EV Use Cases

This section presents a comprehensive collection of use cases tailored for the development and refinement of integration to Payter payment terminals in EV Charge Stations using either of Payter’s Cloud Payment Service (CPS) or local Payter Session Protocol (PSP) API’s.

All use cases share some fundamental similarities; A core flow that starts with the capture of card data, and ends with a charging session, and final payment, being completed. This core flow is shown below as a Start Session and an End Session

Throughout these guides the terms “Controller” and “Charge Controller” are used to universally represent the integrating party. Integrators are typically Charge Station Management Systems or Charge Station OEM’s.

Payment Receipt Data is provided in a raw format, and it is the Charge Controller’s responsibility to provide a receipt. You can find more information in Things to Consider > EV Receipts.

Use Case and the User Experience

When and why to Start and Stop sessions are fully in the domain of the controller, but there are certain standardised approaches employed in the EV Industry, which are detailed in their own dedicated pages.

Payter emphasize the handling of adverse scenarios such as declined transactions, communication losses, and system errors. The outlined use cases address such situations to enhance system reliability and user experience by detailing error handling and recovery procedures, thereby ensuring operational consistency under a variety of conditions.

Each use case provides a detailed sequence of interactions between the driver and the system, showcasing the system’s capabilities to manage success and failures, communicate effectively with the user, and secure transactional integrity.

Start Session

Different options on how to begin the process of card payment

Stop Session

How to ensure a session is ended by an authorised person and finalized promptly and accurately.

Error Scenarios

A selection of possible issues and how to handle them, when either the charge station or driver do not follow the expected paths.

Things to Consider

In addition to the provided Use Cases, there are a few key things to consider when accepting card payments as a Charge Point Operator. These are summarised below and detailed in a linked, dedicated page for each.

Things to Consider	Description
EV Receipts	Guidance on how to provide receipts to drivers, following a completed charge session.
Setting the Authorization Amount	Some best practice on ensuring that payment is taken for all dispensed goods.
Integration Approach	The Pro’s and Con’s of a local or cloud integration.
Session Management	The importance of ensuring sessions are closed in a timely fashion.
Pre-Session Checklist	Everything required before starting a charge session.
Post-Session Checklist	Everything that needs to be finalised when charging is completed.
Idle Fees	When a vehicle is parked in a charging bay but has completed charging, idle fees can encourage the bay to be released.

User Interface (UI) Options

Throughout these flows, there are references to using the terminal to provide a user interface.

This is completely optional
This is available on the Apollo terminal family only
The functionality to achieve this is documented separately, here.

Glossary of Terms

There are a number of acronyms used throughout this documentation. Some common ones are referenced below, and more payment industry specific terms are available in the Payment Industry Glossary.

Term

Description

RFID

Radio Frequency Identification

Every other kind of contactless-enabled card, including non-EMV payment cards, E-MSP cards, other closed-user group cards, and even hotel room keys.

CUG

Closed User Group

A subset of RFID cards that can be used to identify a specific user. Can be used as a membership scheme, to provide a discount, or for any other use where possession is considered important.

Payter devices read these cards, but do not generally validate or authenticate them.

UI

User Interface

Usually a touchscreen on a charger, that allows the driver to interact with the Charge Station. In some implementations, this can be as simple as printed instructions on the charger e.g. “Plug in to Start”