A compact, connected 22 kW EV charger

The challenge

ETAPpro is a smart EV charger for homes and businesses. It clips into a wall dock or works on its own with adapter cables. It handles load balancing, solar charging and fleet management, and it needs no extra network cable or separate load balancer.

That flexibility depends on connectivity. The charger talks to the cloud over LTE and Wi-Fi, to phones over Bluetooth Low Energy and to charging cards over NFC. When no Wi-Fi is present, it can communicate over the grid wires with HomePlug AV2 powerline communication, so no extra Ethernet cables are required. Satellite positioning (GNSS) lets the user track where each charging session happened.

All of that had to fit next to up to 22 kW of charging power in a very small housing that is completely IP67 watertight. High currents, heat and sensitive radio circuits all had to share the same few square centimetres.

A charger that is always connected is also a target. The firmware had to stay secure across every one of those interfaces for the whole life of the product.

What we did

We designed the electronics so the power stage and the radios could live together, using separate boards that fit together in 3D space while keeping assembly and testing constraints in mind.

We wrote the firmware that ties it all together: charging control, all communication links and over-the-air updates. We built cybersecurity into it from the start, so the charger complies with the latest cybersecurity requirements.

Beyond the design

The final product was verified in an external testing lab to be compliant with the applicable EV-charging and EMC standards.

We also designed the production testing. Every charger is checked before it leaves the factory, so what customers receive works the way it was designed to.

The result

ETAPpro is on the market today as EV Chargeking’s smart, competitively priced charger for homes and businesses.