Calibration Standards¶
Calibration standards are reference measuring instruments used as reference standards in calibration processes. calServer v2 enables full management and traceability of these standards.
Standards Are Devices¶
In calServer a reference standard is an ordinary device in the inventory. There is no separate standards list and no "standard" flag; its calibration status follows from its own calibrations. When assigning, calServer suggests devices that have already been used as standards.
No master data for reference values
calServer does not keep reference values and measurement uncertainty of a standard as master data of their own. The measurement uncertainty of a measuring point sits on the test step or comes from MET/CAL. In calServer, "standard articles" are service catalog items for orders, not reference values.
Assignment to Calibrations¶
Standards are assigned when performing a calibration:
- Open or create a calibration
- In the Standards section, select the reference standards used
- The assignment documents the traceability of the measurement
ISO 17025 Compliance
Documenting the standards used is a requirement of DIN EN ISO/IEC 17025. calServer links the calibration to the reference standards employed and records their status on the calibration date.
Validity at the Time of Calibration¶
The standards table of a calibration answers the question a calibration certificate asks: was this standard validly calibrated when it was used? Not whether it is valid today.
| Column | Refers to |
|---|---|
| Calibrated on | Calibration date of the standard's record in force at the time |
| Valid at calibration | That record's due date, with a validity badge |
| Certificate | That record's certificate number |
| Status today | The device's current state (secondary information) |
The badge has three states:
- Valid — a valid calibration of the standard was in force on that day.
- Expired — it had already lapsed on that day.
- Not determinable — no calibration of the standard can be found for that day, or the standard carries none at all. That is a gap, not a verdict.
For assignments created before this was recorded, the state is reconstructed from the standard's calibration history and marked as such. A reconstruction can change if that history is corrected later; a state captured at assignment time cannot.
Assigning without proven traceability
If validity at the time of calibration is not proven, calServer requires a justification when assigning — it does not block the assignment. There are legitimate cases (standard undergoing recalibration, substitute equipment), and a hard refusal would only mean the certificate no longer records what was measured with. The justification is stored with the assignment and travels into the certificate dataset.
The calibration certificate prints the same values. A reprint of an old certificate therefore shows the state it was issued under, not today's.
Traceability trace: forward and backward¶
The assignment of standards to a calibration can be read in both directions. In the inventory list the row action Trace opens a dialog with a direction switch:
| Direction | Answers |
|---|---|
| Calibrated with this device | Which devices were calibrated using this device as a standard? |
| Standards of this device | Which standards were used to calibrate this device? |
The dialog opens in the forward direction. The result list shows asset number, serial number, description, manufacturer, model and the next calibration date; it follows the same visibility rules as the inventory list.
What the forward direction is for
The forward direction is the audit question after an incident: a standard stands out — returned out of tolerance, damaged, overdue. What then has to be established is which calibrations are affected, that is, which devices were measured with it. Without this direction, only a walk through the entire stock would remain.
Managing Standards¶
| Action | Description |
|---|---|
| Create | Record a new standard with article data |
| Edit | Update existing standard data |
| Upload Certificate | Store the calibration certificate of the standard |
| Delete | Remove the standard (only if not assigned) |
Validity Check
Standards with an expired calibration certificate should not be used for new calibrations. Regularly check the validity of your reference standards.