Selecting Scale Weights for Calibration Testing

Selecting Calibration Weights

Calibrating precision digital scales, analytical balances and moisture analyzers that rely on accurate weight measurement requires periodic tests using a scale weight closely matching the maximum capacity of the instrument being tested.

Why Testing with Scale Weights is Important

Test weights can be purchased individually or in sets.
Scale weights can be purchased individually or in sets.

Daily we depend on weighing accuracy – such as visits to the deli counter in the supermarket. We want assurance that the weight shown on the scale is accurate. The U.S. Government’s Weights and Measures Division sets the guidelines.

But in research labs and in food, drug and other production facilities, weighing accuracy assumes a highly critical criterion.  This applies to weighing and measuring instruments where readout (the smallest weight difference displayed) and linearity (the ± deviation from the actual weight) are governed by GLP, ISO and other standards.

Adding to challenges, the accuracy of precision weighing and measuring instruments can be … Read the rest

How to Determine Moisture Content

What is a Moisture Analyzer?

Moisture content – the amount of moisture contained in a product – can be determined by using a moisture analyzer.  Specifications for correct moisture content span a host of industries and products.  Here you will learn how moisture analyzers are employed by researchers, QC personnel, professional associations, and government agencies to ensure products meet moisture content specs.  It includes info on how moisture analyzers work along with purchasing and operating tips.      

Why Moisture Content is Critical

According to Title 21 of the Code of Federal Regulations section n, “Safe-moisture level is a level of moisture low enough to prevent the growth of undesirable microorganisms in the finished product under the intended conditions of manufacturing, storage, and distribution.”  

Types of Moisture

While most folks think of moisture as water, moisture is anything that evaporates on heating.  Examples include fats, oils, alcohol, and solvents.

Moreover, moisture can lurk in places you … Read the rest

Moisture Analyzer for Injection Molded Plastics

Today virtually all aspects of our lives are touched by injection molded plastics.  These versatile plastic resins in a variety of formulations perform in products ranging from toothbrushes to automotive consoles to minute surgical implants.  Because the moisture content of these plastics is so critical to performance, a moisture analyzer is an essential tool to ensure materials are within specification.

What is too wet or too dry?

Ascertaining the correct moisture content for a resin depends on what is being molded and the plastic employed. For example, a polymer manufacturer may state that the product being offered has a moisture content of 0.20 percent by weight or 2,000 parts per million.  But atmospheric conditions, humidity and other factors may cause a change, especially if the product is hygroscopic or accumulates moisture on its surface due to adsorption. Similarly, storage in areas with very low relative humidity could result in lowering … Read the rest