PowerReader

This module is utelized to monitor the power consumption and production. Specifically it monitors the following:

• Produced power (ok)
• Grid Voltage (ok)
• Grid Frequency (ok)
• Consumed power
• Consumed power sub unit

The former three are measured by a Growatt PV inverter which communicats by RS-485 via a no-brand RS-485 board. The latter two are read by a light sensitive resister from a smart power meter.

Data streams

Base64 encoding shifted by ' '. Each data entry starts with a minor letter (a-z), were letters starting from x are reserved for testing purpuses.

Solar stream (12 bytes long with header "a") [Retired]

Name	Bit	offset	unit	max
Time	28	1690000000	s	23.1.2032
Power	15	0	100mW	3.2 kW
Frequency	11	4000	10mHz	60 Hz
Voltage	12	1000	100mV	500V

Solar stream2 (12 bytes long with header "e")

Name	Bit	offset	unit	max
Time	28	1690000000	s	23.1.2032
Power	16	0	100mW	6.5 kW
Frequency	11	4000	10mHz	60 Hz
Voltage	11	1500	100mV	350V

Diagnostic message (8 bytes long with header "b")

Name	Bit	offset	unit	max
Time	22	1690000000	64s	23.1.2032
Free Buff	5	0
Uptime	15	0	10min	228d

Power stream oben (9 bytes long with header "c")

Name	Bit	offset	unit	max
Time	28	1690000000	s	23.1.2032
Power	20	0	100mW	104 kW

Wiring

            Power Meter        Photon                  RS 485            Growatt
                              ╔═══════╗ Vcc          ╔══════════╗ Vcc
Vcc       ┌───────────────────║A0 Vin ║──┘      ┌────║ /RE  Vcc ║──┘     ╔══╗
│     5k  │  5k-500k (PM)     ║   A5  ║─────────┴────║ DE   B   ║────────║7 ║
├─────R───┴────R──── GND      ║   Tx  ║──────────────║ DI   A   ║────────║8 ║
│                             ║   Rx  ║──────────────║ R0   GND ║──┐     ╚══╝
│         ┌───────────────────║A1 GND ║──┐           ╚══════════╝ GND
│     5k  │  5k-500k (PM)     ╚═══════╝ GND
└─────R───┴────R──── GND