Device class locks
Homebattery continuously monitors several parameters of the system and the connected devices. By doing so, it can:
prevent unsafe operation states
prevent uneconomic operation
This is done by running checks. If a check fails, the affected device classes are locked for activity.
There might be multiple locks active at the same time.
The LEDs on the baseboard indicate whether a device class is locked or not.
Note
Some checks can only be healed through a whole system reset. This can either be done by power cycling or triggering a reset over MQTT.
Battery offline
Check fails if any battery was not successfully read within a time interval of treshold seconds.
Check heals if all batteries were successfully read within a time interval of treshold seconds.
Objective: operational safety
Explanation: Since the communication breakdown might be the sympton of a malfunctioning battery management system, any use of the battery must be assumed to be unsafe.
Locked devices:
all
Battery cell voltage low
Check fails if any cell of any connected battery has a voltage below treshold volts.
Check heals if all cell voltages rise above (treshold + hysteresis) volts.
Objective: operational safety
Explanation: Further discharging might damage the battery.
Locked devices:
inverter
Remarks: A too small value of hysteresis might cause the system to toggle between this check failing and not failing, since cell voltages change a bit when the battery current changes.
Battery cell voltage high
Check fails if any cell of any connected battery has a voltage above treshold volts.
Check heals if all cell voltages fall below (treshold - hysteresis) volts.
Objective: operational safety
Explanation: Further charging might damage the battery.
Locked devices:
charger
solar
Remarks: A too small value of hysteresis might cause the system to toggle between this check failing and not failing, since cell voltages change a bit when the battery current changes.
Battery temperature low for charging / discharging
Check fails if any cell temperature sensor of any connected battery has a temperature below treshold degrees celsius.
Check heals if all cell temperatures rise above (treshold + hysteresis) degrees celsius.
Objective: operational safety
Explanation: Charging or discharging the battery outside its safe temperature range might damage the battery.
Locked devices:
charger (for charging)
solar (for charge)
inverter (for discharging)
Remarks: There are separate checks for charge and discharge, which can be configured independently from each other.
Battery temperature high for charging / discharging
Check fails if any cell temperature sensor of any connected battery has a temperature above treshold degrees celsius.
Check heals if all cell temperatures fall below (treshold - hysteresis) degrees celsius.
Objective: operational safety
Explanation: Charging or discharging the battery outside its safe temperature range might damage the battery.
Locked devices:
charger (for charging)
solar (for charge)
inverter (for discharging)
Remarks: There are separate checks for charge and discharge, which can be configured independently from each other.
Live power consumption data lost for charging
Check fails if no live power consumption data was received within a time interval of treshold seconds.
Check heals if live power consumption data was received within a time interval of treshold seconds.
Objective: economics
Explanation: When no live consumption data is reveiced from the power provider, the increased power consumption for charging might not be billed correctly.
Locked devices:
charger
Remarks:
This check is only useful if you:
use dynamic electricity pricing
get your live consumption data from your electricity provider (e.g. tibber)
Live power consumption data lost for discharging
Check fails if no live power consumption data was received within a time interval of treshold seconds.
Check heals if live power consumption data was received within a time interval of treshold seconds.
Objective: economics
Explanation:
the netzero algorithm does not work without live consumption data
when no live consumption data is reveiced from the power provider, the decreased power consumption might not be billed correctly.
Locked devices:
inverter
Remarks:
This check is only useful if you:
use netzero algorithm
or
use dynamic electricity pricing
get your live consumption data from your electricity provider (e.g. tibber)
MQTT offline
Check fails if the connection to the MQTT broker is interrupted.
Check heals if the connection to the MQTT broker is restored.
Objective: economics
Explanation: without a MQTT connection, homebattery can not be controlled anymore.
Locked devices:
charger
inverter
Remarks: if reconnecting fails, the whole system will reset.
Startup
Check fails if any other lock is present during startup.
Check heals if no other locks are present or after 60 seconds.
Objective: operational safety
Explanation: before a connection to all devices is established, a safe operation of the system can not be guaranteed.
Locked devices:
charger
solar
inverter
Remarks: this check can not be disabled.