Bimetal Thermometers

Dwyer Instruments, Inc. offers many temperature measuring products that use bimetal sensors as the sensing element.

Bimetal Thermometers measure temperature based on the differences in thermal expansion properties of metals. Pieces of metals with different thermal expansion coefficients are attached to each other in an assembly.

As the temperature applied to the metal sensor assembly increases, the metal strip with the larger temperature coefficient of expansion expands more.  Continue reading “Bimetal Thermometers”

Weatherproof Enclosure Ratings: Speaking the Secret Language of NEMA and IP

Understanding the necessary requirements for your product’s enclosure ratings is important, particularly when looking to gain the optimum life from your product while avoiding any safety concerns. Included below is a straight forward easy to understand overview of enclosure ratings, including NEMA types, IP ratings, and the difference between the two. We will be looking at these two common standards for industrial enclosures, what they equate to, some alternatives, and how to best choose the right one for your application. Continue reading “Weatherproof Enclosure Ratings: Speaking the Secret Language of NEMA and IP”

Control Valve Actuator Sizing and Valve Action Selection

Control valves are used to change process conditions such as flow, temperature, level, and pH. A complete control system would include: a sensor, controller, positioner or current to pressure transducer, and control valve.  Globe valves, such as the Dwyer Series 2000VA/ 3000WA Hi-Flow™ Control Valve, are a very common type of control valve.

Hi-Flow™ Valve

The Dwyer Hi-Flow™ Series control valves have pneumatic actuators that modulate the valve for flow control. The opening, closing and throttling of the valve plug is accomplished by varying the air pressure to the diaphragm in the actuator. Typically the control pressure signal is 3 to 15 psig. There are two types of actuators: Air-To-Lower and Air-To- Raise. Continue reading “Control Valve Actuator Sizing and Valve Action Selection”