man with drill
A level sensor is used to measure or detect levels or amounts of fluid in pipes, containers, or other systems, both open and sealed. Fluids are usually liquids, but can be solid materials that behave like fluids, like sand or grain, for example. Level sensors are found in many different designs depending on the intended application. Sensors of this type are manufactured by many companies around the world and are typically designed for a specific application rather than general use.
Sensors to monitor levels in containers or other closed systems can take many forms. A level sensor can be as simple as a window to view the contents directly, with a printed gauge indicating the amount of material present. However, this isn’t technically a true level sensor so much as a level meter. A true sensor is something that can detect fluid level changes and communicate those changes in some way. A fuel gauge on a car is a good example of a simple pairing of level sensor and gauge.
A typical level sensor can detect even small changes in fluid levels in a vessel or other container. Most sensors of this type are connected to some type of output system in order to send notifications to a technician at a monitoring station or to sound an alarm. Level sensors are often used to detect dangerous levels of fluid buildup within a closed system, and when a certain level is reached, an alarm sounds alerting workers or technicians to the danger.
Many sensors of this type are designed to monitor conditions in places that are not easily accessible to workers, such as elevated water tanks or where conditions are hazardous. In such cases, transmission capability is a must for the sensor and can be achieved with standard wiring or wireless transmission techniques. The latest technologies allow sensors to transmit data wirelessly to monitoring systems or even mobile devices. Sensors of this type can be physically connected to an electrical network or be battery operated.
Depending on the application, level sensors can employ a wide variety of means to accomplish their tasks. Mechanical sensors generally employ a float system to detect and measure liquid levels. Some level sensors use electrodes and a very weak electrical current to measure changes in the levels of conducting liquids. Ultrasonic sensors are capable of monitoring many liquids remotely, without the need for any part of the sensor to come into contact with the liquid. Other types of level sensors include magnetic, pressure, and even gamma-ray radiation sensors that measure levels of molten metals in foundries.