Balances have evolved substantially over the years

Analytical balances are precision laboratory instruments capable of weighing and counting to extremely high degrees of accuracy.  They also represent a substantial investment.  That means technicians using an analytical balance must be familiar with proper usage procedures.  Ideally these will be incorporated into the company’s operations manual. 

Instructions for setting up and operating an analytical balance such as the Kern models available from Tovatech are shipped with the units.  We summarize here some of the more salient points, some obvious, some not so obvious. 

1. Positioning an Analytical Balance

Select a firm, level location away from environmental factors that will cause inaccuracies.  These include fluctuations in temperature and humidity, exposure to dust, drafts and electromagnetic fields, and vibrations caused, for example, by the movement of heavy equipment across the floor.  Volatile atmospheres should also be avoided as they could be ignited by the balance electronics.

Turn the unit on and let it warm up for about 4 hours so it can acclimatize itself to local gravitational influences.

2. Calibrating Analytical Balances

After the 4-hour warm up you must perform an initial calibration to “tune” the balance to the influence of gravity at that location.  Depending on the model, calibration can be done automatically, internally or externally as per the instruction manual.

Recalibration exercises should be performed on a scheduled basis or if the balance is turned off or if the balance is moved or if there is a change in the environment including temperature.

3. Protect the Scale from Liquid Ingress 

Liquids entering the weighing mechanism could render the balance useless.   First tare a container then carefully add the liquid to the container little by little while it is on the balance until the desired weight is reached.  

4.  Keep the Precision Balance Clean 

Similarly take care when cleaning the unit.  Don’t use solvents, but instead use a dry or barely damp cloth followed by a dry cloth.  Immediately remove spilled solids with a soft brush or gentle vacuuming. 

5.  Plan the Balance Weighing Exercise 

Tare the balance if you use a sample container and then gently place the sample on the weighing plate.   Do not overload the precision scale. Remove the sample as quickly as feasible after data are acquired. 

In case of problems operating the weighing program, switch the scales briefly off and on. The weighing set-up must then be reinitiated.  If that doesn’t work return the balance to the manufacturer for repair. 

Remember to keep all packaging material for possible return of the scales.  In many instances scales must be returned in their original packaging.  And never ship an analytical balance with anything, including the weighing pan, on the weighing mechanism.  This can irreversibly damage the balance, depending on the type of weighing mechanism. 

Caution:  If you open the analytical balance or fail to use it accordance with the written instructions you could invalidate the warranty. 

For help in selecting an analytical balance that matches your requirement contact the weighing and measuring professionals at Tovatech.