Introduction
Weighing balances are essential in labs for precise measurements. Understanding their types and calibration ensures reliable results.
Types of Weighing Balances
1. Mechanical Balances
- Triple-Beam Balance – Manual, low cost, but less precise.
- Torsion Balance – Uses springs, common in schools.
2. Electronic Balances
- Precision Balance – Measures up to 0.01g (used in chemistry).
- Analytical Balance – Ultra-precise (0.0001g), essential in pharmaceuticals.
How Do Electronic Balances Work?
- Electromagnetic Force Restoration (EMFR) – Converts weight into an electrical signal.
- Strain Gauge Sensors – Used in cheaper balances, less precise than EMFR.
Calibration & Maintenance
- Internal Calibration – Uses built-in weights (convenient but less accurate).
- External Calibration – Requires certified weights (more precise).
- Environmental Factors – Avoid drafts, vibrations, and temperature changes.
Common Errors & Fixes
- Drifting Readings – Caused by static or air currents (use an anti-static mat).
- Inaccurate Results – Recalibrate if moved or after long storage.
Conclusion
Proper calibration and handling ensure long-term accuracy in lab weighing.
