P1 telemetry
What the EVSE-SC-02 reads from the DSMR/ESMR 5 smart meter P1 port, with OBIS codes, and what it needs from the port electrically. Also the fields the Matter P1 power meter exposes.
Port requirements
| Meter | DSMR 5.0 or ESMR 5.0 (Netherlands), Fluvius (Belgium). DSMR 4 and Austrian encrypted P1 are not supported. |
| Connector | RJ12, 6P6C |
| Signal | 115200 baud, 8N1, inverted TTL, data-request pin held high |
| Interval | 1 telegram per second |
| Power | Meter must supply ≥ 250 mA on pin 1. Otherwise power the SC-02 via micro-USB or use a powered splitter. |
Fields used for load balancing
| OBIS | Field | Use |
|---|---|---|
| 1-0:21.7.0 | Instantaneous active power L1 delivered (kW) | Site load per phase |
| 1-0:41.7.0 | Instantaneous active power L2 delivered (kW) | Site load per phase |
| 1-0:61.7.0 | Instantaneous active power L3 delivered (kW) | Site load per phase |
| 1-0:22.7.0 | Instantaneous active power L1 returned (kW) | Solar export per phase |
| 1-0:42.7.0 | Instantaneous active power L2 returned (kW) | Solar export per phase |
| 1-0:62.7.0 | Instantaneous active power L3 returned (kW) | Solar export per phase |
| 1-0:31.7.0 | Instantaneous current L1 (A) | Site current, integer amps on most meters |
| 1-0:51.7.0 | Instantaneous current L2 (A) | Site current |
| 1-0:71.7.0 | Instantaneous current L3 (A) | Site current |
| 1-0:32.7.0 | Instantaneous voltage L1 (V) | Per-phase voltage |
| 1-0:52.7.0 | Instantaneous voltage L2 (V) | Per-phase voltage |
| 1-0:72.7.0 | Instantaneous voltage L3 (V) | Per-phase voltage |
Because the current fields are integer amps on most meters, the site controller derives current per phase from power and voltage (P / V) and uses the meter current only as a cross-check.
Fields used for reporting
| OBIS | Field |
|---|---|
| 1-0:1.8.1, 1-0:1.8.2 | Energy delivered, tariff 1 and 2 (kWh) |
| 1-0:2.8.1, 1-0:2.8.2 | Energy returned, tariff 1 and 2 (kWh) |
| 0-0:96.14.0 | Active tariff |
| 0-0:1.0.0 | Timestamp |
| 0-0:96.1.1 | Meter serial |
What the site controller publishes
Site totals per phase go out in pwh_site_status every 5 minutes and on change; see MQTT topics. site_current_1..3 are decimal amps.
Matter P1 power meter
The same P1 parsing runs on the Matter power meter module (ESP32-C6, Thread). It exposes three Electrical Sensor endpoints with the Electrical Power Measurement cluster (0x0090): Voltage (mV), ActiveCurrent (mA) and ActivePower (mW) per phase, signed so that export is negative, updated every second.