Explanations use OCPI 2.2.1. Physical and billing-system events are authored examples.
Part of the lesson OCPI charging session lifecycle
eMSP sends a StartSession command
Technical
5 min
eMSP sends a StartSession command
The driver taps Start in the eMSP app. The eMSP sends a START_SESSION command to the CPO with the driver's token, the location and EVSE, and a response_url for the result. The CPO answers at once with ACCEPTED: it will pass the command to the charger. Nothing has started yet.
Sandbox run · OCPI 2.2.1
Run this exchange in the sandbox
EMSP
CPO
"With the Commands module, commands can be sent from the eMSP, via the CPO to a Charge Point. Most Charge Points are hooked up to the internet via a relative slow wireless connection. To prevent long blocking calls, the commands module is designed to work asynchronously. The Sender (typically eMSP) send a request to a Receiver (typically CPO), via the Receivers Commands interface. The Receiver checks if it can send the request to a Charge Point and will respond to the request with a status, indicating if the request can be sent to a Charge Point. The Receiver (typically CPO) sends the requested command (via another protocol, for example: OCPP) to a Charge Point. The Charge Point will respond if it understands the command and will try to execute the command. This response doesn't always mean that the command was executed successfully. The Receiver (typically CPO) will forward the result in a new POST request to the Senders Commands interface."OCPI 2.2.1 specification · #mod_commands_flow"|ACCEPTED |Command request accepted by the CPO."OCPI 2.2.1 specification · #mod_commands_commandresponsetype_enum
Message FlowStep 1 of 6