Zaptec Pro OCPP 1.6J (box-level) release notes

Firmware 7.5.4.0

These release notes document the first official firmware version with native OCPP 1.6J support for Zaptec Pro. On this charger model the OCPP implementation is provided by the EVerest framework (using the libocpp OCPP library). This firmware is available through an "on-demand" process where anyone can request access to test it and provide feedback. While the firmware has been tested thoroughly, there may still be undiscovered issues.

The notes describe the differences between the Zaptec Pro OCPP Native implementation and the official OCPP 1.6 specification as described by OCA with errata v4.0. Any aspect of the OCPP implementation that diverges from the OCA specification is unintentional and may be corrected in the future. Please inform Zaptec of any such divergencies.

Known issues

Error handling: the main LED turns red when an error occurs, but no corresponding error message is sent via OCPP. Error conditions are not reported as faulted StatusNotification messages. Currently under development.

Reservation indicator: when a charger is reserved, the main LED does not change color. Also currently under development.

GetDiagnostics is not implemented in this release. Diagnostics/log upload is not available.

The Zaptec Portal may occasionally show an incorrect charger state. The correct state is always reported via OCPP.

FreeCharging is not available in this release.

Plug and Charge / ISO 15118 (high-level communication) is not available in this release.

OCPP Core profile

All features and configuration keys are implemented and adhere to errata v4.0 if not otherwise specified.

The charger exposes a single connector (NumberOfConnectors = 1).

ConnectionTimeOut defaults to 30 seconds.

HeartbeatInterval defaults to 86400 seconds (24 hours).

StopTransactionOnEVSideDisconnect is set to true. UnlockConnectorOnEVSideDisconnect defaults to true.

Local authorization is enabled by default (LocalAuthorizeOffline and LocalPreAuthorize are true, AuthorizationCacheEnabled is true).

ClockAlignedDataInterval defaults to 900 seconds and MeterValueSampleInterval to 60 seconds.

OCPP Core profile limitations

Meter values are always sent as raw.

Only a limited set of measurands are supported: Energy.Active.Import.Register, Voltage, Current.Import, Current.Offered, Power.Active.Import and Temperature. The default MeterValuesSampledData set is Energy.Active.Import.Register, Voltage, Current.Import, Current.Offered.

Power.Active.Import is reported as a total value only (not per phase). Voltage and Current are reported per phase.

Per-phase measurands (Voltage, Current) are reported relative to the grid input phases (L1, L2, L3), not relative to the phase delivered to the vehicle. For example, with single-phase charging and OnePhaseChargingPhase set to 3, the energy is drawn from grid phase L3 and reported on L3, even though the charger's internal relays route it to the vehicle's L1.

ConnectorPhaseRotation defaults to 0.RST,1.RST. It can be set, but is only informative and does not affect charger behaviour.

The charger's clock is synchronized via NTP, not from the Central System. The time provided by the Central System in BootNotification.conf and Heartbeat.conf is acknowledged but not applied. The charger expects timestamps in UTC.

Some optional BootNotification.req parameters (such as meterSerialNumber and meterType) are not sent.

As described in Known issues, error conditions light the LED red but are not reported via OCPP (no faulted StatusNotification is sent).

OCPP Firmware Management profile

Firmware updates are not performed over OCPP. The charger receives and applies firmware updates through Zaptec's own update mechanism, independently of the Central System.

OCPP Firmware Management profile limitations

UpdateFirmware is not implemented in this release. Firmware updates are managed by Zaptec, not triggered by the Central System.

GetDiagnostics is not implemented in this release, so diagnostics/log upload is not available (see Known issues).

FTP and FTPS are not supported. Only HTTP and HTTPS would be available for file transfers.

OCPP Local Auth List Management profile

All required operations and configuration keys are supported.

The authorization list is enabled by default (LocalAuthListEnabled = true), allows up to 1024 entries (LocalAuthListMaxLength) and up to 255 entries in a single SendLocalList operation (SendLocalListMaxLength).

OCPP Reservation profile

All operations and configuration keys are supported.

OCPP Reservation profile limitations

The main LED does not change color when the charger is reserved (see Known issues).

OCPP Smart Charging profile

All required operations and configuration keys are supported.

Both Current (A) and Power (W) are allowed as ChargingRateUnitType (ChargingScheduleAllowedChargingRateUnit = Current,Power).

ChargeProfileMaxStackLevel is 8, MaxChargingProfilesInstalled is 24 and ChargingScheduleMaxPeriods is 32.

Switching between three-phase and single-phase charging while charging is supported through the charger's internal relays.

OCPP Remote Trigger profile

All operations are supported and adhere to errata v4.0.

OCPP security (whitepaper edition 3)

All configuration keys are supported, including SecurityProfile and AuthorizationKey.

The default SecurityProfile is 0.

SecurityEventNotification is supported. Security events are logged and reported to the Zaptec Cloud.

OCPP security (whitepaper edition 3) limitations

SecurityProfile 0 and 1 may connect via wss://, but the Central System (CS) server certificate identity is not verified. The connection is encrypted, but the CS identity is not checked. Basic authentication credentials are still sent.

SignedFirmwareStatusNotification is not supported.

SignedUpdateFirmware is not supported.

OCPP & UK Electric Vehicles (Smart Charge Points) Regulations 2021

RandomisedDelay configuration keys are available.

Zaptec OCPP Native extensions

Configuration key OnePhaseChargingPhase selects which phase the charger uses by default when a single-phase vehicle connects. It uses the charger's internal relay switching to guide power from the correct phase, providing a software-based alternative to physical phase rotation. This simplifies installation, as installers no longer need to manually rotate phases to achieve static phase balancing, and ensures compatibility with third-party backend systems.

Allowed values are 1, 2 and 3; the default is 1.

On TN grids the value maps directly to the corresponding line (1 → L1, 2 → L2, 3 → L3). On IT grids it selects a rotating line pair.

Changes only take effect when no vehicle is connected.

The setting is primarily managed via the Zaptec Cloud, where default phases are assigned automatically. It can also be updated through the Zaptec Portal. When the authentication method is set to OCPP 1.6J in the Zaptec Portal, a pop-up describing this function will also appear.

Zaptec power management

Zaptec power management is not supported in this release.