In almost any industry, it is very important that all weight measurements be extremely precise. However, many different conditions affect the precision of industrial scales. Precision scales must be on stable, level surfaces. They should not be exposed to water or other material which may corrode the load cell and the housing. Industrial scales should be kept at room temperature.

However, sometimes, due to the nature of the work that is being done, an industrial scale may have to be subject to undesirable conditions. For example, in the food processing industry, food must be packaged by a very specific weight. This packaging often must happen in refrigerated or freezing conditions, which affect the accuracy of any precision scale.

In industrial scales, a transducer called a strain gauge load cell detects how much weight is acting on it and then outputs an electrical signal. When an object is placed on it, the load cell stretches a certain amount proportional to the weight of the object. This stretching bends a strain gauge, which is an electrical resistor, and changes its resistance. This changes the electrical output signal. At low temperatures, the load cell will contract, which will change the electrical output of the resistor, making the computerized components of the scale believe that there is a weight on the load cell. Manufacturers of high-quality electronic scales, like Arlyn Scales, will counteract this effect by using temperature-compensating resistors.

Another component of industrial scales that is affected by low temperatures it the scale’s digital indicator. Most digital scale manufacturers use Liquid Crystal Displays (LCDs) as indicators. At low temperatures, many LCDs suffer a lost of contrast or even a complete loss of visibility. Arlyn Scales uses special low-temperature LCDs to avoid this problem. In addition, it is important to use a sealed, gasketed housing for the display to prevent moisture from reaching the electronic components.

This data recording can be done by humans. However, this opens up the possibility of human error-the data may be recorded incorrectly. Sometimes, digital scales may be connected to a computer using a standard communication protocol such as RS-232. But if the computer is not in the vicinity of the scale, this introduces the issue of running long lengths of wire which is both expensive and time-consuming.

Scale manufacturers that offer the newest technologies, like Arlyn Scales, now make electronic scales with optional built-in Universal Serial Bus (USB) ports. Standard USB thumb drives can be plugged into these ports, and weight data from the industrial scale can be recorded on these memory devices. The digital scale can be programmed to automatically load the data on its screen onto the thumb drive at pre-set intervals such as every hour, every minute, or even several times a second. Or, an operator can press a button on the control panel of the scale to record the data at that point.

Once data has been stored onto the USB thumb drive, the device can be removed from the USB port of the electronic scale and the data can be imported into a database or spreadsheet program on any computer that has a USB port. This method of copying data from industrial scale to computer is very cheap, with 4 GB thumb drives costing as little as $10.

It seems quite obvious that it is necessary to accurately measure all of the ingredients that must be mixed together to manufacture any formulation. What is not as obvious is the level of accuracy that must be attained. This, of course, is highly dependent on the material being formulated. Some types of mixtures are, by their nature, not very accurate and standard. This may be the case with agricultural products and animal feed mixtures. Others may need higher accuracy, but these levels may be easily achieved by a regular digital scale. Standard industrial scales can provide accuracy as good as 1/10 of 1%. Many chemicals, cleaning solutions, foods, and other mixtures easily fall within this range. This allows the typical bench scales to be used for smaller quantities, or floor scales, platform scales or drum scales to be used for larger batches.

But this level of accuracy is not suitable for certain special formulations. Pharmaceuticals may need greater accuracy. Another field which typically requires extremely high precision weighing is the formulation of paints. While there are no safety issues here, the mixture of pigments and other ingredients must be exceedingly precise in order to satisfy the color sensitivity of the human eye. Even very small discrepancies between two batches of paint can be instantly identified when they are displayed side by side. This type of specialty weighing calls for ultra precision scales with accuracy ranges that are ten to twenty times better than regular industrial scales.

Arlyn Scales offers a range of ultra high precision digital scales known as SAW scales, or Surface Acoustic Wave scales. There is a range of bench scales with capacities ranging from 10 lb up to 100 lb. A second range of high capacity SAW scales range in capacity from 200 lb up to 500 lb. These may be used as bench scales, or alternatively as platform scales or drum scales. Paint mixing becomes a much more accurate process with this type of weighing instrument.