Operation of Electronic balance
Micro, semi micro and analytical balances are measuring instruments of the highest precision. The following points will help us obtain reliable weighing results rapidly.
a. Leveling
Check the air bubble is in the center of the level and if necessary correct this by turning the leveling feet. Then calibrate the balance.
b. Turn the balance on by
pressing the control bar. The display lights up for several seconds, then
resets to 0.0000. Then calibrate the balance.
c. Place creased, small
weighing paper on the balance pan.
d. Close the sliding glass
doors. Wait for the green dot on the left to go out. This is the
stability
indicator light, indicating that the weight is stable.
e. Press the control bar to
cancel out the weight of the container or paper. The display will
again read
0.0000.
f.
Clean-up
Use
the brush provided to clean spills in the weighing chamber. Discard any
disposable tare
containers, weighing paper, or Kimwipes in the nearest
wastebasket.
Precautions
- Don't pick up tare containers with bare hands since your fingerprints add mass. Use Kimwipes or tongs to prevent this.
- Don't lean on the bench while weighing.
- Do record the mass of your container, if you will need it later.
- Do check the level indicator bubble before weighing. The two rear balance feet serve as leveling screws.
- Do not bump or place objects on the bench after zeroing the balance.
- Mass powders on paper or dishes. Handle objects with tongs, tweezers, gloves, or paper to prevent fingerprints.
- Let hot objects cool before massing.
- Mass hygroscopic materials rapidly since they will absorb water during massing.
- When making repetitive massing always use the same procedure.
- DO NOT go off and leave spilled chemicals on or around the balance! Report any spill to the instructor so that he/she may clean it up in a proper manner, re-calibrating if necessary.
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