MeterValue data type
MeterType
The two possible meter types are:
- S0 - Charge station
- EVSE
Unit
The following are possible units defined in OCPP.
Allowable values of the optional "unit" field of a Value element, as used in MeterValues.req and
StopTransaction.req messages. Default value of "unit" is always "Wh
| Unit | Description | Note |
|---|---|---|
| wH | Watt-hours (energy). Default. | Common |
| kWh | kiloWatt-hours (energy). | |
| varh | Var-hours (reactive energy). | |
| kvarh | kilovar-hours (reactive energy). | |
| W | Watts (power). | |
| kW | kilowatts (power). | |
| VA | VoltAmpere (apparent power). | |
| kVA | kiloVolt Ampere (apparent power). | |
| var | Vars (reactive power). | |
| A | Amperes (current). | Common |
| V | Voltage (r.m.s. AC). | Common |
| kvar | kilovars (reactive power). | |
| Celsius | Degrees (temperature). | Common |
| Fahrenheit | Degrees (temperature) | |
| K | Degrees Kelvin (temperature). | |
| Percent | Percentage |
Measurand
OCPP defines different measurands that can be passed on through meter values.
The key value in most cases is the Energy.Active.Import.Register or simply 'Energy (consumed)" as represented in the EvPortal.
| Value Description | Description | Used in GFX |
|---|---|---|
| Current.Export | Instantaneous current flow from EV | |
| Current.Import | Instantaneous current flow to EV | Yes |
| Current.Offered | Maximum current offered to EV | |
| Energy.Active.Export.Register | Energy exported by EV (Wh or kWh) | |
| Energy.Active.Import.Register | Energy imported by EV (Wh or kWh) | Yes |
| Energy.Reactive.Export.Register | Reactive energy exported by EV (varh or kvarh) | |
| Energy.Reactive.Import.Register | Reactive energy imported by EV (varh or kvarh) | |
| Energy.Active.Export.Interval | Energy exported by EV (Wh or kWh) | |
| Energy.Active.Import.Interval | Energy imported by EV (Wh or kWh) | |
| Energy.Reactive.Export.Interval | Reactive energy exported by EV. (varh or kvarh) | |
| Energy.Reactive.Import.Interval | Reactive energy imported by EV. (varh or kvarh) | |
| Frequency | Instantaneous reading of powerline frequency | Yes |
| Power.Active.Export | Instantaneous active power exported by EV. (W or KW) | |
| Power.Active.Import | Instantaneous active power imported by EV. (W or KW) | Yes |
| Power.Factor | Instantaneous power factor of total energy flow | Yes |
| Power.Offered | Maximum power offered to EV | Yes |
| Power.Reactive.Export | Instantaneous reactive power exported by EV. (var or kvar) | |
| Power.Reactive.Import | Instantaneous reactive power imported by EV. (var or kvar) | |
| RPM | Fan speed in RPM | Yes |
| SoC | State of charge of charging vehicle in percentage | Yes |
| Temperature | Temperature reading inside Charge Point. | Yes |
| Voltage | Instantaneous AC RMS supply voltage | Yes |
Context
Meter Values can be sent by the Charge Station at different moments.
Typically there are Meter Values at the beginning and end of a Transaction:
- Transaction.Begin
- Transaction.End
Meter Values can be sent based either:
- Sample.periodic - meter values are sent only during an active session
- Sample.Clock - meter values are sent every clock aligned interval, e.g. every 15mins, regardless of an ongoing transaction or not.
| Value | Description |
|---|---|
| Interruption.Begin | Value taken at start of interruption. |
| Interruption.End | Value taken when resuming after interruption. |
| Other | Value for any other situations. |
| Sample.Clock | Value taken at clock aligned interval. |
| Sample.Periodic | Value taken as periodic sample relative to start time of transaction. |
| Transaction.Begin | Value taken at end of transaction. |
| Transaction.End | Value taken at start of transaction. |
| Trigger | Value taken in response to a TriggerMessage.req |
Phase
| Value |
|---|
| L1 |
| L2 |
| L3 |
| N |
| L1N |
| L2N |
| L3N |
| L1L2 |
| L2L3 |
| L3L1 |
| None |
Filtering on phases
If a Charge Station has three phases, typically it will send 4 metervalues relating to kWh:
- L1
- L2
- L3
- none
In most cases, Users are not interested in the individual phase, but the 'total' of the Charge Station.
To select the 'total', you should filter on 'none'
Format
- Raw
- SignedData
Location
- Cable
- EV
- Inlet
- Outlet
- Body
Updated 8 months ago