Electric Vehicles charging stations (wallbox) using Domoticz

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Smart electric vehicle charging using Domoticz

In this section it's described how to charge an electric car using EVSE modules / wallbox compatible with Domoticz.

Creasol DomBusEVSE module to build an home-made smart wallbox

DomBusEVSE module to make a home-made smart wallbox to charge the electric car vehicle

Home Habit dashboard to monitor and control DomBusEVSE DIY wallbox
Home Habit dashboard to monitor and control DomBusEVSE DIY wallbox

This is an advanced solution that uses the EVSE (Electric Vehicle Supply Equipment) module DomBusEVSE made by Creasol, in Italy: it

  • detects vehicle connection and disconnection, start and stop charging
  • detects alarms from vehicle and failure in mains power supply
  • interfaces a bidirectional energy meter to know the real time import or export power from grid, and another energy meter to measure the power and energy feed to the vehicle
  • operates as stand-alone (no need for a domotic controller) or managed mode (charging current selected by the domotic controller) with the following charging mode:
    • OFF: charging disabled
    • SOLAR: use only energy from renewable plant (power from grid = 0)
    • 25%: add 25% of available power from grid (for example, having a 6kW contractual power, it set the power consumption to 1500W)
    • 50%: add 50% of power from grid
    • 75%: max 75% of power from grid
    • 100%: use all available power from grid (charge using solar power + max available power from the grid)
    • MANAGED: charging current (power) is set by domotic controller (automation script for custom charging)
  • operating in the a MANAGED mode it's possible to set the charging power to balance the power between two or more charging stations, using an external script/automation.

It's possible to write simple automations to charge the vehicle using all available power if the battery level (SoC) is below a threshold, then use only solar power: for example, if EV battery SoC is less than 60% then set EV Mode to 100%, else set EV Mode to Solar.

Video showing electric vehicle charging by Domoticz


Prerequisites and connection diagram

  1. Creasol DomBusEVSE module
  2. bidirectional energy meter, to compute the current import and export power (optional, not needed if already installed!)
  3. type-B residual current circuit breaker
  4. 2P (single phase) or 4P (3-phases) contactor to enable/disable charging
  5. optional, but recommended, energy meter to measure the charging power
  6. 32A EV cable with type-2 or type-1 plug on one side

Click to see the connection diagram to make a smart electric car charger using DomBusEVSE module!

Another wallbox working with Domoticz...

Name and description of another wallbox that works with Domoticz...

Warnings

Electric car is not a vacuum cleaner, that stay attached to the mains socket for 30 minutes!

Keep in mind that power dissipation on connectors (and cables) is computed as P=RI² where R is the connector/wire resistance, and I² is the square of charging current.

As result, when the charge current is high, the system must be checked to prevent connections and wires from overheating and burning.