41 4.7. Meter Values

4.7. Meter Values

 

Charge Point    ----    Central System

MeterValues.req(connectorld, meterValue, [transactionId])

MeterValues.conf()

Figure 18. Sequence Diagram: Meter Values

 

A Charge Point MAY sample the electrical meter or other sensor/transducer hardware to provide extra information about its meter values. It is up to the Charge Point to decide when it will send meter values. This can be configured using the ChangeConfiguration.req message to data acquisition intervals and specify data to be acquired & reported.

The Charge Point SHALL send a MeterValues.req PDU for offloading meter values. The request PDU SHALL contain for each sample:

1. The id of the Connector from which samples were taken. If the connectorld is 0, it is associated with the entire Charge Point. If the connectorld is 0 and the Measurand is energy related, the sample SHOULD be taken from the main energy meter.

 

2. The transactionld of the transaction to which these values are related, if applicable. If there is no transaction in progress or if the values are taken from the main meter, then transaction id may be omitted.

 

3. One or more meterValue elements, of type MeterValue, each representing a set of one or more data values taken at a particular point in time.

Each MeterValue element contains a timestamp and a set of one or more individual sampledvalue elements, all captured at the same point in time. Each sampledValue element contains a single value datum. The nature of each sampledValue is determined by the optional measurand, context, location, unit, phase, and format fields.

 

The optional measurand field specifies the type of value being measured/reported.

The optional context field specifies the reason/event triggering the reading.

The optional location field specifies where the measurement is taken (e.g. Inlet, Outlet).

The optional phase field specifies to which phase or phases of the electric installation the value applies. The Charging Point SHALL report all phase number dependent values from the electrical meter (or grid connection when absent) point of view.

 

The phase field is not applicable to all Measurands.

Two measurands (Current.Offered and Power. Offered) are available that are strictly speaking no measured values. They indicate the maximum amount of current/power that is being offered to the EV and are intended for use in smart charging applications.

 

For individual connector phase rotation information, the Central System MAY query the Connector Phase Rotation configuration key on the Charging Point via GetConfiguration. The Charge Point SHALL report the phase rotation in respect to the grid connection. Possible values per connector are: