Connecting a charger to an OCPP server is usually a short task, but small mistakes can cost hours: one wrong character in the charge point ID, ws instead of wss, or a blocked port. Most connection problems come from a few typical causes, and they are easy to avoid once you know them.
This step-by-step guide explains how to connect a charger to an OCPP server (CSMS). It covers the prerequisites, where to find the settings, what each field means, how to test the connection and how to fix the most common problems. At the end, you will find an example using the Üreticy URL format.
- You need four things: a working internet connection, OCPP-capable firmware, the server URL and a unique charge point ID.
- The charge point ID is normally the last part of the URL path and must match exactly, including uppercase and lowercase letters.
- Use
wss://(TLS) whenever the charger supports it, and make sure the charger clock is correct. - A successful connection shows three signs: BootNotification accepted, regular heartbeats and a correct connector status.
Prerequisites before you start
Check these points before you open the charger settings:
- Internet connection: Ethernet, Wi-Fi or a mobile SIM card. For SIM connections, check that the data plan is active and that the APN settings are correct.
- Outgoing access: the network must allow outgoing connections to the server, usually on port 443 for
wss://. The charger opens the connection, so no incoming ports are needed. - Firmware: the charger must run firmware with OCPP support. Check which version it supports (1.6J, 2.0.1 or 2.1) and update to the latest stable firmware from the manufacturer if needed.
- Connection details from your CSMS: the server URL, the protocol version and, if used, a password.
- Installer access: the login for the charger web interface, the installer app or the configuration tool.
Where the OCPP settings are located
Every manufacturer places the settings in a different place, but there are three common options:
- Web interface: you connect a laptop to the charger by cable or to its own Wi-Fi hotspot and open a local IP address in the browser.
- Installer app: a mobile app that connects to the charger by Bluetooth or Wi-Fi.
- Configuration tool: desktop software, sometimes connected by USB or a serial cable. Some manufacturers also allow configuration through their own cloud portal.
Look for menu names such as "Backend", "OCPP", "Central System" or "Network". The installation manual usually has a dedicated section.
The fields you need to fill in
| Field (common names) | What to enter | Notes |
|---|---|---|
| Central System URL, CSMS URL, OCPP server URL | The WebSocket address from your CSMS | Starts with ws:// or wss:// |
| Charge Point ID, ChargeBoxIdentity, Station ID | A unique name for this charger | Usually appended to the URL path; case-sensitive |
| Protocol version | OCPP 1.6J, 2.0.1 or 2.1 | Must match what the CSMS expects for this charger |
| Password, authorization key | The HTTP Basic authentication password | Optional; used with security profiles 1 and 2 |
| TLS certificate | Root certificate or client certificate | Needed for wss:// if the charger does not trust the server certificate by default, and for profile 3 |
How the URL and ID work together
In OCPP, the charger connects to the server URL with its charge point ID added at the end of the path. For example, with the server URL wss://csms.example.com/ocpp and the ID CP001, the charger connects to wss://csms.example.com/ocpp/CP001.
Some chargers add the ID automatically, so you enter only the base URL. Others expect the full URL including the ID. Read the manual carefully. If the ID is added twice or not at all, the CSMS will not recognize the charger.
Step-by-step: connect the charger
- Create or reserve the charger in your CSMS, or note the charge point ID you plan to use. Use a clear naming pattern, for example site code plus number.
- Open the charger settings through the web interface, app or tool.
- Set the network connection and confirm that the charger has internet access.
- Enter the server URL and charge point ID exactly as described above.
- Select the protocol version that matches your CSMS configuration.
- Enter the password and certificate if your security setup uses them.
- Check the time settings. Enable NTP if the charger supports it, and set the correct time zone.
- Save and restart the charger or the communication module.
How to test the connection
After the restart, check these signs in the CSMS and in the OCPP message logs:
- BootNotification accepted: the charger sends its vendor, model and firmware, and the CSMS responds with Accepted. A Pending or Rejected response means the charger is known but not yet approved.
- Heartbeat: heartbeats arrive at the interval set in the BootNotification response, typically every 60 to 300 seconds.
- StatusNotification: each connector reports a status, normally Available when no vehicle is connected.
- Remote command: send a TriggerMessage or change availability and check that the charger responds.
- Test session: present an RFID card, charge a vehicle for a few minutes and check that the session and meter values appear.
For background on these messages, read What is OCPP?
Common problems and how to fix them
| Symptom | Likely cause | What to do |
|---|---|---|
| Charger never appears in the CSMS | No internet, wrong URL or blocked outgoing port | Check network status on the charger; test the URL; ask IT to allow outgoing traffic on port 443 |
| Connection is rejected immediately | Wrong or unknown charge point ID | Compare the ID character by character, including case, spaces and hyphens |
Connection works with ws:// but not wss:// | Certificate not trusted or TLS not supported | Install the correct root certificate or update the firmware |
| TLS fails although the certificate is correct | Charger clock is wrong | Enable NTP or set the time manually; certificate validation depends on the date |
| Authentication error | Wrong password or wrong security profile | Re-enter the password and check the profile setting on both sides |
| Connection drops repeatedly | Weak mobile signal or unstable network | Check signal strength, antenna position and the heartbeat and ping settings |
| Charger connects but messages fail | Protocol version mismatch | Make sure the charger and the CSMS use the same OCPP version |
Example: connecting a charger to Üreticy
In Üreticy, every customer receives a personal OCPP URL in this format:
wss://ocpp.ureticy.com/URT{customer-no}/{charge-point-id}For example, if your customer number were 1001 and your charger ID were HOTEL-01, the full address would be wss://ocpp.ureticy.com/URT1001/HOTEL-01. If your charger adds the ID automatically, enter only wss://ocpp.ureticy.com/URT1001 as the base URL and HOTEL-01 as the charge point ID.
When the charger connects with an ID that is not yet in your account, it appears automatically in the dashboard as pending. You add it with one click, and the charger then shows its live status, power and energy. A typical setup takes around ten minutes. OCPP 1.6J, 2.0.1 and 2.1 chargers use the same URL format, over WS or WSS. If something does not work, the searchable OCPP message logs show exactly which messages were exchanged. More details are on the OCPP software page.
After the connection: next steps
- Give each connector a clear name and print QR code labels so drivers and technicians can identify it.
- Add RFID cards and drivers, and set which stations each driver may use.
- Set up alerts for faults, disconnections and command timeouts.
- If you use energy quotas, configure kWh limit rules per driver or vehicle. The kWh limits and smart charging page explains how they work.
Frequently asked questions
Do I need a static IP address to connect a charger to an OCPP server?
Usually not. In OCPP-J, the charger opens an outgoing WebSocket connection to the server, so the charger does not need a public or static IP address. The network only has to allow outgoing connections to the server address and port.
What is the difference between ws:// and wss://?
Both are WebSocket addresses. ws:// sends data without encryption, while wss:// encrypts the connection with TLS. Use wss:// whenever the charger supports it, because it protects card IDs, meter values and passwords.
Can I change the charge point ID later?
Technically yes, but the CSMS will treat the new ID as a new charger. Session history and settings stay with the old ID unless your software lets you migrate them. It is best to choose a clear, permanent naming pattern from the start.
Why does my charger show Pending after BootNotification?
Pending means the CSMS has received the charger but has not fully accepted it yet, for example because it is not yet assigned to an account. Approve or add the charger in the CSMS, and it will be accepted at the next boot or retry.
How do I move a charger from one OCPP server to another?
Change the server URL, and if needed the charge point ID and password, in the charger settings, then restart the charger. Export your session history from the old system first. Because OCPP is open, you do not need to replace the hardware.
Ready to connect your first charger? Get your personal OCPP URL with Üreticy OCPP software, or contact us if you need help with a specific charger model.