The IEC 61851 standard defines the general safety requirements for conductive electric vehicle charging systems: charging modes, communication between vehicle and charger, and the minimum electrical protections required.
The IEC 62196 standard, for its part, defines the physical connectors and sockets: dimensions, pin layout, and mechanical compatibility. It's the standard that guarantees a CCS2 connector made by any manufacturer will fit correctly into any vehicle compatible with that standard.
For an installer or integrator, compliance with these two standards is not optional: they form the basis of CE certification for any charger sold within the European Union, and compliance must be demonstrable in any inspection or technical audit.
When choosing a supplier, asking for IEC 61851 and IEC 62196 compliance documentation — along with CE marking — is one of the quickest ways to rule out manufacturers that fail to offer the minimum guarantees required for a professional installation.