Load cells are at the heart of how a weighing system works. Their technology has been refined to be as precise as possible. Today’s load cells calculate non-intrusive, highly accurate load measurement data. And when they are calibrated well, their accuracy measures around 0.03 to 1%.

Load cells are found in platform scales to provide an accurate weight measurement of the objects placed onto these platforms.  As freight weight is a significant factor when it comes to road safety, truck scales are vital in protecting truck drivers, fellow vehicles, and road conditions. Keeping them effective is an operator’s or manager’s first order of business.

Unfortunately, all too frequently, load cells fail. They undergo events that may reduce their functionality because they are easily the most vulnerable part of a weighing or scale system.

Figuring out what went wrong is just as important as knowing or learning how to fix it. After all, once you know what has happened, you can hopefully mitigate the chances of it happening again in the future.

Here are a few common causes of malfunctions in load cells.

Unbalanced Zero Connection

When your load cell is not in use, it should be resting at zero.  A number of forces can cause it to be stuck above or below this default point. Most cells use strain gauge technology, which is highly accurate and has been an industry standard for over 40 years. If you notice that the cell is stuck at 10% above or below this default, it might be time to replace your faulty load cell.

 

Mechanical Damage

You could have faulty load cells due to physical damage to the machine itself. This is especially true for older parts. Look for any distortion of the cell and any surrounding mechanisms.  If you’re unsure, contact Active Scale.  We are the largest service provider of repairs, calibrations, and certifications of all truck scales, rail scales, crane scales, and weight scales in Ontario.

 

Overloading Capacity

One of the most common causes of load cell damage comes from overloading the capacity of the scale.

Scales are rated based on what their load cells can bear and going over that limit can result in severe deformation of the load cell itself. This could result in anything from making it less accurate to making it unusable altogether.

It’s really important to stick within the rated weight allowances for your load cells in your weighing system.

 

Moisture Damage

Moisture can wreak havoc on a load cell’s electronic components as well as cause corrosion that can impact the structure and integrity of the load cell body, along with the rest of the scale system.

Check often for moisture collecting in and around your scale system. This is particularly important for older systems, as moisture can more easily infiltrate a system the older the system is, due to warping and general wear-and-tear over the years.

 

Chemical Ingress

Chemicals can perform much of the same damage as water if they get into a load cell environment or container. Additionally, they can also more heavily corrode a load cell and ruin its components and overall structure.

Make sure chemicals are stored securely away from the weighing area, and make sure nothing leaks from anything being weighed, such as trucks carrying a load of chemicals or other fluids.

 

Electrical Damage

Lightning strikes and electrical power surges can severely damage a load cell and render it inoperable.

Grounding and shielding can both mitigate the risk of electrical damage to the load cell component. A properly-installed in-ground truck scale is protected from the bulk of what a lightning strike can do.

Above-ground units, however, are more vulnerable. For non-lightning-related damage, make sure the electrical connections feeding power into the weighing area are properly rated and not stretched beyond their capacity. Too much power going into an underrated area can result in a dangerous surge.

Is your load cell damaged?

There are several indicators that something may be wrong with your load cell including:

  • Zero drift
  • Not being able to calibrate on the scale
  • No reading at all when the scale is in operation
  • Readings that are inconsistent and variable
  • Not being able to reset the scale

 

Active Scale is the largest service provider of repairs, calibrations and certifications of weigh scales in Ontario. With a fleet of seven heavy test units servicing Ontario and Quebec, we have over 20 technicians available to solve your weighing problems. Our qualified technicians are capable of servicing virtually any weigh system in use and we dispatch our technicians from our service locations in Brantford, Hamilton, Markham (GTA), Orillia, and Ottawa.

Call our toll-free 24-hour emergency service line anytime at 1-800-850-8770.