MQTT

MQTT Topics

Only OpenDTU-OnBattery specific topics are documented here. Refer to MQTT_Topics.md for documentation of topics that are part of the upstream OpenDTU project and therefore are also part of OpenDTU-OnBattery.

Victron MPPT topics

General

Topic	R / W	Description	Value / Unit
victron/[serial]/PID	R	Product description	text
victron/[serial]/SER	R	Serial number	text
victron/[serial]/FW	R	Firmware number	int
victron/[serial]/LOAD	R	Load output state	ON / OFF
victron/[serial]/CS	R	State of operation	text e. g. "Bulk"
victron/[serial]/ERR	R	Error code	text e. g. "No error"
victron/[serial]/OR	R	Off reasen	text e. g. "Not off"
victron/[serial]/MPPT	R	Tracker operation mode	text e. g. "MPP Tracker active"
victron/[serial]/HSDS	R	Day sequence number (0...364)	int in days

Battery output

Topic	R / W	Description	Value / Unit
victron/[serial]/V	R	Voltage	Volt (V)
victron/[serial]/I	R	Current	Ampere (A)

Solar input

Topic	R / W	Description	Value / Unit
victron/[serial]/VPV	R	Voltage	Volt (V)
victron/[serial]/PPV	R	Power	Watt (W)
victron/[serial]/H19	R	Yield total (user resettable counter)	Kilo watt hours (kWh)
victron/[serial]/H20	R	Yield today	Kilo watt hours (kWh)
victron/[serial]/H21	R	Maximum power today	Watt (W)
victron/[serial]/H22	R	Yield yesterday	Kilo watt hours (kWh)
victron/[serial]/H23	R	Maximum power yesterday	Watt (W)

Pylontech battery topics

Topic	R / W	Description	Value / Unit
battery/settings/chargeVoltage	R	Voltage	Volt (V)
battery/settings/chargeCurrentLimitation	R	BMS requested max. charge current	Ampere (A)
battery/settings/dischargeCurrentLimitation	R	BMS requested max. discharge current	Ampere (A)
battery/stateOfCharge	R	State of Health	%
battery/stateOfHealth	R	State of Charge	%
battery/dataAge	R	How old the data is	Seconds
battery/voltage	R	Actual voltage	Volt (V)
battery/current	R	Actual current	Ampere (A)
battery/temperature"	R	Actual temperature	°C
battery/alarm/overCurrentDischarge	R	Alarm: High discharge current	0 / 1
battery/alarm/underTemperature	R	Alarm: Low temperature	0 / 1
battery/alarm/overTemperature	R	Alarm: High temperature	0 / 1
battery/alarm/underVoltage	R	Alarm: Low voltage	0 / 1
battery/alarm/overVoltage	R	Alarm: High voltage	0 / 1
battery/alarm/bmsInternal	R	Alarm: BMS internal	0 / 1
battery/alarm/overCurrentCharge	R
battery/warning/highCurrentDischarge	R	Warning: High discharge current	0 / 1
battery/warning/lowTemperature	R	Warning: Low temperature	0 / 1
battery/warning/highTemperature	R	Warning: High temperature	0 / 1
battery/warning/lowVoltage	R	Warning: Low voltage	0 / 1
battery/warning/highVoltage	R	Warning: High voltage	0 / 1
battery/warning/bmsInternal	R	Warning: BMS internal	0 / 1
battery/manufacturer	R	Manufacturer	String
battery/charging/chargeEnabled	R	Charge enabled flag	0 / 1
battery/charging/dischargeEnabled	R	Discharge enabled flag	0 / 1
battery/charging/chargeImmediately	R	Charge immediately flag	0 / 1

Huawei AC charger topics

Topic	R / W	Description	Value / Unit
huawei/cmd/limit_online_voltage	W	Online voltage (i.e. CAN bus connected)	Volt (V)
huawei/cmd/limit_online_current	W	Online current (i.e. CAN bus connected)	Ampere (A)
huawei/cmd/limit_offline_voltage	W	Offline voltage (i.e. CAN bus not connected)	Volt (V)
huawei/cmd/limit_offline_current	W	Offline current (i.e. CAN bus not connected)	Ampere (A)
huawei/cmd/mode	W	Controls GPIO output pin to switch slot detect	0 (off) / 1 (on) / 2 (set automatically depending on online_current value) / 3 (set automatically based on Power Meter reading )
huawei/data_age	R	How old the data is	Seconds
huawei/input_voltage	R	Input voltage	Volt (V)
huawei/input_current	R	Input current	Ampere (A)
huawei/input_power	R	Input power	Watt (W)
huawei/output_voltage	R	Output voltage	Volt (V)
huawei/output_current	R	Output current	Ampere (A)
huawei/max_output_current	R	Maximum output current (set using the online limit)	Ampere (A)
huawei/output_power	R	Output power	Watt (W)
huawei/input_temp	R	Input air temperature	°C
huawei/output_temp	R	Output air temperature	°C
huawei/efficiency	R	Efficiency	Percentage

Power Limiter topics

Topic	R / W	Description	Value
powerlimiter/cmd/mode	W	Power Limiter operation mode	see below
powerlimiter/status/mode	R	Get Power Limiter operation mode	see below

Setting any of these modes through MQTT has no effect if the Power Limiter is disabled by configuration in the web application. The Power Limiter will stay off in that case.

Three modes are implemented:

• 0 - Normal operation: The Power Limiter works as configured through the web application.
• 1 - Fully disable: The inverter is shut down and the Power Limiter stops operating, as if it was disabled in the web application.
• 2 - Unconditional Solar Passthrough: The power limit is set such that all solar power (adjusted for efficiency) is fed into the home. This is done irrespective of grid consumption and without consuming energy from the battery, which is the key difference to the regular Power Limiter Solar Passthrouh feature. Essentially, the inverter mimics the behavior of a traditional, non-smart inverter. This can be particularly useful in scenarios where solar power is better stored elsewhere, such as in an electric car.