How to Choose the Right Sensor for Filling Applications
There are many industries using filling applications these days—whether you’re filling bags with soda syrup or prescription bottles with medication, finding the right equipment for the job is important. After all, under filling a product leads to customer dissatisfaction or failure to meet regulatory standards. Conversely, overfilling leads to lost revenue. Accuracy and reliability are key for profitability while also making sure your customers are happy with the product output. Even reducing overfill by mere grams can save your company several thousands of dollars per year.
One way to ensure that your application is efficiently and reliably filling product is to check that you have the right sensor for your particular use. There are many types of sensors that you will find on the market including mechanical float sensors, capacitive sensors, and ultrasonic sensors. Knowing what makes each sensor different and what application each is generally used for can make your selection process more streamlined. Let’s take a deep dive into a few factors that will help you determine the right sensor for your application needs.
Type of Product Measured
A factor you should consider when choosing a sensor for your filling application is the type of product you are measuring and what container the product will be housed in. An aluminum pop can is not see-through while a plastic clear one is. Containers that are not see-through may require different sensors than those that are see-through. In addition, measuring solids versus liquid products will require different equipment at times. For example, mechanical float sensors can be used for measuring fluids, but cannot be used to measure solids. Ultrasonic and radar sensors on the other hand can be used for solids and fluids.
Sensors can be placed externally or internally to the product. At times, external sensors will require accessories to be most effective while internal sensors can face their own limitations. Knowing the environment your sensor can be placed in is important to determining how effective it will be in a fill application.
Some sensors are built to withstand extreme temperatures while others are not. Often times, failing to select a sensor built for the environment it finds itself in will lower the lifespan of the sensor itself. Other times, adding accessories that can protect the sensor can make up for this factor. Knowing what temperature conditions a sensor can handle will allow you to determine the sensor right for your use.
Often, filling applications utilize weight to determine when a package is correctly filled. This is because weight measurements can be more reliable in certain applications rather than measuring for density or level as weight isn’t influenced by factors such as temperature or viscosity. As such, the type of sensor your application utilizes will in part be determined by maximum/minimum capacity of the sensor. Think of the scale you have in your bathroom. Many scales can measure a fraction of a pound. Similarly, some applications require that a product be weighed at a fraction of an ounce.
For example, if your application fills popcorn bags to 2.25 ounces, you will require a sensor that can measure a fraction of an ounce. However, if your application requires that your sensor can determine that a bag is holding 200 pounds of apples, you will not require the same weight capacity for each scenario. Load cells are often used in weighing applications due to their ease of use and accurate readings. They are adept at weighing dry goods especially. Load cells are generally utilized on a platform to accurately determine the weight of the output.
Will your application be filling many different products? This may impact which sensor your application requires. Some sensors are built to handle changing products while others are not. A capacitive sensor may be ideal in this situation as they offer more flexibility while maintaining reliability. These sensors are able to sense a variety of products such as liquids and powders and determine the fill level of the product.
Determining the right sensor for your filling application can result in thousands of dollars saved. Failure to determine the right sensor can lead to overfill problems or even a failure to reach regulatory standards. Determining the level of reliability, flexibility, filling conditions, and weight capacity of your application can lead you to the right sensor for your needs.
John Henry Foster recently acquired Sensors Incorporated and Sensors Integration. Sensors is a national leader in integration of industrial sensors, safety and machine vision with technical service and support for OEMs, system integrators and end users. Although both companies continue to operate independent of each other, both companies have strong intellectual resources and knowledge share with one another.