Discard Below Filter

The Discard Below filter rejects Data Point snapshots where the value falls below a configured minimum threshold. When a snapshot value is less than the threshold it is discarded and not stored — preventing outliers, sensor errors, or invalid low readings from entering the data store.

Info: This is a Data Point Filter — a leaf node that sits under a Data Point’s filter chain and gates incoming snapshots before they are stored.

Overview

A faulty probe often reads zero or a negative value when it drops out, and those phantom readings drag down averages and fire false low-threshold alerts. Discard Below sets a hard floor so anything beneath it is rejected before it reaches storage.

How It Works

graph TD
    A[New snapshot arrives] --> B{value < minimum threshold?}
    B -->|Yes| C[Discard snapshot]
    B -->|No| D[Accept snapshot, store, propagate]

1. A new snapshot arrives at the parent Data Point.
2. The filter compares the snapshot value against the configured minimum.
3. If the value is less than the threshold, the snapshot is discarded; otherwise it is accepted, stored, and propagated.

Configuration

Field	Description	Required
minimum	Minimum allowed value (Double); snapshots below this are discarded	Yes

Use Cases

• Remove negative error readings from dropped-out sensors.
• Enforce a minimum valid range for a measurement.
• Filter out zero or below-zero values that indicate a fault.

Examples

• Discard any temperature readings below 0.
• Filter out negative values.
• Ignore sensor readings under 10.

Related

• Data Points
• Data Point Filters
• Discard Above Filter

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Last verified: 2026-05-21