Connecting to your CPMS

GridOS connects to any OCPP-compliant backend over WebSocket. This guide covers the connection details and the most common failures.

Never paste live OCPP passwords, OCPI tokens, or client certificates into tickets, chat, or public issues. Rotate anything that may have been exposed and use Dashboard or your secret store for operational credentials.

Steps

1. 1

   Connection URL

   OCPP-J uses the charge point identity as the final path segment. Use wss:// (TLS) in any environment that is not local development.

   wss://your-cpms.example.com/ocpp/<charge-point-id>

2. 2

   Subprotocol negotiation

   The charger offers an OCPP version via the WebSocket Sec-WebSocket-Protocol header (for example ocpp1.6). Your CPMS must echo the selected subprotocol back, or compliant clients will close the connection.

3. 3

   Security profiles

   Match the profile your CPMS expects; a mismatch shows up as a failed handshake before any OCPP message is exchanged.

   Profile	Transport	Auth
   1	TLS	HTTP Basic
   2	TLS	HTTP Basic + server cert
   3	mTLS	Client certificate

4. 4

   Troubleshoot handshake failures

   • Immediate close after connect — usually a missing/echoed subprotocol or a rejected BootNotification
   • Connects then goes silent — check the negotiated HeartbeatInterval; the CPMS may be dropping idle sockets
   • 401 on connect — Basic auth credentials do not match the charger identity

Next steps

Once connected, follow Simulating a charger to drive a full session.

The left sidebar lists Overview, Actions, and Test cases only (not every message). Open the index pages below or use ⌘K search — hit labels include the protocol version (for example · OCPP 1.6) so same-named actions stay distinct.