How to Select the Right Weighing Product
A Tale of Two Balances Improving Your Balance Choice
According to Tom Delano, Business Development Manager, Adam Equipment, many manufacturers, laboratory, and industrial professionals think they have the right balance, yet may not have selected the best option to meet the measuring results they need.
“Consider the type of balance for your application, including readability and capacity; look at additional features that could offer efficiencies; and then determine how your choice fits into your budget, “said Delano.
In order to begin the selection process, keep in mind the two primary types of balances:
- Analytical balances are typically top-of-the-line. The analytical balance displays a result of at least four decimal points (for example, 0.0001 grams or 0.1 milligrams). This point display is termed the readability of the balance. The analytical balances offer superior readability. Their capacity (maximum weight) is typically up to 250 grams.
The most common analytical balances display four to five decimal point results and are used to weigh materials—chemicals and drugs, usually in powdered, liquid, or solid form.
In addition to analytical balances, micro balances display results up to six decimal points for applications that require extremely precise measurements.
- Precision balances or precision top-loaders typically display results from three to one decimal places (0.001 grams up to 0.1 gram)—meaning their readability is reduced when compared to analytical balances. Yet, precision balances accommodate higher capacities—up to several kilograms.
Some precision balances are portable and operate on batteries, providing a flexible option for field activities or similar applications. The portable precision balances are sometimes less expensive, with one or two decimal point readabilities.
In narrowing your options, follow the sequence below to land on a choice that suits your overall requirements.
1) Know the readability of your balance. Consider how precise of a measurement you need to record—and get a balance that offers an additional decimal point of readability.
“Choose an instrument that gives you a better result than necessary,” suggested Delano. “If you regularly need results at 0.001 gram or 0.005 gram, select a four place balance. Start with what kind of precision you need, then purchase the balance that has better readability so that you are not limiting yourself.”
2) Look at capacity, or maximum weight allowance. Think about the type of measuring container you will be using, along with the material to be measured.
“If you are regularly measuring 50 grams, you should focus on 100-gram capacity balances,” said Delano. “On an ongoing basis, you should be weighing in the middle of the balance’s capacity range so you avoid overloading.”
3) Consider features and options:
Features are included in the product:
- Weighing platform: Make sure the size and shape is suitable for your application.
- Computer interface: Nearly all analytical and precision balances include software. Does the interface (USB; RS-232) work with your equipment? Is the keypad and display designed for optimal use? For example, some display screens are extra large for easy viewing, perhaps from across a laboratory. If all else is equal, this may be a compelling feature.
Options are enhancements or accessories that typically involve an added cost:
- Dynamic weighing or animal weighing: This feature takes into account an animal’s movement while on the weighing platform. It records several readings within a matter of seconds and provides an average of these readings for increased accuracy.
4) Review your budget. Critical functionality, such as appropriate readability, may determine the type of balance to select, but some options may fall into the “nice to have” category if they won’t yield significant time savings.
- Specific gravity or density measurement kit. This is a common measurement for quality assurance labs to identify the quality of a product. The kit contains the necessary components to easily weigh samples in air and submerged in liquid. It will also include a thermometer and, often times, a known volume sinker used to determine the specific gravity of liquids.
Materials manufacturers, among others, use this information to determine if air is trapped in their material, creating low specific gravity. Makers of synthetic foam need similar data to indicate if too much or too little air is captured in their product. Some balances include software that guides the user through the test steps and calculates the specific gravity or density measurement automatically.
“While convenient, this option may also increase efficiency if the specific gravity or density measurement is calculated regularly,” said Delano.
“The specific gravity and density measurement kit can add as much as 20 to 30% more to the cost of your balance,” explained Delano. “This cost may be well worth it for manufacturers or other professionals consistently using this measurement. For basic laboratory applications, it may not be necessary.”