What Happens Inside an EV Charger Every Time You Plug In

Modern EV chargers are designed to be extremely safe and smart, and the process that happens each time you plug in is more complex than most people realise. This blog breaks down the hidden steps inside a charger and explains why each part of the process matters for your vehicle and your home electrical system.

Step One: The Charger and Car Talk to Each Other

The moment you connect the cable your EV begins a short handshake with the charger. This is a communication exchange that confirms the two systems are compatible and safe to work together.

During this handshake the car sends information including:

• Battery temperature
• Battery level
• Maximum charging speed
• Whether the vehicle is ready to accept power

The charger replies by confirming the current it can safely supply based on your home wiring, your consumer unit and the condition of the charging point itself. This process ensures nothing risky happens when power starts flowing.

This quick conversation is why smart chargers installed in Cheshunt adapt so easily to different EV brands and battery types.

Step Two: The Charger Checks for Faults

Once the handshake is complete the charger runs an internal diagnostic. This is part of what makes EV charging so safe in the UK.

The charger checks for problems such as:

• Earth faults
• Water inside the connector
• Damaged cables
• Incorrect wiring at the consumer unit
• Overheating components
• Voltage instability

If anything is detected the charger refuses to start. This is why professional installation makes such a difference. At JJB Electrical we ensure all wiring, earthing and protections in your Cheshunt property meet the correct standards so your charger passes these checks every time.

Step Three: The Charger Tests Your Home Electrical Load

Before power flows the charger measures the load already being used in your home. This helps prevent tripped circuits or overheating.

Your charger looks at:

• Current appliances running
• Heating systems
• Lights
• Other heavy-draw devices
• The spare capacity available on your supply

If your home is close to its safe limit the charger will delay or reduce power. This is called load management and it protects your property while ensuring you still get a safe, consistent charge.

Step Four: Power Begins Flowing Safely

Only after all safety checks are passed does the charger activate the contactors and allow electricity to move from your home to your vehicle.

The charger continuously regulates the current to make sure:

• The cable doesn’t overheat
• Your fuse board isn’t overloaded
• Charging stays within your vehicle’s limits

This is why high-quality chargers deliver better battery health over time. They avoid unnecessary stress on the battery by adjusting power smoothly throughout the session.

Step Five: Ongoing Monitoring During Your Charge

Once charging begins the process doesn’t stop. Your charger keeps checking conditions several times per second.
It monitors:

• Temperature inside the charger
• Voltage changes in your home
• Battery temperature
• Charging curve of your vehicle
• Faults or interruptions in supply

If anything changes the charger automatically slows, pauses or adjusts power. Most drivers never realise how many safety decisions are being made every minute.

Step Six: Safe Shutdown When the Charge Finishes

When your vehicle reaches the set charge level the charger ends the session safely.

The shutdown process includes:

• Stopping power flow
• Releasing the contactors
• Cooling internal components
• Recording the charging data
• Sending a final report to your smart app (if supported)

This controlled stop prevents arcing or sparks when you unplug the cable.

Why Homeowners in Cheshunt Should Know This Process

Understanding the internal process of your EV charger helps you spot issues early, especially if:

• Your charger keeps restarting
• Charging is slower than expected
• Your vehicle stops at a lower percentage
• Your smart app shows irregular readings

In many cases the charger is detecting a fault or instability. Getting it checked early helps prevent damage to wiring, batteries and electrical equipment.

Get Your EV Charger Installed Safely in Cheshunt

If you want complete confidence that your EV charger is performing every safety step correctly, JJB Electrical provides fully compliant smart charger installations in Cheshunt.

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📞 Call JJB Electrical today 01992 276089 - Your trusted EV charger experts in Cheshunt.