# EV Charging Station

How a home EV wallbox checks the car, switches on its power and keeps charging safe, from the status lights and screen to the contactor and RCD inside\.

By quiet\-finch\-5a6debd6

Topic: Energy

[Open the interactive Jig](https://ask.jig.com/j/5lUTcpLIY2uu)

## Transcript

### 1. A charger on the garage wall

This is a home charging station for electric cars, often called a wallbox\. It hangs on the wall and gives a car a safe supply of electricity from the house\. Drag anywhere to turn the scene and look around\.

The grey box with its black glass top is modelled on the supplied picture\.

### 2. Green means ready

Two slim light bars glow on the black glass\. A quick look from across the garage tells you the charger has power and is ready\.

Light colours mean different things on different brands, so check the manual for yours\.

### 3. The colour screen

The screen shows how much power is flowing, in kilowatts \(kW\)\. It also lists three supply lines, L1, L2 and L3, with the voltage and current on each one\.

Rated 32 A means the charger can deliver up to 32 amps on each line\.

### 4. Meter and card reader

The small grey display is an energy meter\. It counts kilowatt\-hours \(kWh\), the energy delivered to the car, the way a water meter counts litres\. The RFID mark is a card reader, so only someone with the right card can start a charge\.

### 5. Start a charge

With a car plugged in, a tap of the card asks the charger to begin\. The car and the charger check each other first, and only then is the power switched on\. Tap the card and watch the screen and the light bars\.

On a three\-phase supply, a 32 A charger can deliver up to about 22 kW\.

### 6. Three cables underneath

Two thick cables and one thin cable leave the bottom of the box\. In this model the thick one with the round gland is the charging cable, ending in a Type 2 plug resting in its holster\. The other thick cable brings power from the house, and the thin one most likely carries data\.

The picture shows only the cable stubs; the plug, holster and conduit are added here\.

### 7. Inside the box

With the front cover lifted away, the hidden helpers appear\. The contactor is a heavy\-duty switch that connects the power only when the car is ready\. Beside it, a safety cut\-out called an RCD switches off in a split second if electricity leaks where it should not\.

The inside is a typical layout, not taken from the picture\.

### 8. Safe by design

The plug's pins carry no power until the car and charger agree to charge, and the power switches off before the plug can come out\. Turn the box to the right side to find the small maker's plate\.

The car's own onboard charger sets how fast it can take power, so many cars charge below the box's top speed\.