Scales and balances are both used to “weigh” items, but are they the same thing? While these names are often used interchangeably, balances and scales differ in their purposes and applications. Keep reading to learn the key differences between scales and balances and decide which instrument is right for you.
How Is a Scale Different From a Balance?
Balances and scales are weighing instruments, but the key difference lies in what they measure. A scale measures weight, while a balance measures mass.
What Is a Scale?
A scale is an instrument that measures the force exerted by gravity on an object to determine its weight. Weight can change based on the gravity of your environment.
You place the object on the scale’s platform, and the scale uses a mechanism (like load cells) to measure the force. This force is then translated into weight and displayed in units like kilograms, grams, pounds, or ounces.
What Is a Weighing Balance?
A balance is a device used for measuring the mass (the amount of matter an object has) with high precision. Mass is unaffected by gravity and will remain the same wherever in the universe you are, which makes it essential for scientific industries.
Balances work on the principle of comparing against a known mass. Think of an old two-pan balance. You put an object you know the mass of in one pan and an object of unknown mass in the other. Today’s balances no longer require manual comparison — they use a force restoration mechanism instead. Readings for a balance are usually in grams or milligrams.
Balance vs. Scale: Accuracy
When you have a quality scale or balance, you can expect a high level of accuracy. However, balances are more accurate and precise by nature. Balances use direct comparison of mass, which is less likely to be affected by external factors. Scales, on the other hand, rely on the force of gravity to determine weight, which can be impacted by factors like air currents, vibration, and non-uniform loading.
Your scale is still highly accurate, though. But being off by half an ounce when weighing a load of sheet metal is pretty insignificant, while being off by a tenth of a milligram in a pharmaceutical setting can be serious.
How Does Scale Capacity Compare to Balance Capacity?
Since balances need to be highly accurate, they have a lower capacity than most scales, usually only offering a capacity of up to a few hundred grams. Balances aren’t meant for heavy-duty industrial use, so they don’t need to hold thousands of pounds of weight.
Plus, readability is important for balances. When working with such small measurements, you need a device that can detect even the tiniest difference in mass. That’s why balances also tend to have better readability, with some offering up to five-place readability.
When to Use a Scale vs. a Balance
In most cases, a scale will be the most appropriate device for weighing. They can be used for everything from weighing a pound of apples at the grocery store to determining the net weight of an 80,000-pound semi-truck. Construction, agriculture, forestry, manufacturing, food service, healthcare, logistics, and transportation are some industries that use scales.
Balances are more specialized and frequently seen in laboratories and research facilities. Science- and lab-based industries will most likely benefit from a balance over a scale. For example, you’ll likely see them in a pharmaceutical setting for drug formulation.
Scale or Balance: Find What You Need at UniFide CST
Whether you’re interested in a scale or balance, find the weighing equipment you need at UniFide CST. We have a great selection of industrial scales and balances appropriate for a variety of industries and uses. Browse our offerings from trusted brands like Mettler Toledo and Rice Lake online and contact us today for a quote.