Thermal Flow Meters with Superior Technology

PowerPro™ Sensor

Used in Fox Thermal Models FT2A and FT3, the Fox Thermal PowerPro™ Sensor operates at a higher power level than other competitive thermal technologies, providing better response time and wider turndown. Compared to a typical Differential Pressure(DP) type flowmeter (see inset), thePowerPro™ sensor offers better low flow or low-end sensitivity. The PowerPro™ sensor also provides exceptional accuracy at high velocities - up to 60,000 SFPM air.

DDC-Sensor™ Technology

The Fox Thermal DDC-Sensor™ is a new state-of-the-art sensor technology used in the FT1, FT4A, and FT4X flow meters. The DDC-Sensor™ is a Direct Digitally Controlled sensor that is interfaced directly with the microprocessor for more accuracy, speed, and programmability. Like thePowerPro™ Sensor, the DDC-Sensor™accurately responds to changes in process variables (gas flow rate, pressure, and temperature), which are used by the microprocessor to determine mass flow rate, totalized flow, and temperature.

Constant Temperature Differential 

Fox Thermal flow meters use a constant temperature differential (ΔT) technology to measure air and gases' mass flow rate. The thermal mass flow sensor consists of two Resistance Temperature Detectors (RTDs). The sensor elements are constructed of a reference-grade platinum wire around ceramic mandrels inserted into a stainless steel or Hastelloy tubes.

The reference RTD measures the gas temperature. The heated element is kept at a constant temperature, and the instrument electronics measure the gas flow's cooling effect. The electrical power required to maintain a constant temperature differential is directly proportional to the process gas's mass flow rate. The microprocessor then linearizes this data to deliver a 4-20mA output signal.

For more information in Nebraska, Iowa, Missouri, and Kansas contact Power Specialties, Inc. Call them at (816) 353-6550 or visit their website at https://powerspecialties.com.

Benefits of Thermal Mass Flow for the Measurement of Gases

There are quite a few technologies available to measure flowing gases. When the comparisons are complete, most outcomes point out that thermal mass flow technology is superior to others. This short video explores those benefits and demonstrates why thermal mass flow measurement technology is the right choice for your gas flow measurement application.

Benefits of Thermal Mass Flow Technology:

• Direct mass flow measurement of air and gases in standard volumetric units (e.g., SCFM or NM3/H) or mass units (e.g., LBS/M or KG/H)
• No additional pressure or temperature compensation required
• Repeatability and exceptionally broad measurement range: up to 1000:1 (100:1 typical)
• Standard linear 4-20mA output proportional to mass flow rate
• Low pressure drop
• No moving parts
• Cost-effective
• Insertion, Inline & remote* styles
• Measures flow rate and temperature

Along with these benefits, Fox Thermal improved thermal mass flow with their DDC-Sensor (Digital Sensor Technology). Because of this unique development, Fox Thermal leads the industry for accuracy, quality, and innovative design.

For more information, contact Power Specialties. Call them at (816) 353-6550 or visit their website at https://powerspecialties.com.

Top Five Tips for Choosing a Flow Meter

The wide range of flow technology alternatives on hand can make it a confusing task to select the right flowmeter. A wide range of factors can influence the selection of flowmeter, of which only one is the cost. Including the fluid type, application environment, working parameters such as temperature, pressure and flow rate, flow meter technology, requirements for precision and repeatability, reliability, installation limitations, maintenance requirements, and instrument life cycle are many considerations to consider. Below are our top five criteria when selecting a flow meter.

1. Regulations, compliance
   1. What local, state, regional or national regulations impact the measurement location?
   2. Are there additional recording, data logging or calibration verification requirements to comply with regulations?
   3. What agency approvals must the flow meter have?
2. Fluid type at the measurement point
   1. Dry or wet gas conditions may affect sensors
   2. Corrosive components in oil may affect sensor material selections
   3. Flow back contains mixtures of oil, gas, solids, chemicals, and water that must be separated
3. Fluid conditions
   1. Does the accuracy spec of the flow meter change based on the composition of the fluid type?
   2. Does the fluid composition change over time?
   3. What is the pressure and velocity in the pipe? Is it constant?
   4. Are there installation limitations (straight pipe runs, limited access to the pipe, tight spaces)?
4. Additional equipment
   1. Does the flow meter require additional equipment or instrumentation to operate successfully at the point of measurement?
5. Additional calculations
1. Will you need to do additional calculations to determine an accurate flow rate? 

List is courtesy of Fox Thermal.

For more information about flow meter selection, contact:

Power Specialties, Inc.
9118 E. 72nd Terrace
Raytown, MO 64133
Toll Free: (800) 432-6550
Phone: (816) 353-6550
Fax: (816) 353-1740
www.powerspecialties.com