Flow Cards
Flow cards are how PELS connects to the rest of your Homey setup.
If you only build one Flow, make it Report power usage. Everything else depends on having current load data.
Required starter Flow
Report power usage
Use the Report power usage action whenever your power meter updates.
- Input is current power in watts
- This is the data PELS uses to track hourly usage, calculate available power, and decide whether devices should be limited or resumed
Without this action, the planner cannot behave correctly.
Triggers
| Card | What it does |
|---|---|
| Capacity guard: manual action needed | Fires when PELS projects that your hourly hard-cap budget will be breached at the current run rate and no more devices can be limited. |
| Operating mode changed to... | Fires when the current PELS operating mode changes to the selected mode. |
| Price level changed to... | Fires when the price level changes between Cheap, Normal, Expensive, or Unknown. |
Use Capacity guard: manual action needed for urgent notifications, not for normal daily pacing.
Conditions
| Card | What it does |
|---|---|
| Is there enough headroom? | Checks if the current available power can fit a specified extra load in kW. |
| Is there headroom for device? | Checks if current available power can fit the device's estimated draw plus a specified extra load. Useful for stepped devices. |
| Operating mode is... | Checks which mode is active. |
| Price level is... | Checks the current price bucket. |
The device-aware condition already includes built-in hysteresis after recent limiting or resume events on the same device.
Actions
| Card | What it does |
|---|---|
| Report power usage | Feeds live meter data into PELS. Required. |
| Set capacity limit | Changes the configured hard-cap limit dynamically. |
| Set operating mode | Switches between stored modes such as Home or Night. |
| Set expected power for device | Temporarily sets a device's expected draw in watts. Fails if the device already has a configured settings.load. |
| Enable capacity control for device | Turns on capacity-based control for one device. |
| Disable capacity control for device | Turns off capacity-based control for one device. |
| Set external prices (today) | Stores today's hourly prices from a Flow tag payload. |
| Set external prices (tomorrow) | Stores tomorrow's hourly prices from a Flow tag payload. |
Common automation patterns
Mode switching
Use Set operating mode from schedules or presence events to move between comfort profiles without changing every device manually.
Stepped load control
For water heaters and similar non-EV devices using the built-in stepped-load model:
- Configure the step list in the PELS device settings.
- Use Desired stepped load changed for [device] to map PELS intent to vendor actions.
- Report the resulting step back through one of the stepped-load feedback cards.
The full worked example lives in Wire a stepped load device.
For EV chargers, prefer the EV charger control mode and wire the EV charger current (A) tag directly to the charger app's available-current action. See Configure an EV Charger. Zaptec-specific notes live in Configure a Zaptec EV Charger.
Price feed import
If you use an external price provider:
- Send the full-day JSON for today to Set external prices (today).
- Send tomorrow's full-day JSON to Set external prices (tomorrow).
- Let PELS use whichever price window is currently available.
Units to keep straight
- Available-power checks use kW
- Expected power overrides use W
- Hourly and daily budget values use kWh
Mixing these units is the most common Flow mistake.