Why use OCPI?
Using OCPI brings many benefits to a CPO, but there are some minor drawbacks. As seen in the previous page, Payter have developed logic that handles the customer interaction. This interaction assumes there is only one HMI, but does not rely on this. As a result, once the requisite Module requirements are implemented, and the Payter and CPO platforms are connected, the solution should work consistently across a wide variety of charger hardware. This logic is fixed however; There is no scope to customise the user journey or the user interface.
Feature Comparison
This table shows the differences between an OCPI integration and a CPS integration.
| Feature | OCPI | CPS |
|---|---|---|
| Customizable UI | ❌ | ✅ |
| RFID Support | ❌ | ✅ |
| Reliant on Online Connectivity | ✅ | ✅ |
| User Journey Logic | Already Done ✅ | Needs to be defined and coded ❌ |
| Reliant on Third Party Documentation | ✅ | ❌ |
Comparison Details
User Interface Summary
The above is an excerpt from a transaction flow diagram, which Payter will give OCPI integrators access to. That flow diagram shows the entire customer journey in a logical flow, detailing how and why each screen will progress or timeout.
The flow, color scheme and order of these screens is fixed. CPO's who wish to leverage OCPI will have the same look and feel on their terminal as every other user of Payter's OCPI solution.
RFID Support
Whilst the Payter terminal can read a large array of RFID/eMSP cards, there is not currently support for this process via a Payment Terminal in the current versions of the OCPI standard. This functionality is expected in version 3.0 of the OCPI specification, and Payter will look to add this as soon as possible est. H2 2026.
Online Connectivity Reliance
In CPS the Payter terminal must be online to receive commands. OCPI uses the CPS interface, so this requirement continues. CPO ↔️ Charger interaction requires online connectivity however, so this is not considered to be a significant limitation.
Whilst the Payter terminal can connect to cellular networks using it's onboard modem and SIM, it can be useful to have it share the Charger connectivity. As both solutions are totally dependent on a connection, this typically means a simpler solution to troubleshoot in the event of a communication issue.
User Journey Logic
Payter have existing logic in place that a CPS integrator needs to define and implement themselves. This can be a positive, but usually requires more development effort than OCPI integration alone.
Third Party Documentation Reliance
Payter are completely reliant on the CPO following and implementing the OCPI specification correctly. Whilst comprehensive, this specification can be challenging to follow. Payter will seek to provide clarity where possible, but in reality much of the integration advice provided is likely to be a reference to the specification particulars for the piece of data being sought.