Variables and measurement channels

A variable is a named channel on an instrument. Use an ingested variable for a value delivered by your source and a calculated variable for a value derived inside SanSignal.

Configure an ingested variable

1. Open an instrument and its Ingested Variables section.
2. Select Add ingested variable.
3. Enter the exact name used by the source.
4. Choose Decimal for numeric measurements or String for text values.
5. Add an alias, unit, and expected cadence when appropriate.
6. Save, then confirm the next reading in the instrument’s values view.

Names and value types are fixed after creation. For example, temperature_raw might be the integration’s stable name while “Ambient temperature” is the display alias. Use an alias to improve readability without changing the source mapping.

Units and cadence

Choose the unit that matches the stored value. A label alone does not convert the number; apply any required conversion upstream or in a calculated variable.

Expected cadence is entered in seconds. A channel expected every five minutes has a cadence of 300. It describes the expected reading frequency; configuring it does not schedule the field logger or create an anomaly definition. Configure missing-signal conditions separately.

Decimal and string values

Decimal variables can appear on numeric graphs and in calculations. String variables are useful for source status or text channels and can be inspected in tables. A comparison anomaly requires a decimal variable.

If a numeric source column arrives as text, correct the source payload or the FTP parser’s conversion policy. Do not assume the display will convert arbitrary text into measurements.

Viewing options

Viewing options can hide a variable from default instrument views. Hidden is a presentation setting, not a permission boundary. The graph offers a way to include hidden variables.

Decimal variables can use a custom graph scale with minimum, maximum, and interval. The maximum must exceed the minimum and the interval must be positive. Choose scales that make comparisons clear without concealing values outside the visible range.

Retire a channel

Archive an ingested variable when it should stop accepting new data. Its ingestion name remains reserved and history remains available. Active calculated variables that depend on it must first be reconfigured or archived. Restoration reuses the existing identity after parent and dependency checks.