Posts Tagged ‘precision balances’
Tips for Analytical Balance Weighing Accuracy
Accuracy is a prime if not the prime criterion for analytical balances used in industries such as researching and compounding pharmaceuticals. Analytical balance weighing accuracy is a measure of how close the displayed weight is to the actual weight of samples on the weighing pan.
Two terms apply here. The first is readout, which is the smallest difference in weight that can be read and displayed by the unit. For an analytical balance it is typically 0.1 milligram or 0.001 g. Micro and ultra microbalances can weigh lighter samples.
Accuracy is sometimes confused with precision but it is an incorrect assumption. Precise means that results are consistent. However they may be consistently wrong, and therefore not accurate.
Instead, the second term or criterion to look for is linearity. Linearity is the maximum ± deviation of the displayed sample weight vs. the actual sample weight over the weighing range of the … Read the rest
How to Achieve Precision Weighing with an Analytical Balance
An analytical balance is a precision instrument requiring much more care and attention than industrial scales and balances used outside academic and industrial research and QC labs. Analytical balances also represent a substantial investment with prices depending on weighing range, readout, reproducibility and linearity. For these and other reasons lab personnel should understand how and how not to use these instruments, thereby maintaining equipment accuracy and extending equipment life. Here are some basic steps to follow. The balance operations manual, however, is the authority in all cases.
Setting Up an Analytical Balance
As Maria sings in “The Sound of Music” let’s start at the very beginning. Setup instructions for Kern analytical balances offered by Tovatech stress the importance of location, which ideally will be permanent.
Before unpacking the precision scale select a firm level surface remote from extreme heat, temperature fluctuations, direct sunlight, … Read the rest
GLP Compliant Precision Scale for Recipe Weighing
A sous chef exercising a bit of creativity when following a recipe for a dessert might discover a significant improvement in the final product. Or maybe not. Such creativity is to be fully avoided when compounding drugs or other products where strict control of ingredients is mandatory. A precision balance employed for the purpose of recipe weighing and record keeping is the tool of choice in applications where regulatory compliance and lab efficiency are goals.
Recipe weighing using precision scales such as the Kern PCB available from Tovatech also supports research in labs where technicians create and vary formulations while seeking to develop new or improved products.… Read the rest