How can my card work at another company's charger?

Through roaming: operators and card providers exchange card lists, prices and session records, directly or through a roaming hub, and settle in the background.

Explained in

EV charging fundamentals · Stop 03What happens after you tap your card?Follow one tap from the card reader to the operator's backend and, for another company's card, across the roaming route and back. OCPP and OCPI in action.

Roaming lets one card work in many networks. Without it, drivers would need a separate contract for every operator. With it, the card provider settles with each operator in the background.

From “Why roaming exists”, stop 03

Terms

  1. Roaming hubA platform that connects many operators and service providers, each through one connection.
  2. RoamingCharging in another company's network with your own card or app.
  1. What happens when I tap my charging card?The charger asks its operator's backend whether the card may charge. For another company's card, the backend checks it with the roaming partner or with a list of cards it received in advance.
  2. What is the difference between OCPP and OCPI?OCPP connects a charger with its own operator's backend. OCPI connects companies, so operators and card providers can exchange card lists, tariffs and session records.
  3. Why does charging involve so many companies?Three things spread the work: the grid connection, the location where people park, and contracts that work across many networks. One company can hold several roles, but the roles stay separate.
  4. Who is the CPO and who is the eMSP?The CPO operates the charger and keeps it available. The eMSP issues the card or app, sets the driver's price and sends the invoice. One company can hold both roles.