Dwyer Instruments offers many electrical switch products that make or break a contact based on sensing a parameter such as pressure, temperature, level, and so on.
Most switches are single pole double throw, often referred to as SPDT. This type of switch has one normally open contact and one normally closed contact. Switches can also be double pole double throw, or DPDT, that have two normally open and two normally closed contacts. Single pole single throw switches with just one contact are also available and are specified to be either normally open or normally closed.
Dwyer Instruments, Inc. offers many flow measuring products including our very popular variable area flowmeters, often called rotameters. Dwyer manufactures variable area flowmeters in polycarbonate, poylsufone, fluoropolymer, acrylic, glass, and metal. Please see the Dwyer website for more details on these products.
Infrared Thermometers infer the temperature of an object by measuring the infrared thermal radiation emitted from the object. Objects at thermal equilibrium must balance the energy that is entering the object with the energy that is leaving the object. Often, the energy leaving the object is emitted as electromagnetic radiation. Continue reading “Infrared Thermometers”
Calibrating measurement instrumentation is something that should never go overlooked. To calibrate instrumentation means to determine, check, or rectify the graduation of any instrument giving quantitative measurement. Calibrating a device ensures that the instrument will properly measure within the desired range for your application. This is important because a properly calibrated measurement device will help the user to maintain his or her system. A device can be calibrated either at the factory where the device was manufactured or within the field. Calibration certificates may be obtained once a device has been calibrated. Continue reading “The Importance of Calibrating Measurement Instrumentation”
Dwyer Instruments, Inc. offers a multitude of sensors for monitoring air velocity in HVAC systems. Some of this instrumentation has a simple construction (Pitot tubes, for example) while others are more complex, such as hot-wire anemometers.
The initial term and first “hot-wire anemometer” was developed back in 1914 by Louie Vesso King. He is also accredited for King’s Law, which mathematically describes heat transfer in air flows using a heated wire. As the air moves over the wire, it causes a loss of temperature in the wire and removes some of the wire’s heat energy. Continue reading “Understanding Air Velocity Sensors”