Guide9.4

Analytical balance calibration

Step	Action	Why
1. Prepare	Place on a stable, vibration-free bench; level with the bubble indicator; connect power; warm up 30–60 minutes.	Electronics need thermal and electrical stability or results drift.
2. Clean	Brush the pan, draft shield and chamber with a soft brush.	Debris adds weight and distorts the calibration.
3. Enter calibration mode	With the pan empty and doors closed, press CAL or select Menu > Calibration > Internal/External.	Objects or air currents would corrupt the baseline.
4. Zero	Wait for a stable zero, then confirm.	Establishes the true zero reference.
5. Apply span weight	Place the certified weight (e.g. 100 g) in the centre of the pan with tongs; close the doors.	Off-centre loading changes the reading; skin oils and heat change the weight’s mass.
6. Confirm	When the stable reading matches the weight (e.g. 100.0000 g), accept.	Locks in the span value.
7. Remove weight	Remove with tongs, close doors, confirm return to zero.	Confirms the balance resets correctly.
8. Save	Select Save/Store; the balance returns to weighing mode.	Stores the new calibration internally.
9. Record	Print the report and record results in the calibration log.	Documented evidence for GMP and audit.
10. Label	Attach a calibration label with the next due date.	Shows the balance is fit for use.

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