How does a CDR settle a session?
One minute after unplugging, the operator's backend has built the record of the session: start, end, energy, time, tariff, total.
The provider will invoice the driver from it at the end of the month.
The questionHow does the record travel, and what if it turns out to be wrong?
Charging stopped at 4:15 PM; when the cable comes out twelve minutes later, the charger reports the end of the transaction with its final meter reading over OCPP.
Select each step to see what happens.
Never deleted, only credited
A is used for billing and can be seen as a kind of invoice, so does not allow it to be deleted. If a CDR turns out to be wrong, the operator sends a for it, and then a new, corrected CDR. Both sides keep the full history.
Push or pull
- Push: the operator sends each CDR to the provider as soon as it is ready.
- Pull: the provider asks the operator for new CDRs, for example once an hour.
Since version 2.2, a CDR can carry for measuring law, so the driver's invoice can be traced back to the charger's meter.
Check your understanding
3 questions. Answer all of them to complete this stop. Each answer explains itself.
What does an operator do when a CDR it already sent is wrong?
CDRs are treated like invoices and cannot be deleted; corrections run through credit CDRs.
Who creates the charge detail record of a roaming session?
The operator has the meter readings and the tariff, so it builds the CDR and sends it to the provider.
What is the pull model for CDRs?
In the pull model the provider fetches; in the push model the operator sends.
- OCPI Open Charge Point Interface: an open protocol for roaming between operators and e-mobility service providers. EV charging fundamentals, stop 03 Glossary
- CDR Charge detail record: the digital receipt of a session, with energy, duration and tariff. EV charging fundamentals, stop 05 Glossary
- Signed meter value A meter reading signed by the meter itself, so drivers and operators can check that it is authentic and unaltered. OCPP in depth, stop 05 Glossary
- Credit CDR A record that cancels a CDR already sent; OCPI does not allow CDRs to be deleted, so corrections run through credit CDRs. Glossary
- EVRoaming Foundation: OCPI 2.3.0, CDRs module: credit CDRs, push and pull model. https://github.com/ocpi/ocpi/blob/2.3.0/release/core/mod_cdrs.asciidoc. Checked 09 Oct 2026.
- EVRoaming Foundation: OCPI 2.3.0, CDRs module: credit CDRs, push and pull model. https://github.com/ocpi/ocpi/blob/2.3.0/release/core/mod_cdrs.asciidoc. Checked 09 Oct 2026.
- EVRoaming Foundation: OCPI 2.3.0, CDRs module: credit CDRs, push and pull model. https://github.com/ocpi/ocpi/blob/2.3.0/release/core/mod_cdrs.asciidoc. Checked 09 Oct 2026.
- EVRoaming Foundation: OCPI 2.3.0, introduction and background. https://github.com/ocpi/ocpi/blob/2.3.0/release/core/introduction.asciidoc. Checked 09 Oct 2026.