Hazardous Environment Scales And Intrinsically Safe Industrial Equipment

By Author: Larry Tang
Total Articles: 512
Comment this article

Industrial manufacturing environments must always have safety as a first priority. It is simply good business practice to design a manufacturing facility so that all safety hazards are minimized as much as possible. It is also required by law and code that the many safety rules be implemented. These rules may refer to toxic fumes and materials, physical dangers on moving equipment, proper signage and lighting, and flammable and explosive materials.

Explosion and fire hazards can occur for many reasons. Any area that uses or produces a wide range of chemicals and solvents may be candidates for this type of danger. Many fuels present similar a similar hazard, as do explosive materials. Even dusty environments can be dangerous in this manner.

Different environments can be rated at different levels of hazard, depending on the severity of the danger. In the United States and certain other countries, these levels are divided into Class, Division and Group. Some standards are Class I, Class II and Class III, Division 1 or Division 2, and Groups A, B, C, D, E, F and G. There are other terms, such as nonincendive, which ...
... can further describe the hazard. Europe uses a somewhat different set of classifications, and there are similar systems in use around the world. Once a specific manufacturing facility area has received a classification, it must make sure that anything used in that area meets the hazardous specifications. This applies to anything within the area, including light fixtures, power outlets, motors, mixers, computers, and measuring devices, including industrial scales.

The best type of rating available for electronic scales that are meant to be used in hazardous locations is Intrinsically Safe. This means that the scale has been designed in such a way that it cannot cause a hazardous situation, even if a failure was to occur. These Intrinsically Safe scales are often suitable for a wide range of Classes, Divisions and Groups. Generally, this type of industrial scale will have a self contained power supply that by its design, can not supply a significant amount of energy. This may be a small battery unit that has internally connected power limiters. So even if the power outputs were shorted, there would not be enough energy to ignite a flame or explosion.

Most digital scales require more energy than the specifications will allow, so they cannot obtain a rating as an explosion proof scale. Some specially designed intrinsically safe scales, such as those produced by Arlyn Scales, need such a small amount of energy that they can meet these requirements. For example, Arlyn's intrinsically safe scales only use a single C cell battery, in a specially designed housing. This battery will power the scale for up to 40 hours of use on a single charge. The battery is then re-charged in a non-hazardous area, while an alternative battery powers the scale.

A wide variety of different types of scales have been designed to meet the hazardous requirements. The Arlyn line includes a range of bench scales, platform scales, parts counting scales, floor scales and cylinder scales. Each of these industrial scales have been rated as Intrinsically Safe.

Of course, the safety rating must meet the requirement of the facility. But the digital scale should also provide the types of features that are needed for the weighing process. Most importantly, the industrial scales should be rugged. The load cells are the devices within a scale that actually measure the weight applied. Many bench scales use load cells that are manufactured from aluminum. But these may be easily damaged when loads are dropped on the scale platform, or if the platform is hit from the side. Some high quality industrial scales, such as those provided by Arlyn Scales, use special stainless steel alloys. Load cells manufactured from this material are much less likely to be damaged. It is also often the case that a hazardous area could be an environment that has harsh fumes or chemicals. The stainless steel load cell will also survive much better in this case, providing more reliable electronic scale performance.

Another important design consideration for intrinsically safe scales are the type of digital indicator. Because it is usually important to minimize the power consumption of the industrial scale, typical LED or fluorescent types of displays are not practical. One of the best choices is a large, graphics LCD display, such as those used in the Arlyn Scales. This provides an easy to read indication of the weight along with other helpful, menu activated messages.
Arlyn Scales's goal is to provide clients with superiority in equipment and service unrivaled in the scale industry. For almost 30 years Arlyn has manufactured top of the line industrial weighing equipment with an accent on quality, accuracy, advanced technology and durability. From industrial scales to platform scales and everything in between, Arlyn Scales has it all.