Why track calibration dates?
A tracker passes on whatever its sensors report. A fuel probe on an old tank table, a load sensor after axle work or a temperature probe checked against an expired thermometer still sends numbers, and those numbers end up in theft cases, overload checks and cold-chain records. A register shows which readings you can still trust.
How does the status work?
When is a calibration a pass?
Write the error left after calibration in the same unit as the tolerance: percent of the tank, percent of the reference load, or degrees Celsius. The result is Pass when the absolute error left is within the tolerance for that sensor type, and Fail otherwise. Keep the error found as well: a large error found tells you the interval is too long.
Why does the reference matter?
A calibration is only as good as the meter, weights, weighbridge or thermometer used. The log asks for the reference's certificate date and flags Reference expired when it is earlier than the calibration date. Repeat those calibrations with a valid reference.
Which changes need a new calibration?
- A new, modified or replaced fuel tank.
- A fuel probe that was cut, moved or replaced.
- Suspension or axle work under a load sensor.
- A replaced tracker that reads the sensor.
- Readings that drift from fuel receipts, weighbridge tickets or a reference thermometer.
Limits
The intervals and tolerances in the file are typical starting points, not values from a standard or from any sensor's datasheet. Where a customer, a contract or a regulator sets its own interval or certificate rules, follow their current text. The register does not perform or certify a calibration.