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For high line pressure, high differential pressure applications

The pressure difference across an orifice plate, filter, pump, valve, etc. can be sensed with two pressure transducers such as the Model 206. One transducer measures the high side pressure (P₁) while the other measure the low side pressure (P₂). Pressure media can be any liquid or gas compatible with 17-4 pH stainless steel.

Why are industry leaders using remote sensors?

Wet-to-wet differential pressure transducers have undergone several significant design and technological improvements recently. The most dramatic of which is the ability to install these units with remote sensors, rather than with traditional embedded sensing elements. A contractor can now easily install remote sensors directly into the pipes while an electrician makes electrical connections between the remote sensors and the transducer via cables or conduit. For industrial applications, contractors can order plumbing-ready cable versions with up to 30 feet of cable. When the local electrical code requires conduit, typically for projects like schools or municipal buildings, contractors can order units in the conduit version.

Traditional vs. Remote Sensor Installation

To better understand the labor and material savings made possible by remote sensors, it is important to compare the traditional method of installing differential pressure transmitters with the new method of installing remote sensors. On a typical job using the conventional method, the mechanical contractor first installs taps with shutoff valves—usually a ball or petcock valve—in the desired locations in the mechanical piping.

After reviewing the top 5 product considerations (pressure, media, temperature, and environment) in which the pressure transducer will be installed, it’s time to look at transducer construction, circuit design and the pressure transducer manufacturer's supply chain.

When selecting multi-range pressure sensors, there are certain things to be cautious of. Often a "one size fits all" pressure transducer is chosen for expected cost savings and inventory control; however this decision turns out to be a bad idea. Issues arise with inaccuracy and poor stability on low range applications where the range output adjustment is simply pushed too far.

Liquid Level

The pressure measured at the bottom of a liquid filled tank is proportional to both the height (head) and density of the liquid. For best results the pressure should be sensed by a pressure transmitter mounted at the lowest point possible on the tank, as shown in Figure 1.

On the heels of an economic crisis, the President of the United States signed the American Recovery & Reinvestment Act (ARRA) in 2009 with the goal of:

Capacitive pressure transducers have earned a reputation for consistently high accuracy and unmatched long-term stability. These sensors find broad application in areas where characteristics rate from important to vital. A few of these include:

Low Pressure Measurement
Low pressure measurements are required in various applications such as air flow, static duct and clean room pressures in heating, ventilating and air conditioning (HVAC) and energy management systems. Other applications include use in medical instrumentation, environmental pollution control, boiler combustion efficiency and a wide variety of research and development requirements. While this discussion will center mainly on air flows and pressures, the same principles also apply to liquids. As there are both pressure transducers (voltage output proportional to applied pressure) and pressure transmitters (current output proportional to applied pressure,) we will refer to each as pressure sensors in this application note.