Understanding Sensor Output Signals

Have you ever wondered why there are a multitude of sensor output signals that can be configured on pressure, temperature, humidity, or gas sensing instrumentation used in process or HVAC applications? Most of these offerings were originally set up to allow sensor manufacturers to better align with the inputs offered by manufacturers of programmable logic controllers (PLCs) and direct digital controllers (DDCs), which are used for controlling processes for both automation and HVAC control.

I’d like to focus on two of the most commonly used output signals and zero in on the advantages and/ or disadvantages these output signals offer. Two of the most commonly used output signals include analog current, typically 4 to 20mA, and analog voltage, typically 0-10V. Continue reading “Understanding Sensor Output Signals”

Thermal Dispersion Flow Switches

Thermal Dispersion Flow Switch, Series TDFS2

Dwyer Instruments, Inc. offers several flow measuring products that use a thermal sensing element.

Thermal dispersion flow sensors use a temperature element that is heated up beyond the media temperature. Based on calorimetry, the flow moving past the sensor will have a cooling effect that is directly proportional to the flow velocity. The heat is convected from the heated probe surface to the boundary layer of the fluid flowing over the heated surface. Continue reading “Thermal Dispersion Flow Switches”

RTD Temperature Sensors

Temperature Sensors

Dwyer Instruments, Inc. offers a wide variety of temperature sensors that use RTDs as the sensing element.

RTDs are based on the principal that the electrical resistance of the wire is a function of the temperature, with the resistance increasing as temperature increases. The resistance varies nearly linearly with temperature per the Callendar Van-Dusen equation. The wire used in RTDs as the sensing element is usually constructed of platinum, copper, or nickel.  Platinum is the best material for this element, as it has the widest useful temperature range of these materials. It also has a very repeatable and linear temperature to resistance correlation. Continue reading “RTD Temperature Sensors”

Understanding Sensor Output Signals

Have you ever wondered why there are a multitude of sensor output signals that can be configured on pressure, temperature, humidity, or gas sensing instrumentation used in process or HVAC applications? Most of these offerings were originally setup to allow sensor manufacturers to better align with the inputs offered by manufacturers of programmable logic controllers (PLCs) and direct digital controllers (DDCs), which are used for controlling processes for both automation and HVAC control.

I’d like to focus on two of the most commonly used output signals and zero in on the advantages and/ or disadvantages these output signals offer. Two of the most commonly used output signals include analog current, typically 4 to 20mA, and analog voltage, typically 0-10V. Continue reading “Understanding Sensor Output Signals”

How the Sensor Market is Championing the Internet of Things (IoT)

The Internet of Things (IoT) is the concept of creating a large network of devices that all interact with each other to ultimately change the way we live and work. By connecting our phones, cars, and other devices to this network and linking them together with shared data/services, we have the potential to revolutionize the way we do everyday tasks. This innovation is at the root of ideas like autonomous vehicles and smart cities that improve efficiency and simplify complicated systems. From an industrial standpoint, the IoT can be applied anywhere from the factory to agricultural fields and offers the opportunity to place all the steps in a process onto an automated course held together by the overarching Internet. Continue reading “How the Sensor Market is Championing the Internet of Things (IoT)”