Variables

A Variable is a typed, named data point. It either comes from a Device (a Device Variable) or is calculated from other Variables (a Virtual Variable). Variables back every Dashboard widget, every Alarm condition, every historical query.

Overview

A Variable has a data type (Number, String, or Boolean), an optional unit, and a logging flag that determines whether history is retained. When logging is on, every value the Variable reports is stored as a timestamped point in the time-series store.

You read Variables through Dashboards, the Platform Explorer, the API, and CSV/JSON export. You write Variables either by publishing from a Device or by defining a Virtual Variable expression.

Device Variables

Device Variables are published by a Device on a configured topic path. They typically represent:

• Sensor readings (temperature, voltage, pressure)
• Device state (running/stopped, mode)
• Diagnostic values (signal strength, error counts)
• Current configuration values

Data type and unit are fixed at configuration time. Changing them later is allowed, but downstream Dashboards and Alarms may need to be re-checked.

Virtual Variables

A Virtual Variable is computed from one or more source Variables using an expression.

To create one:

1. Open Variables.
2. Click Add Virtual Variable.
3. Set name, data type, and optional unit.
4. Write the expression and pick the source Variables it references.
5. Save.

The expression language supports:

Category	Operators / functions
Arithmetic	+, -, *, /
Math	min, max, avg, sum
Conditional	if / then / else
Time-series	timeShift, movingAverage
String	concat, substring
Boolean	and, or, not

Common patterns: aggregating across Devices, converting units, deriving thresholds (a Boolean indicator from a numeric reading), and filtering out invalid values.

Configuration

Field	Applies to	Notes
Name	both	Human-readable identifier.
Description	both	Optional.
Data Type	both	Number, String, Boolean.
Unit	numeric	Optional.
Topic Path	Device Variables	MQTT topic the Device publishes on.
Short ID	both	Optional abbreviated identifier.
Logging	both	If true, history is retained.
Scaling	numeric	Multiplier and offset applied to incoming values.
Validation	numeric	Accepted range.
Filtering	numeric	Outlier rejection.
Deadband	numeric	Only log changes exceeding the threshold.

Historical Data

When logging is on, the platform stores time-series points keyed by timestamp. Retention depends on subscription plan.

You can query at two resolutions:

• Raw — every individual value as received.
• Aggregated — bucketed by an interval (1 min, 1 hour, 1 day, etc.) with an aggregation function.

Available aggregation functions: avg, min, max, sum, count, first, last.

Read paths:

• Dashboards — for visual trend exploration.
• Platform Explorer — for interactive ad-hoc analysis.
• Reports — for scheduled or on-demand summaries.
• API — for programmatic access.
• CSV / JSON export — for downstream tools.