.
• Operations: define snow, cleaning, parking enforcement, cable inspection and fault-response responsibilities.

The equipment manufacturer can document its product. A qualified local designer and installer must still determine how that equipment is installed under the jurisdiction's electrical, civil, fire, accessibility and permitting requirements. The UK guidance explicitly separates final installation from the chargepoint's equipment specification; the same scope boundary is good procurement practice elsewhere even though the rules differ. (UK commercial chargepoint specification)

What real project images reveal—and what they do not

Repeated wall-mounted bays: design for consistent access

Supplied HG Power project records identify this as a 331-unit 7kW AC deployment. The image supports a physical observation: repeated bay placement makes cable reach, feeder routing and parking discipline system-level decisions. It does not establish simultaneous output, utilization or operating results.

At this scale, small installation choices repeat hundreds of times. Connector height, cable loop, bay marking, protection routing and equipment spacing should therefore be resolved on a typical-bay detail before mass installation.

Mechanical parking: clearance becomes a first-order input

Supplied project records identify a 168-unit mechanical-parking deployment. The image is used only to show the importance of moving-platform clearance, cable routing and charger reach; it makes no performance or acceptance claim.

Mechanical parking adds moving structures and atypical vehicle positions. The design team should review every platform state, cable path and maintenance zone—not only the parked state shown on a general plan.

Diagnose common Level 2 design failures

HG Power's documented AC configuration scope

HG Power's Product Configuration Guide, version 20250705, presents:

• 7–22kW wall-mounted and column-mounted AC families; and
• 22–44kW floor-mounted AC families.

This article focuses on commercial 7, 11 and 22kW selection because those ratings align with the Level 2 / commercial AC search decision. The wider AC portfolio does not mean every model shares the same voltage, connector, screen, authentication, OCPP, metering, protection or approval package.

The controlled product list separates IEC-oriented 230V single-phase 7kW, 400V three-phase 11kW and 400V three-phase 22kW examples from North American 240V model paths. For public comparison pages, that distinction is more useful than merging every option into one specification row.

Available functions shown in the guide include configuration-dependent screen, authentication, communications and OCPP options. They should be quoted by exact model and tested function. Buyers can review the 7kW AC charger configuration and the 7/11/22kW AC charger family, then confirm the final destination-specific configuration with HG Power.

Compliance boundary

Compliance documents are model-, configuration-, market- and date-specific. This guide therefore does not make a blanket certification claim. Before purchase approval, request the current declaration, test reports and certificates that name the exact model and options for the destination market; confirm document validity and coverage as part of commercial review.

Copy this 12-input AC Charging Design Brief

Send these inputs with the RFQ. If an answer is unknown, mark it “to be surveyed” rather than letting a supplier assume.

1. Country and installation location: city/region, indoor or outdoor, public or private access.
2. Vehicle list: model, quantity, connector and maximum onboard AC charging power.
3. Energy requirement: typical and high-case kWh needed per vehicle before departure.
4. Schedule: arrival, departure, dwell and whether vehicles can be moved after charging.
5. Port demand: number of vehicles that must connect concurrently and expansion plan.
6. Electrical supply: voltage, phase, frequency, earthing arrangement and measured spare capacity.
7. Demand limit: maximum coincident EV charging load and other loads to coordinate.
8. Physical layout: scaled plan, bay dimensions, cable routes, feeder distances and mounting preference.
9. User and payment model: private fleet, employees, tenants, guests or public users; free, allocated or paid energy.
10. Backend: CSMS name, OCPP version, connectivity, offline behavior and required reports.
11. Environment and compliance: temperature, altitude, humidity/corrosion, enclosure, accessibility and destination document requirements.
12. Acceptance and support: factory tests, site tests, training, spares, response workflow and warranty terms requested in the commercial offer.

With these inputs, the supplier can return a configuration matrix rather than a generic brochure.

Require a configuration matrix and acceptance pack

The quotation should show, per exact model:

• model code and revision;
• rated and configured power/current;
• input voltage, phase and frequency;
• connector, cable length and output count;
• simultaneous output and power-sharing rules;
• protection functions and upstream requirements;
• enclosure/environmental ratings and their test basis;
• user interface, authentication and metering;
• OCPP version, CSMS test status and connectivity hardware;
• optional versus standard functions;
• declaration, certificate and report list with model coverage and validity;
• supplied drawings, manuals, labels and language;
• factory acceptance test and site commissioning responsibilities;
• warranty scope, exclusions, spares and service escalation.

Before rollout, run a pilot or representative acceptance test that covers normal charging, simultaneous occupancy, load-management limits, loss and restoration of communications, offline sessions, emergency/fault behavior, transaction records and the operator's actual support route.

When Level 2 is not the right primary solution

Do not force an AC design when the operating requirement says otherwise. Evaluate DC or a mixed architecture when:

• high energy must be delivered during short, fixed turnarounds;
• vehicles cannot remain parked for the required connection hours;
• rapid public turnover is the commercial promise;
• an exception vehicle repeatedly disrupts the AC schedule; or
• the target vehicles' operating pattern makes onboard AC limits the bottleneck.

If the AC sizing test fails, move the project into a separate AC-versus-DC architecture review. Keep that decision outside the Level 2 equipment quotation so a supplier cannot solve a short-dwell requirement merely by increasing the AC nameplate rating.

Frequently asked questions

What is a Level 2 EV charger?

In North American usage, Level 2 is AC EVSE supplied from a higher-voltage AC circuit than Level 1; the vehicle's onboard charger converts that AC to DC for the battery. In other markets, specify AC mode, connector, phase, current and kW instead of relying on the Level 2 label.

Is a 22kW Level 2 charger always faster than 11kW?

No. Delivered power cannot exceed the vehicle's onboard AC limit or the site's current allocation. A vehicle limited to 11kW cannot use 22kW from the EVSE.

How many Level 2 chargers does a commercial site need?

Calculate vehicle energy needs and connection hours inside each operating window. The port-hours method identifies the minimum access capacity; then add a project-specific allowance for overlap, unavailable bays, maintenance and parking behavior.

Can 7kW charge a commercial fleet overnight?

It can when each vehicle's required energy divided by connected time fits within the delivered-power envelope. Verify the high-energy and shortened-dwell cases rather than using a universal yes/no rule.

Does every 11kW AC charger require three-phase power?

No universal mapping should be assumed. Documented IEC-oriented 11kW configurations commonly use 400V three-phase at 16A, while HG Power's North American register uses a separate 240V model path. Quote the exact destination model.

Do commercial Level 2 chargers need OCPP?

Not always. A simple private site may use local controls. OCPP becomes useful when a CSMS must manage identity, sessions, data or smart charging, but the project must still specify version, backend, security and tested functions.

Can load management avoid a service upgrade?

It may reduce or cap coincident EV demand, but it is not a guaranteed substitute. An engineer must assess the service, existing loads, operating schedule, minimum charging requirement, control reliability and local rules.

Who is responsible for installation compliance?

The manufacturer documents the equipment and its installation requirements. A qualified local designer and installer must integrate it into the site under the destination's electrical, civil, fire, accessibility and permitting rules.

Build the RFQ around the operating day

A commercial Level 2 project succeeds when vehicles receive the required energy on schedule—not when the datasheet displays the largest number. Start with energy deficit, dwell and port-hours. Apply the three ceilings. Then lock the destination-specific electrical, connector, backend, physical and documentation package.

If you send HG Power the completed 12-input AC Charging Design Brief, the team can review whether a 7, 11 or 22kW configuration—or a mixed AC/DC architecture—matches the project. Contact HG Power for a model-specific configuration review.

Sources and review

External references used in this guide:

• US DOE FEMP — EVSE Infrastructure for Federal Fleets
• US Alternative Fuels Data Center — Charging Stations
• IEC 61851-1:2017 official publication page
• Government of Western Australia — Project Guide for Workplace Charging
• UK commercial chargepoint minimum technical specification
• Open Charge Alliance FAQ

First-party sources: HG Power Product Configuration Guide Ver. 20250705; Overseas Standard EV Charger Product List V2.6 dated 2025-07-02; model-specific compliance records and supplied project image folders. Product and document scope was checked against the internal evidence register for this article.

Technical reviewer: Marvin
Last reviewed: August 12, 2026