What is the difference between cumulative and gauge meters in Data Fix?

The Data Fix engine applies different correction strategies depending on whether your meter is cumulative or gauge. The system auto-detects the type when you select a meter.

Cumulative meters (electricity, gas, water) count total consumption over time — their value should only go up. The Data Fix engine enables these fixes for cumulative meters:

• Negative delta correction — If a reading is lower than the previous one, the engine corrects it. A cumulative meter going from 5000 to 4800 is clearly an error.
• Gap fill strategy defaults to "forward fill" — Uses the last known reading to fill gaps, which is safest for running totals.
• Duplicates are merged by keeping the maximum value.

Gauge meters (heating, cooling, ventilation, CO₂) measure instantaneous values like temperature or power at a point in time. The engine enables these fixes instead:

• Out-of-range correction — Caps values that exceed the expected min/max for the measurement type.
• Negative value correction — Replaces negative values that should not exist (e.g., negative kWh power output).
• Gap fill strategy defaults to "linear interpolation" — Draws a straight line between the surrounding known values, which best approximates real-world gauge behavior.
• Duplicates are merged by averaging.

Smart defaults: When you select a meter in the Data Fix page, the system automatically enables the correct fix types and strategies. You can override these in the "Advanced options" section if needed.

Where to check meter type: The meter type badge appears below the meter selector — it shows "Cumulative Meter" (blue) or "Gauge Meter" (purple) with a short description.