Reviews
Part of A Planning Order for Multifamily EV Charging
Multifamily EV charging specs: the fields to compare
Compare multifamily EV charging specs field by field: electrical, listing, network protocol, connector, cable length and the parts that fail.
What to take away
- The headline kilowatt figure describes one port with nothing else running. It is not what residents will get.
- Maximum output is not continuous output, and neither is shared across every port at once.
- Connector and cable length decide whether a car can physically reach the unit, which no amount of output fixes.
- Price the parts that fail, because that is what the property lives with in year two.
Two chargers advertising the same output can behave completely differently once four cars plug in and the network drops. Spec sheets are written to make that hard to see.
So read the hardware field by field, and compare the service a resident receives, not the largest number in the brochure.
Read the electrical fields first
Put the electrical fields side by side before trusting any output claim. Each row of the table is a place where two sheets can look alike and differ in practice.
Electrical fields to compare
Specification
- Input and output
- Voltage, phase, amps
- Circuit arrangement
- Dedicated or shared
- Load management
- Local or cloud
- Connectors
- Vehicle compatibility
- Mounting
- Wall or pedestal
- Enclosure
- Outdoor rating
What to verify
- Input and output
- Max continuous output
- Circuit arrangement
- Panel requirements
- Load management
- Failure behavior
- Connectors
- Cable replacement
- Mounting
- Collision protection
- Enclosure
- Tamper resistance
| Specification | What to verify |
|---|---|
| Input and output | Voltage, phase, amperage, and maximum continuous output |
| Circuit arrangement | Dedicated or shared circuits, and what the panel must provide |
| Load management | Local or cloud control, what happens on failure, expansion ceiling |
| Connectors | Vehicle compatibility, cable length, how a damaged cable is replaced |
| Mounting | Wall or pedestal, cord storage, collision protection |
| Enclosure | NEMA enclosure type (for example 3R or 4X), temperature range, resistance to tampering |
Two more fields separate units that look alike on paper. Ask which listing the unit carries, such as UL 2594 for electric vehicle supply equipment. Ask which Open Charge Point Protocol (OCPP) version a networked unit speaks, so you can see whether it can work with another network provider.
Never assume maximum output is continuous, or that it is available to every port at the same time. Both assumptions are usually wrong, and both are usually left unstated rather than denied.
The wiring itself falls under NEC Article 625. Ask the vendor and your electrical designer to show how the proposal meets it and the local inspector's requirements.
The U.S. Department of Energy's Alternative Fuels Data Center (AFDC) is a useful sanity check here. It says Level 2 equipment offers charging through 240 V service, typical in residential applications, or 208 V, typical in commercial applications.
Level 1 uses a 120 volt AC plug, so it is rarely a shared answer, and a Level 2 unit's real output depends on the circuit and load management.
Check the connector question properly
Connector standards keep moving, and a building installed today outlasts today's mix of cars. Three names matter: SAE J1772 for the older AC connector, NACS/J3400 for Tesla's connector that other automakers are adopting, and CCS1 for the older DC fast-charging connector.
The Joint Office of Energy and Transportation notes that SAE International published the SAE J3400 connector standard in December 2023, based on the NACS connector. Read its summary before you commit to hardware for the next decade.
Adapters are not a neutral solution. They introduce a failure point and a safety question, so ask what the vendor supports rather than assuming that any car can use any port.
Measure the cable against the worst-parked bay
Cable length decides whether a car parked nose-in on the far side of a space can reach the unit at all, and drivers park inconsistently. Ask for the cable length in feet, because 18 and 25 feet are common, and measure the worst-parked bay before you accept it.
A longer cable is heavier to handle and easier to damage. Choose the length for the worst-parked car in the space the unit serves, not for the best-parked one.
Then ask how a damaged cable is replaced: on site or at a depot, by whom, and at what price. The answer belongs in the comparison next to the output figures.
Separate the things that fail from the things that impress
Most of what goes wrong in year two is not electrical, and the upkeep those parts actually need is worth pricing while you are still choosing between units.
What fails in year two
- Cablesrun over, yanked, vandalized
- Connectorscycle ratings, latch serviceable
- Screens and card readersfallback behavior
- Firmwareupdates, deferral, bricking risk
- Enclosureweather, salt, impact, humidity
- Cables.They get run over, yanked and vandalized. Ask whether a cable can be replaced on site, by whom, and what it costs.
- Connectors.Ask about cycle ratings and whether the latch is a serviceable part.
- Screens and card readers.The most exposed components and often the first to fail. Ask what the unit does when the reader dies. Does charging stop, or does it fall back to open access?
- Firmware.Ask how updates arrive, whether they can be deferred, and whether a failed update can brick the unit.
- Enclosure.In a lot, a unit is exposed to weather, salt and impact. In a garage, to humidity and the occasional bumper. The enclosure options differ more than the sheets suggest.
Start every spec sheet from the same site numbers
Specs only compare when every vendor starts from the same site facts. Send each bidder the same short brief: how many spaces now, how many later, how long cars typically sit, and how much power the charging system as a whole can draw.
Bid brief essentials
- Spaces now and later
- How long cars sit
- Total system power draw
- Minimum service per car
- Worked load-sharing example
That last figure comes from your electrical designer, not from the vendor. A spec sheet cannot tell you how much capacity your panel has.
If a design uses load sharing, ask for a worked example at light load and at full occupancy. A vendor who cannot produce one has not modeled your site, and filling every port at once on commissioning day is how you find out whether the example was honest.
Keep the support terms beside the specs
A warranty that covers parts but not labor, at a site four hours from the nearest technician, is not much of a warranty. Put the support terms in the same comparison as the electrical fields.
Support terms to pin down
- Response time commitment
- Nights and weekends difference
- Who the resident calls
- How refunds are issued
- Spare parts availability after discontinuation
- What happens if vendor stops trading
Ask for the response time commitment, whether it differs nights and weekends, who the resident calls when a session fails, and how a refund is issued. Ask how long spare parts remain available after a model is discontinued.
Get the answers written into the proposal, not described on a call. The wider list of what to ask a bidder is in multifamily bidder questions, and this page only covers the hardware.
Weight the hardware by how your building parks
A property where residents park twelve hours a night should weight cable durability and guaranteed minimum power far above peak output. A property with visitor parking has a different set of priorities entirely.
Once the hardware shortlist is real, what each option costs to build and run is the next comparison, and the one that usually reorders the list.
