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Thermometer Scale

Thermometer scale widget

The Thermometer scale is a horizontal linear gauge styled after a classic mercury thermometer, with a color-coded bar that fills from cold blue on the left to warm red on the right. Use it on environmental monitoring dashboards or greenhouse control panels where multiple temperature readings need to be compared side by side in a compact horizontal layout.

  1. Open the dashboard in edit mode. Click Add widget in the top toolbar, or click the Add new widget icon in the center of an empty dashboard.
  2. In the widget bundle selection dialog, find and click Analogue gauges.
  3. Select the Thermometer scale widget.
  4. Configure the datasource and appearance, then click Add.

All settings in this section use Basic mode — a quick-start configuration covering the essentials. For finer widget controls like title font, card style, and tooltip, switch to the Advanced tab.

Select the source of the temperature value:

  • Device — a specific device; the gauge displays the latest telemetry value from this device.
  • Entity alias — a set of entities matched by an entity alias; use this when the target device is selected dynamically at runtime.

Add exactly one data key — the telemetry key whose value the gauge will display (for example, temperature).

Controls the visual elements of the scale face.

Setting Description
Units title Toggle to show or hide the label displayed above the scale. Enter the text (default: Temperature) and set its color and font.
Units The unit string appended to the title (default: °C). Set the display text, color, and font. Click the settings icon to configure unit conversion — see Unit conversion.
Value Toggle to show or hide the numeric readout. Set the number of digits and the text color and font.
Ticks The minimum and maximum values displayed on the scale (default: −60 to 100). Set tick label color and font.
Arrow and scale default color The color of the indicator marker and the unmarked portions of the scale.
Plate color Background fill color of the gauge area.
Scale colors Toggle to enable gradient coloring on the scale tick marks. When off, the scale uses the arrow and scale default color uniformly.

Controls the filled bar that represents the current temperature level.

Setting Description
Progress bar color - start gradient The color at the cold (left/minimum) end of the bar fill gradient (default: blue).
Progress bar color - end gradient The color at the warm (right/maximum) end of the bar fill gradient (default: red).
Bar stroke color The border color of the progress bar outline.
Setting Description
Background color Solid color background for the widget card.
Show card buttons Toggle Data export and Fullscreen buttons in the widget header.
Card border radius Corner rounding in pixels.

The Thermometer scale supports the Widget header button action — a button placed in the widget header that triggers a configured action when clicked.

Gauge Shows No Data

Cause Solution
Wrong data key name Confirm the key name matches the telemetry key sent by the device. Key names are case-sensitive.
Device not sending data Open Devices → Latest telemetry and check for recent values. If empty, verify the device transport configuration and access token.
Entity alias resolves to no entities Open Entity aliases in the dashboard and verify the alias returns results.

Progress Bar Is Fully Filled or Empty Regardless of the Value

Cause Solution
Ticks range too narrow Adjust the Ticks min and max values to cover the actual temperature range reported by the device.
Wrong telemetry key selected Confirm the data key matches the key your device actually reports.

Value Shows as N/A or Stops Updating

Cause Solution
Device has stopped sending telemetry Check device connectivity and the last activity timestamp in Devices → Latest telemetry.
Wrong datasource entity selected Verify the correct device or alias is selected in the datasource configuration.