The fair way to compare portable chargers is by the current each one can deliver from the outlet you will use. On a NEMA 14-50 outlet, the EV-ACS4005T can supply up to 40 A, about 9.6 kW. Any factory mobile connector is likewise limited by its own current rating and the adapter fitted. Check the current printed on each unit’s label or manual, multiply by your voltage, and the higher figure charges faster, up to the limit of your car.
Key Takeaways
- Compare chargers by current on the outlet you will use.
- 40 A at 240 V is about 9.6 kW.
- The car’s onboard charger caps the speed.
- Cable length and display are practical extras, not speed factors.
The Formula That Settles It
Power in kW equals voltage times current divided by 1,000. On a 240 V supply:
| Current offered | Power at 240 V | Approx. range added per hour* |
|---|---|---|
| 12 A | 2.9 kW | 8 to 11 miles |
| 16 A | 3.8 kW | 11 to 15 miles |
| 24 A | 5.8 kW | 17 to 23 miles |
| 32 A | 7.7 kW | 23 to 31 miles |
| 40 A | 9.6 kW | 29 to 38 miles |
*Assumes 3 to 4 miles per kWh. Your car’s efficiency changes these figures.
This is why the outlet matters as much as the charger. A fair test also keeps everything else equal: the same car, the same outlet, a similar starting battery level and similar weather. Change any one of those and the comparison stops being about the charger. A unit that can deliver 40 A will still deliver less if it is set lower or plugged into a smaller circuit.
What to Compare, Point by Point
Rather than relying on claims, compare documented specifications:
- Maximum current on a 14-50 outlet: read it from each unit’s label or manual.
- Adjustable settings: the EV-ACS4005T offers 16, 24, 32 and 40 A, useful on smaller circuits.
- Cable length: 25 or 28 ft on the EV-ACS4005T. Longer cables help with awkward parking.
- Weather protection: IP66 on the EV-ACS4005T.
- Display: a status screen shows current and progress at a glance.
- Plug options: some units use interchangeable adapters; the EV-ACS4005T uses a fixed NEMA 14-50P plug.
The Car Has the Final Say
Every EV has an onboard charger that sets its maximum AC rate. If your car accepts 7.7 kW, a 9.6 kW charger will not go faster. Check the owner’s manual or what an onboard charger rating means. Charging also slows near a full battery and in cold weather.
Which Should You Choose?
If you already have a factory mobile connector and a 14-50 outlet, compare its rated current on that outlet with 40 A. If you want higher current from a single fixed plug, a longer cable, or a spare unit to keep in the car, the EV-ACS4005T is a strong option. Our guide on what a mobile connector is explains the category.
Frequently Asked Questions
Is a 40 A portable charger faster than a mobile connector?
It is faster whenever it delivers more current than the other unit on the same outlet and the car can accept it. Compare rated currents.
Can I use both on the same outlet?
Use only one at a time on a circuit. Never connect two chargers to one outlet with a splitter.
Does a longer cable slow charging?
Not noticeably. Properly rated cables are sized for their current, so 25 or 28 ft makes no practical difference.
Related Reading
- What Is a Mobile Connector?
- What Is the Fastest Portable EV Charger?
- What Does an 11kW Onboard Charger Mean?
- How Fast Does a 40 Amp EV Charger Charge?
