In short
- Put the spread, the lowest and highest cell and the balancing state on top; the sixteen cells go in a history graph below.
- Long-term statistics on the spread show slow drift that daily graphs hide.
- One alert on the spread at the top of charge is worth more than sixteen alerts on single cells.
With MQTT discovery, Seplos Monitor creates the pack sensors in Home Assistant by itself: sensor.seplos_monitor_pack1_soc, one sensor per cell such as sensor.seplos_monitor_pack1_cell_01_voltage, the spread in sensor.seplos_monitor_pack1_cell_delta, the temperature probes and binary_sensor.seplos_monitor_pack1_balancing. With several packs on the bus, each one gets its own set.
The top row: what changed
A first card with four entities answers the questions you actually have: how full is the pack, how far apart are the cells, how warm is it, and is the balancer working right now. If those four look normal, you can stop there.
The cells, as a picture
Below, a history graph with the sixteen cell sensors over 24 hours shows the fan of lines opening at the top of charge and closing again. It is the fastest way to see one line leave the bundle. Keep the time window to a day; a week of sixteen lines is unreadable.
If you prefer bars, a simple trick works: a card per row of four cells, each with the same minimum and maximum, so a low cell stands out at a glance.
Statistics for the slow story
Home Assistant keeps long-term statistics for sensors with a state class. Add a statistics graph of the spread, showing the daily maximum over three months. That curve tells you whether the pack is settling, stable or slowly drifting, something no daily graph will show.
One good alert
An alert on each cell sends sixteen messages for one event. Use the spread instead: above 80 mV for ten minutes while the pack is above 90 %, notify once. Add a second one for a probe above 45 °C. That is enough for most home packs.
When the dashboard says something odd
A cell that dips only when the inverter draws hard, a probe that runs hot under load, a balancer that never switches on: the guide on the first weeks of a DIY pack explains what each pattern usually means and what to check first.
Common questions
How many sensors does a pack create?
One per cell plus the pack values: charge, voltage, current, spread, temperatures, balancing and alarms. Each extra pack on the bus adds its own set.
Do I need custom cards?
No. The built-in entity, history graph and statistics graph cards are enough for the layout described here.
Does the dashboard work without internet?
Yes. Seplos Monitor talks to Home Assistant over MQTT on your home network.
