GeneMate GM Series Balances, Руководство по эксплуатации, Страница: 7 / 17

Good Weighing Technique
Working with precision balances requires a steady hand and an even, uninterrupted technique. Use forceps or other
suitable utensils to place the sample (and sample container) on the weigh pan as fingers are hygroscopic.
If the balance has been idle and the draft chamber doors closed for an extended period, perform a number of test
measurements before you begin weighing to allow the atmospheric conditions (temperature, RH and barometric
pressure) inside the weighing chamber to adjust to the ambient temperature outside the chamber. Rapid changes
in atmospheric conditions will have an adverse effect on the weighing result. A series of test measurements will
also help develop a smooth working rhythm. Ensure the sample and container have acclimated to the ambient
temperature of the instrument in use. Place the sample gently on the weighing pan, in the center.
Use the smallest sample container possible to reduce the influence of laminar air movement. When working with
aqueous solutions select a sample container with a small opening to minimize the effect of evaporation. Cover the
container opening when working with light volatiles.
Static electricity may have an adverse effect on weighing results such as drift and non-repeatability. When
working with samples or containers with low conductivity properties, you can optimize the performance of the
balance by:
ü Shield the Sample from the Weigh Pan (Metal Container and /or Foil)
ü Use Anti-static Device (Brush or Ionizer)
ü Increased Ambient Humidity Levels
ü Anti-static Weigh Containers
Avoid weighing magnetically charged (ferrous) materials such as ion, nickel and ion. To minimize the effects
(non-repeatability) of ferrous material:
ü Demagnetize the Sample
ü Increase the Distance of the Sample from the Weigh Pan
ü Use Below Pan Weighing (Weigh-below) Procedure
A good working knowledge of the effects from the various environmental conditions, sample matrices, container
profiles and weighing technique is paramount for high precision weighing. Preventative measures to minimize the
effects of these conditions will provide you with optimal weighing results from your balance.
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