6 Signs It’s Time to Calibrate Your Balance or Weighing Scale

Scales, balances, and other weighing devices are common across industries of all kinds. Whether working in the shop, on the factory floor, or at the loading dock, many organizations rely on consistent and accurate readings every step of the way to profits. Appropriate service and calibration are vital if you wish to guarantee that consistency and accuracy.

Calibrate Your Scale? Why Industrial Scale Calibration Is Important

The need to calibrate your scale arises from the simple fact that no weighing device stays accurate and consistent over time. With regular use, readings from scales and balances drift from their true values as the delicate components inside shift and rebalance.

In fact, the need for weighing scale calibration has been well-understood since ancient times, so every weighing device has a design that allows for calibration using the right equipment and standardized weights. Most devices will even include a manufacturer recommendation for scheduled calibration.

In general, you can gauge when the right time to calibrate a scale is by looking at how often it’s used. Weighing equipment in use for an hour each day or less may only need annual calibration. Equipment that sees more use, though, will need more frequent calibration. Any device in use for five or more hours a day will likely need monthly calibration.

There are also other occasions when service or calibration is necessary. A variety of issues, from physical impacts to voltage surges, can knock weighing devices out of calibration.

If you notice any signs of disruption, don’t wait until your next scheduled calibration. Instead, reach out to professionals to get your device back in working order straight away.

1. Scale Readings Are Inaccurate

Accuracy is the most important factor when it comes to scale calibration. If you put weight on your scale and it doesn’t read the correct weight, then you have a problem. 

Depending on the specific use of your weighing device, you may need to test accuracy weekly, daily, or multiple times per shift. Luckily, most weighing devices will have some appropriate test weight that you can use to evaluate accuracy quickly. This is a known weight that can indicate if your scale has drifted.

It’s important to note that these test weights are more so for gauging a rough idea of accuracy, though, and generally aren’t suitable for calibration themselves. Instead, the National Institute of Standards and Technology (NIST) has standards for calibration. These lay out the guidelines for proper calibration to ensure accuracy. When you work with a professional partner to handle calibration, they’ll use special standardized weights during calibration that trace back to NIST standards. 

Keep in mind that simply zeroing a scale can’t fix issues with accuracy. Test the weighing device with several known weights that cover its entire working range. You may find that only some parts of the range are noticeably inaccurate, but this is still good reason to reach out for professional calibration.

2. Scale Readings Are Inconsistent

Inconsistent readings can be another sign that you need to calibrate your scale. If you test weights and find that you manage to get the scale to show an accurate weight after a few tries, that doesn’t mean you’ve solved the problem. Variation between measurements (even if you sometimes get an accurate reading) is a sure sign that your scale needs service and calibration.

Of course, you should keep in mind that your scale may include an unimportant decimal point that can fluctuate without significant concern. Remember to use a sample within the appropriate range of the scale. Samples that are too light can imply issues even when such differences are actually inside the acceptable range of variation. 

Different weighing devices offer different levels of precision, and understanding what to expect from each model can help you know when it’s time to calibrate your scale. More serious inconsistency can arise in individual devices across subsequent measurements or between multiple scales. 

If you have multiple weighing devices of the same type, comparing measurements between them can help identify calibration issues. Taking the same product or sample and measuring it with two separate scales can indicate when an issue is present, but that won’t tell you which of the two scales is out of calibration.

3. Can’t Achieve a Zero Reading

Ensuring calibration requires testing a number of key features that your weighing device should display. Your scale needs to have proper linearity so that readings are accurate across its entire range. It needs to show consistency across multiple measurements of the same weight. It also needs to show a proper zero reading when nothing is on the scale.

Many weighing devices will feature a zeroing button, but this is not the same as setting the zero value during professional calibration. The zero button is for adjusting the weight display of the scale, slightly adding or subtracting from the actual reading to show zero.

This is a useful feature when a weighing device has some slight amount of buildup but is by no means a replacement for calibration. Many scales will also feature a tare button that is there to temporarily adjust the weight reading to zero in order to account for a container before weighing something.

When there is nothing on the scale, it should rest at zero. It should not fluctuate around zero. Fortunately, many weighing devices feature an additional indicator that shows when the scale is truly settled at zero, and this should be the case whenever it is completely unloaded.

While these minor fluctuations might not seem like a major issue, they can indicate potential issues with other readings as well. Either the span or the consistency could be off, resulting in errors. Difficulty maintaining a proper zero reading is a likely indicator that you need to calibrate your scale.

4. Visible Rust or Corrosion

The environments that organizations use weighing devices in can vary widely. Many weighing devices have to stand up to a variety of elemental hazards, but this can lead to physical damage, wear, rust, corrosion, dirt, grime, and other factors that can impact accuracy and consistency.

Each weighing device will contain a variety of mechanical and electrical parts. Rust, corrosion, and moisture can cause these parts to develop a range of issues, ultimately leading to inaccurate and inconsistent readings.

The load cells, in particular, are highly susceptible to rust, corrosion, and moisture. These are the components that convert tension or pressure into an electrical signal that indicates the weight. Other components, including the platform/deck and any mechanical intermediaries, primarily serve to transfer weight to the load cells. Rust and corrosion can affect the weight distribution of the platform or deck, too, throwing the scale out of calibration. 

Corrosion can quickly impact the readings that come from load cells. Depending on the level of damage, you may need to do more than calibrate your scale to resolve the issue. You could need to service or replace load cells to restore your scale to working order.

A simple visual inspection can help you decide when it’s time to service and calibrate your scale (or, at least, to take a closer look yourself). If you notice surface rust or corrosion, it could also be affecting parts inside the scale and causing errors.

5. Unreadable Display

woman weighing item on an industrial scale and filling papers at factory

While the weighing component is vital to a scale, its display can be just as important. Most types of weighing devices let you view readings on a display, although some may only send signals to manufacturing execution systems or other digital solutions. 

Older weighing equipment relied on physical gauges to display weight, but today, digital displays are the accepted standard. Many types of weighing equipment will feature a port connecting it to an external display, allowing you to upgrade or replace displays as needed.

While not strictly a calibration issue, any problems with your display can be just as detrimental to your workflows. You may need professional service to get the display back in working order. Before reaching out, though, you can check simple issues such as loose connections with the scale or power supply.

Working with the right partner for your scale service and calibration can ensure that weight equipment and displays are working properly together. Professionals can carry out the mechanical and electrical maintenance and repairs needed to care for all parts of your weighing systems.

6. Broken Parts or Loose Fittings

Another sign that can indicate that it’s time to service or calibrate your scale is the presence of any broken parts or loose fittings. Most weighing devices contain a variety of parts that must fit together correctly to provide accurate measurements.

When parts become loose, though, they can throw off the balance of the scale. This can cause eccentricity issues where the load distribution on the scale affects the reading. A properly calibrated scale should show the same reading no matter where the load sits on its deck or platform.

Visible broken parts can also indicate a variety of issues. A physical impact could be responsible for any cracks or other damage, and it may have affected internal components of the scale as well. Broken parts could contribute to errors, particularly if the damage affects the deck or platform.

Even seemingly inconsequential damage could have an impact. If cracks or holes develop in the body of the scale, they could allow moisture inside. This can lead to rust and corrosion of internal components and eventually affect the load cells.

Maintain accuracy and consistency by reaching out for service and calibration whenever you notice something isn’t right with your equipment. Any physical damage or loose fittings are cause for concern. 

The Benefits of Routine Weighing Scale Calibration

industrial scale with numbers on screen and green coffee beans in hopper on blurred background

Making sure to calibrate scales and other weighing devices as needed can provide a wide range of benefits. The processes that rely on these devices require a certain level of accuracy and consistency in order for organizations to avoid a variety of issues.

First, proper calibration prevents give away. Weighing devices on production lines often portion out specific weights of products for sale. Inaccurate scales can lead to giving away more of a product every time a scale weighs a certain quantity, which can add up to significant losses over time.

The scope of this problem can vary widely across different industries. You could be losing mere grams of product when measuring consumer packaging lines or tons when your truck scales aren’t properly calibrated. In any case, your organization is losing a certain percentage of potential revenue with every passing moment.

The same problem can apply in reverse if your weighing devices are under-delivering. This can lead to unhappy customers and penalties due to your contractual obligations. In some industries, regulators can get involved and impose fines and other punitive actions. Even minor deviations can have a big impact.

Depending on your industry, internal weighing devices can impact product quality as well. If your production line relies on carefully weighed recipes when making products, inaccurate weighing devices can lead to entire production runs failing to meet quality standards.

Overall, proper weighing scale calibration provides your organization with many benefits. You can do right by your customers, satisfy regulatory compliance, avoid losses due to give away and quality issues, and maintain a solid reputation for fair practices.

Professional Service and Calibration for Your Scales

The benefits of keeping your scales properly calibrated and in good working order are clear, but you need the right partner to deliver service for all of your weighing devices. American Scale provides service and calibration for practically any model in service today and can ensure that you’re in compliance with regulations and your own internal standards.Contact us today for around-the-clock service or to set up a routine calibration schedule.