When load cells start to malfunction, it can prove a nuisance to the managers and operators in charge of them. That is why it’s good to identify what is causing them to go wrong, from physical damage to the wrong type or range of voltage. Our experts have some answers to these problems. With our load cell troubleshooting guide, you will learn how to check load cells for these sorts of problems, and how to identify the potential issues.
Visual Checks On Load Cells
You can see the physical signs of a load cell having problems. In fact, they are the first things that you should check before testing the voltage. Disconnect the load cell before doing this. Your safety comes first before diagnosing any problems.
The load cell body should be intact and free of any obvious damage. Even if it’s made of stainless steel, which is designed to be more durable than aluminum and waterproof, the body can wear out over time or even break in some cases. The damage that happens to the exterior can affect the strain gauges on the inside, which will in turn skew the measurements. Aluminum is more prone to mechanical damage compared to stainless steel, so the same principles apply.
You can also determine if the load cell is bending unnaturally. Since strain gauges are designed to measure resistance when an object is weighed, the cell itself should bend with the strain gauge. If that is the case, then that could be another cause. The cell body’s flatness is very important. You can make sure that the cell has not been distorted from overload or shock abuse.
Cable connections are another potential concern. He load cells have cables that connect to a power source, and the damage to them can affect the signals or power sent through, especially with the equipment being sensitive. Make sure that the cables are not ripped up, crimped, or mildly damaged. Damages to the connection will affect measuring the output.
Electrical Leakage Checks
Resistance is one of the elements to check when testing your load cell for errors. They are tied into potential electrical problems, with how the signals may become skewed or distorted. You need a multimeter tool to run some of the tests that we recommend, as well as a voltage source.
First, make sure that your power supply is stable and constant when connecting the load cell. It may simply be that you need to improve the energy source to fix any load cell issues. In addition, electrical surges can disrupt the input and output resistance, whether from lightning strikes or electrical issues. You can tell if the input or output resistance is off by 3 kΩ, or more from the specified values.
Always test your strain gauges’ resistance; they are the heart and soul of precision and accuracy. If your load cell has more than one strain gauge, then they need to be tested individually. Improper resistance could mean that your load cell is overloaded and the calibrations are off.
How electrically insulated is your load cell? Most run by sending electrical signals, and insulation resistance contributes to accuracy. It should be more than 5 Giga Ω in an ideal situation. Test the resistance and if it is below a threshold of 2 Giga Ω, then there could be a problem.
You also want to determine input and output resistance; the cell’s specification sheet will tell you which defaults are necessary to meet. A multi-meter will help with checking these parameters, and your margin of error is typically 0.1 Ω. The load cell may be bad if it surpasses the .1 Ω margin.
When not checking the resistances, take a look at the load cell’s zero balance. The load cell should reset to zero in between measurements and when it is not weighing an item. You can test this externally, using a multi-meter. Use the load cell without weighing anything on it, and divide the resulting output voltage by the input voltage. This will give you the zero balance, and you can determine if it matches within the numbers on the calibration sheet.
Evaluate Your Shock Loads With Help From Arlyn Scales
Arlyn Scales will help you determine troubleshooting your load cells and perfecting them for future operations. Our engineers revolutionized strain gauges so that they can handle weight more precisely and risk less damage. We want to ensure that you have a high-quality scale with a load cell that is ready for the task, designed with stainless steel that will last for a long time. For the highest precision requirements, you may want to consider our Ultra Precision SAW load cells.
Reach out to us today to get started, if you want to learn more information about quality digital scales. Our representatives will answer all of your questions about potentially customizing scales for your business operations. Trust our load cells to measure your industrial items, and to make your operations accurate and efficient.