We met with an original equipment manufacturer (OEM) last year, who was working on a new design for rooftop air handling equipment. Part of the their design utilized water flow for cooling in a loop.
Low or no-flow conditions can cause major damage to expensive pumps, motors, and other equipment, which could result in extensive downtime and repair costs. In order to prevent this, the customer needed an inexpensive, but reliable and robust method for proving water flow. Continue reading “Proving Water Flow in Rooftop Air Handlers”
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”
Air flow pressure switches and differential pressure switches work just like the light switches we have in our living rooms at home: when they are switched on, the switch makes contact, closes the circuit, and turns on. When they are switched off, the circuit is broken and power turns off. With air flow switches, instead of being manually switched, the air flow switch closes or opens the contact by reacting to changes in the air pressure at a pre-set actuation point, and turns on and off accordingly. These air pressure switches may be used to start/stop motors or fans, open/close dampers or louvers, sound alarms, and more. Continue reading “Let’s Chat About Air Pressure Switches!”
In the past few years, oil production in the United States has skyrocketed. In fact, the U.S. is out-producing many OPEC countries and is currently on track to become one of the largest oil-producing countries in the world, alongside Russia and Saudi Arabia. The top oil producing region in the U.S. is known as the Permian Basin, which includes parts of Texas and New Mexico. Other major oil-producing states include Colorado, Oklahoma, North Dakota, Alaska, and California.Continue reading “Hydraulic Fracturing for Oil Extraction”
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.