Illuminance progress bar
Who it’s for
Building managers, facilities teams, and greenhouse growers ask “where does the current light level sit within our expected range?” They want a bar that fills toward a maximum so they can see at a glance how far the reading is from the upper limit.
What it does
A sensor reading 35 lx fills the bar to 35% of the 0–100 lx scale and colors it red-orange — Bright. A reading of 2 lx fills only 2% in orange — Low.
- Horizontal progress bar that fills proportionally between the configured minimum and maximum
- Color-coded fill that changes across five illuminance bands from Dark to Very Bright
- Current value label shown alongside the bar
- Shows one sensor’s data; it does not chart trends or show a delta
How to set up
Data keys
| Key | Role | Type | Description |
|---|---|---|---|
illuminance | Bar value | Timeseries | Illuminance in lx; change the key name to match your device’s telemetry key |
The widget ships with a simulated function datasource key labeled Illuminance, so it draws random values until you point the datasource at a device and rename the key.
To point it at your own device: open the dashboard in edit mode, open the widget’s Datasources, pick the entity or entity alias, and replace the function key with the key your device reports.
If the key has never reported, the bar renders empty.
Value ranges
| Range (lx) | Level | Color |
|---|---|---|
| < 1 | Dark | Dark Gray |
| 1–5 | Low | Orange |
| 5–20 | Moderate | Orange |
| 20–50 | Bright | Red-Orange |
| 50+ | Very Bright | Red |
How to customize
- To match your sensor’s range — set Tick min and Tick max to the sensor’s minimum and maximum output; a sensor rated 0–1000 lx needs Tick max raised to 1000 so the bar fills correctly.
- To use your own illuminance thresholds — edit the color ranges; adjust the five default bands to match your application’s targets.
- To hide the value label — turn off Show value in the widget settings.
- To hide the entity name subtitle or the timestamp — turn off Show subtitle or Show date.
Tips
- The default scale is 0–100 lx, suited to low-level ambient monitoring. Raise Tick max to 500, 1000, or higher if your sensor covers a broader range; otherwise readings above 100 lx will peg the bar at 100%.
- Use this bar when position-within-range matters more than trend. Add the illuminance chart card if you also need to see how the level has changed over time.
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