Precision Scale Components: The Best Load Cell for High Resolution

large-ultra-precision-scale-1For many years, high resolution was something that could only be found in a laboratory scale. Higher capacity scales could not produce the necessary accuracy and resolution that some users needed. Resolution in scales beyond 50 lbs. was average, at best; and the higher the capacity, the lower the resolution. However, here at Arlyn Scales, we have been working day in and day out to help solve this problem and we are pleased to announce that we have found a solution that uses Surface Acoustic Wave, or SAW, technology. Higher resolution and accuracy is now available for higher capacity scales with this incredible innovation. Arlyn Scales is a leader in the scale industry and has been for the past thirty years. We work hard to make sure our scales are both tough and contain cutting edge technology. We stay informed of new advances in metal alloys, electronics, and scale components like our high quality load cells. Our research and development staff constantly works at finding new ways to push the envelope for current industries that use scales, as well as emerging applications that someday will use them. We manufacture our scales in our factory located in Long Island, New York. It’s conveniently located at our company headquarters so we are able to ship factory direct to our customers. This helps them save money that distributors would normally add on to the price. We take the money we save from shipping factory direct and use it to deliver a high quality scale that our competition can’t beat even at normal retail prices. Before we talk about our load cell solution for higher accuracy and resolution, it’s important to talk about the kind of standard technology that exists for scale purchasers and users.

Strain Gauge Scales

Strain Gauge scales have been the standard of the scale industry for the past sixty years. The foundation of the scale is the strain gauge load cell. Any load that is placed on the platform is transferred to the load cell. The strain gauge load cell is precisely machined using computer controlled machining centers. The load cell uses four thin sections called flexures machined out of a thin metal, usually aluminum. The strain gauges are bonded onto the flexures and bend when the flexures bend. When they bend, the gauge’s resistance changes. The gauges are wired together in the form of a Wheatstone bridge. The bridge’s voltage output changes when the resistance of the gauges changes. The voltage is then translated into a numeric format by the Analog to Digital Converter. This corresponds to the object’s weight. The thin metal design of this load cell can create significant vulnerabilities in the scale. Dropping a load on to the platform, shock loading, or putting a load beyond the scale’s capacity on the platform, over loading, can damage the load cell causing a drift in accuracy. Once the load cell is damaged, the scale must be taken out of service for repairs. Then you are looking at time and money for repairs and loss of productivity for your business. While our strain gage load cells are manufactured from stainless steel, which makes them more durable and more accurate, it doesn’t provide the high resolution required by some businesses.

Magnetic Force Resolution (MFR) Scales

The MFR scale is a great alternative for a high resolution and precision scale, but only for low capacities. Using electromagnetic force to measure the weight on the platform, the scale has a high accuracy and resolution. However, there are some issues with the scale. First of all, the scale is vulnerable to temperature changes in the work environment as well as air currents. This can create drifts in accuracy. Additionally, from a practical perspective, the scale can only provide precision accuracy up to 25 lbs. Finally, the scale is far more expensive than is really beneficial. This scale, while good enough for some applications, cannot provide higher resolution at higher capacities. They are primarily designed for laboratory work or working with small amounts of materials.

Surface Acoustic Wave (SAW) Scales

Our internationally patented Ultra Precision scales utilize SAW technology. The SAW load cells measure displacement, as opposed to the stress and strain that the strain gauge load cells measure. Inherently better than strain gage load cells, the spring element of our SAW load cells have one transmitting and one receiving transducer placed on either side. The receiver detects the SAW wave coming from the transmitter, and after the SAW wave is passed between the transmitter and receiver, it is amplified and fed back to the transmitter. When weight is placed on the load cell, the spring element bends, which changes the frequency at which the SAW wave is passed between the two transducers. By measuring this frequency, SAW load cells can digitally determine the weight of an object, which makes them inherently more accurate, since there is no analog-to-digital conversion taking place. SAW scales are capable of weighing capacities of up to 500 pounds with resolution as fine as .0001 pounds, making them up to twenty times more accurate than their strain gage counterparts. They’re much more budget friendly than MFR scales.

Precision Customer Service

Whatever precision scale you decide to purchase from us, rest assured that our customer support staff is highly trained and very knowledgeable about our product line. Not only do they know about our scales, they also have years of experience in the scale industry and can provide practical, applicable tips. Should you find that the standard models of our precision scales do not quite meet your company’s expectations, we are more than happy to discuss the various customization options. To learn more about our Ultra Precision scales and SAW load cells, or to start the order process, call us at (800) 645-4301 or fill out the form on the Contact Us page of our site.