When Weighing And Counting Accuracy Are Paramount Depend On An Analytical Balance

Theres a great scene in Rain Man where Raymond the autistic savant (Dustin Hoffman) knew how many toothpicks fell on the floor

. He kept saying 82. His brother Charlie (Tom Cruise) commented that there were more than 82. Raymond then says 246 total. Charlie: How many? Sallie Dibbs (Bonnie Hunt) reading from the box: 250. Charlie: Pretty close. Sallie: Theres four left in the box.

This admittedly is a simplistic introduction to the serious topic of accuracy in weights and quantities. Precision weights and counts are critical across a broad range of businesses. Examples include research labs where processes are developed to manufacture pharmaceuticals and food products. Laboratory technicians rely on an analytical balance to develop processes and procedures that later move to commercial production.

Enter the Versatile Analytical Balance

You will not find a precision analytical balance on the production floor. These weighing and measuring instruments are found in the lab and protected from vibration, air flow and temperature fluctuations that can impair accuracy especially critical for high-end models with readouts to 0.01 milligram and linearity ( from the actual load) to 0.15 milligram. So sensitive are some of these instruments that they are capable of weighing loads as low as 1 milligram. At the other end of the scale, the maximum weight for an analytical balance can be several hundred grams.

The Talented Analytical Balance

Raymonds toothpick count provides an example of what an analytical balance can do. Piece counting is done by first manually counting out the number of pieces desired for a particular process then establishing the weight of that count. The balance can be set to display either the number of pieces or their weight.

Tolerance weighing, also called check weighing, enables laboratory technicians and researchers to program in a deviation from the target weight. In some models of analytical balances pilot lamps show red when the load is below, yellow for above and green for right on the set limit. Other models emit acoustic signals. Deviations from the target weight can also be displayed as a percentage when the target is set at 100%.

When objects being weighed or counted are placed into a special container, the weight of the container (tare weight) must be accounted for. This is accomplished by setting the balance display to zero when the empty container is put on the weighing platform. Net weight is recorded when the product is placed into the container.

Keeping it Honest

The FDA and other regulators have a keen interest in the accuracy of analytical balances. Procedures apply for initial calibration and regular recalibration of these precision instruments. High-end models automatically recalibrate under certain operating conditions, while others are manually recalibrated using external weights. What all users must also remember is that an analytical balance is a delicate instrument and should not be moved without taking proper precautions to protect the weighing mechanism.

Important, too, is GLP and ISO record-keeping. This is accommodated by connecting the analytical balance to a PC and a statistical printer using, for example, an RS 232 interface.

by: Dr. Robert Sandor

POST COMMENT

70-444 questions and answers Merchant Account And Its Benefits What are HGH Boosters and How Do they Work Matt Hustons Get Him Back Forever And What Psychological Hot Buttons Are You Pushing? Snom 220 - Setting A Standard For Use And Function Motels, Fine Dining, Fun Things And Night Bars At Ocean City, Maryland: An Boy's Pamphlet Low-cost Hostels To Experience While Backpacking At Boston And Enjoying The Jam-packed Activities Th Room Darkening Window Shades Using Blackout Shades and Other Window Coverings Criminology: Crime and Its Causes The "Ins and Outs" of Short-Term Rentals Fundamentals of the Annuity Cctv Fire To The Plate And Pipe Pipe Fittings Fire Of Concern The Situation And Historical Mission Of Lining