Start a Charging Session
EV driver starts a charging session via a mobile app and monitors the session's progress in real time.
When a user initiates a charging session through the custom app by selecting Start charging, the custom backend takes action, sending a POST request to the Public API through /actions/evse/v1.0/{evseId}/start endpoint. The Public API promptly replies with a response:
{"success": true, "sessionId": X, "message": "..."}
This confirms the session's successful start and assigns it a unique sessionId. Following this, the backend receives a SessionUpdateNotification via a webhook with details indicating the session's status is pending and also providing the same sessionId. In response to this notification, the mobile app displays a preparing screen to the user, signaling the charging setup is in progress.
SessionUpdateNotification:{...,"status": "pending", "sessionId": X,..}
As the session progresses, the backend receives another SessionUpdateNotification via a webhook, but this time, the status is marked as active, reflecting that charging has now officially started. Consequently, the custom app transitions from the preparing screen to a charging screen, clearly indicating to the user that the charging process is underway.
SessionUpdateNotification: {...,"status": "active", "sessionId": X,..}
Throughout the charging session, the backend obtains SessionMeterValuesNotification updates via a webhook that contains meter reading details, including the sessionId, the amount of energy consumed (represented as a value and measured in Wh), and other related metrics.
SessionMeterValuesNotification: {..,"sessionId":X, "meterValues": {...,"value":X,"unit":"Wh",...},...}
The custom backend processes these meter updates and sends them to the custom app, prompting it to refresh and display the latest charging values, ensuring the user stays informed.
Updated 5 months ago