What Do You Need to Know About Installing an EV Charger at Home? Circuit 1 Explained Simply

What Do You Need to Know About Installing an EV Charger at Home? Circuit 1 Explained Simply

Charging an electric car at home isn't just about convenience — it also involves the safety and stability of the whole home's electrical system. From EV Easy Thailand's experience, we have found that almost every household asks the same question: "What do we need to prepare before installing a charger so it can be used to its full potential?"

In fact, an installed EV charger is like an energy partner that works continuously for many hours at a time, so it needs a reliable supporting system from the start. Installation isn't just about fixing equipment to a wall — it's about laying a strong electrical foundation for long-term use.

For home EV charger installation, EV Easy Thailand recommends 2 types of electrical circuit to suit each home's needs, as follows:

• Circuit 1: suitable for homes with a large electricity meter that want to charge at maximum power with full-system safety
• Circuit 2: suitable for typical homes that want to separate the charger circuit from the household supply while still meeting safety standards

In this article, we will focus on Circuit 1 first, so that homeowners who want maximum performance, durability and peace of mind every time they plug in can understand its components and installation method in detail.

Circuit 1: Maximum Safety & Power Circuit — high safety and full power

This is the setup we especially recommend for homes that want the very best in performance and durability. It suits homes with a 5/100A or 30/100A meter or larger, and is designed to support charging at the equipment's maximum power, such as 7kW - 22kW depending on the number of phases in the home's supply (1-phase, 3-phase). This shortens charging time and gives the home's electrical system real stability.

Let's look at what this circuit consists of, and why it matters.

1. Direct cable run from the main distribution board

We recommend running a dedicated cable directly from the home's main distribution board to the Wallbox charger installation point. This is like creating an express lane, so current flows directly to the charger without passing through or interfering with other circuits in the home.

Suitable conditions: this circuit suits homes with a high available power supply, or those planning to use an EV over the long term.

2. Current control (Breakers)

Strict control of current is essential in this circuit.

• Main breaker: the home's main distribution board should be sized for a high total load, possibly 80A or more, to ensure the electrical system is not overloaded even when appliances are running while the car is charging.
• Dedicated charger sub-breaker: install a separate 40A breaker just for the charger. This is the first line of protection for the charger itself.

3. Large, durable cable

To handle high, continuous power draw over long periods, we use extra-large cable of 35 sq.mm or more. Using a large cable reduces heat build-up inside the cable, lowers safety risks and adds confidence in long-term use.

4. RCD Type B — the heart of safety

In this circuit, we install a Type B residual current device (RCD) inside a dedicated shock-protection enclosure.

Why Type B? Because an EV charging system may leak direct current (DC), which a general RCD cannot detect. Type B is designed to detect both AC and DC leakage current accurately, so the installation meets Europe's highest safety standards.

Peace of mind when you choose us to design your system

Choosing Circuit 1 is a smart decision, because you get a system that is safe throughout, supports maximum charging power and is also a long-term plan for future EVs.

At EV Easy Thailand, we don't just sell EV charging equipment — we are also specialists ready to advise and carefully handle every step of installation, from assessing your meter to running the cables, so your home becomes the most complete charging space possible.

What should homes with a smaller meter do?

For homeowners with a small meter, such as 15/45A, who want an installation that meets standards but is more flexible, there's no need to worry.

In our next article, we will take an in-depth look at "Circuit 2: Standard Setup", a safe, suitable and practical option for typical homes that want to charge an EV efficiently. Look out for it next month.