Load cell drift can prove to be a potential setback for measuring. It is often hard to detect if a person lacks the means to test for significant voltage changes. With that said, we know potential causes for load cell drift and how a person can identify them.
Drift can cause your load cell to not return to 0 in between weighings. That is a concern because the 0 baseline allows you to get accurate measurement each time.
What Is Load Cell Drift?
Load cell drift is when the scales in question fluctuate on weighing the same object, leading to inconsistent results. It can be hard to identify because the drift affects all of the measurements involved, making it hard to isolate. Bad load cells can be replaced, and wiring can be fixed, as long as you know where to make repairs.
The best way to identify the cause is to note the area that is causing a drift. While the load cell itself may have the problem, the cables connecting it may also create inconsistent measurements. The controller, wiring, or external machine binding may be the source of the problem as well. These can include the bearings and shafts being affected.
One way to find the weighing system aspect that is having a problem is to conduct an IT stability test using a Junction Box. The IT stability test tests the Junction Box, relevant cables, and any instruments attached to see if which of the three is causing the problem.
The Weight and Voltage tests see if the force sensors or the load cells are causing the drift. It checks the weight of each load cell and compares it to a designated baseline. This allows you to determine which instruments need replacing.
Return To Zero tests check the load cell’s mV, store it to check it against the designated calibration, and to see if the defaults are normal. The cell should return to a value of 0 when it has no weight on it. If it doesn’t, then the problem is with the cell itself.
4 Common Reasons For Load Cell Drift
1. Load Cell Damage
Damage to the load cell itself can cause drift. This can come from excessive strain, poor handling, or parts wearing out over time.
The simple solution is to check your load cells with a Return-to-Zero test, to see how often they reach defaults. Another is to conduct routine inspections and identify parts that need to be replaced. Make sure the cell’s mounting surface is solid and not nicked; it needs to be rigid, rugged, and durable.
2. How Temperature Affects Load Cells
One of the most common explanations for the drift is rapid changes in temperature. Mass increases and decreases based on the heat or coolness in a room, on a micron level. A sudden drop in temperature causes the item’s mass to decrease, and it takes a while to return to its original reading. This influx of heat often causes Load Cell drift and must be taken into consideration.
A solution for extreme temperatures is to recalibrate on a regular basis if you cannot change the warehouse environmental conditions. We recommend that in areas with different seasons, that you should schedule regular load cell recalibrations.
3. Moisture Damage to Industrial Load Cells
Moisture is another cause for the potential draft; many warehouses and outdoor areas run the risk of exposing a weighing system to excess droplets and vapor. The droplets can get into the cables, damaging them and the instruments inside the load cell. They can cause clogs and rust, which are not welcome.
Check your Junction Box and the cables for moisture when doing checks. Create waterproof environments for your load cells if possible, and do what you can to remove potential humidity.
4. Static Electricity Load Cell Drift
In addition to excess moisture being a problem, a deficiency of it can introduce static electricity to your scale. Load cells are prone to this buildup, especially if they are not properly grounded. When the static discharge becomes too high, it skews the readings in load cells and corrupts their memory.
Have a setup in place to remove static electricity when it hits a threshold. One option is to add ionizers to your work atmosphere, to reduce the amount of positive and negative ions in the air.
Make sure that your load cells have multiple grounding points to transfer the excess.
Optimize Your Weighing Systems With Arlyn Scales
Arlyn Scales has spent years honing precision and accuracy within weighing systems. Our engineers work to revolutionize load cells with updated strain gauge designs and handle a heavier load. We have recently released a new digital load cell series to provide more sensitive accuracy to our customers.
Reach out to us today to get started with customized load cells. At Arlyn Scales, we want to ensure that you can handle any industrial obstacle that affects your load cells at work. Let us ensure that your load cells can withstand drift, and you can identify the potential cause and effect.