Variable Area Flow Corrections

Variable Area Flowmeters

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, the Series RM and LFM; in acrylic, the Series VF; and in glass, the Series VA and DR.

Visi-Float® Flowmeter Series VFCII

Variable area flowmeters have scales calibrated for specific media at specific conditions. Most commonly, the flowmeters are calibrated for air for gas use, and water for liquid use, at standard atmospheric conditions of 70 degrees Fahrenheit and 14.7 PSIA, which is 0 PSIG.  When using the flowmeter in conditions other than these standards, the flow reading will not be accurate and corrections will need to be made. Continue reading “Variable Area Flow Corrections”

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”

Ask the Expert – Hazardous Area Humidity/Temperature Transmitter

Humidity/ Temperature Transmitter, Series RHP

Question: I have a new project coming up, and I am considering using the Series RHP Humidity/Temperature Transmitters. However, the instrumentation needs to be suitable for use in a hazardous area. Would the Series RHP work, or do you have a different instrument that you would recommend for this application? Continue reading “Ask the Expert – Hazardous Area Humidity/Temperature Transmitter”