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Velocity Flow Switches Specifications

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Pipe Size and Style




   Pipe Diameter
 
     The diameter of the process pipe to be monitored.
 
   Search Logic:      User may specify either, both, or neither of the "At Least" and "No More Than" values. Products returned as matches will meet all specified criteria.
   Mounting Type       
   Your choices are...
 
      
 
   In-line
 
     In-line flow meters are installed directly in the process line.  They have a variety of end-fittings, including flanges, threads, and compression fittings. Typically, in-line flow meters require a straight run of pipe for installation.
 
   Insertion Type
 
     Devices are inserted perpendicular to flow path. They usually require a threaded hole in the process pipe or another means of access.
 
   Non-Invasive
 
     Non-invasive flow meters do not require mounting directly in the process flow and can be used in closed piping systems. Ultrasonic flow meters such as Doppler devices may use this type of mounting to read the flow through the pipe.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   End Fittings       
   Your choices are...
 
      
 
   Clamp
 
     Devices are inserted parallel to the flow path and clamped between two existing process pipes. External clamp-on flow meters are non-invasive. They do not require mounting directly in the process flow and can be used in closed piping systems.  Ultrasonic, or Doppler, flow meters may use this type of mounting to read the flow through the pipe.
 
   Compression
 
     Compression fittings tighten down a sleeve or ferrule over a joint to prevent leakage.
 
   Flanged
 
     Devices are inserted parallel to the flow path, usually between two pieces of existing, flanged process pipes. Circular or square flanges are used to connect the fitting, typically via bolting or welding.
 
   Plain End
 
     Devices have a plain, straight-pipe end that can be inserted into the bell end of the connecting pipe.
 
   Socket Weld / Union
 
     The end fitting is designed for welding or soldering and can be a weld neck.
 
   Threaded
 
     Devices are inserted parallel to the flow path and threaded into two existing process pipes. National pipe thread (NPT) is the most common thread type. 
 
   Tube End / Hose Nipple
 
     Tube-end or hose-nipple is a common description for a short piece of pipe, usually with male threaded ends.
 
   VCO® / VCR®
 
     VCO® and VCR® connections are proprietary, threaded fittings for vacuum applications that use the Swagelok design. VCO® fittings have an O-ring face seal.  VCR® fittings have a metal gasket face seal. VCO and VCR are registered trademarks of Cajon Company. Swagelok is a registered trademark of Swagelok Co.
 
   Other
 
     Other unlisted, specialized, or proprietary configurations.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
Media Specifications
Typically, the process media type is determined by the meter technology. For additional guidance, refer to information about meter technologies, or consult the manufacturer.



           
   Your choices are...
 
      
 
   Gas
 
     Devices measure the flow of gases.
 
   Liquid
 
     Devices measure the flow of liquids.
 
   Steam
 
     Devices can accommodate mixed-phase materials such as steam.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   Suspended Solids / Slurries
 
     Devices can accommodate liquids with suspended solids (slurries). Typically, the material types are determined by the meter technology chosen. For additional guidance, refer to information about meter technologies or consult the manufacturer.
 
   Search Logic:      "Required" and "Must Not Have" criteria limit returned matches as specified. Products with optional attributes will be returned for either choice.
   Media Temperature
 
     Media temperature range is the maximum media temperature that can be monitored. It is usually dependent on construction and liner materials.
 
   Search Logic:      User may specify either, both, or neither of the "At Least" and "No More Than" values. Products returned as matches will meet all specified criteria.
Operating Performance
A meter's performance can be determined by its turndown ratio. Turndown ratio is the effective dynamic or operating range of the flow meter. For example, if a 500 SCCM flow rate device has a turndown ratio of 50:1; it will operate effectively and resolve flow down to 10 SCCM. If the same device has a turndown of 100:1, then it will resolve effectively to 5 SCCM.



   Velocity Flow Rate Range
 
     Velocity flow range is range of flow in distance/time. This specification applies to velocity flow sensors and meters.
 
   Search Logic:      User may specify either, both, or neither of the limits in a "From - To" range; when both are specified, matching products will cover entire range. Products returned as matches will meet all specified criteria.
   Operating Temperature
 
     The temperature range over which the device must operate.
 
   Search Logic:      User may specify either, both, or neither of the limits in a "From - To" range; when both are specified, matching products will cover entire range. Products returned as matches will meet all specified criteria.
   Operating Pressure
 
     Operating pressure is the maximum head pressure of the process media that devices can withstand.
 
   Search Logic:      User may specify either, both, or neither of the "At Least" and "No More Than" values. Products returned as matches will meet all specified criteria.
Switch Specifications




   Switch Type       
   Your choices are...
 
      
 
   Electro-Mechanical Switch
 
     Devices use mechanical contacts, relays, reed switches, etc.
 
   Solid-State Switch
 
     Devices use electronic switches with no moving parts.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   Normal State       
   Your choices are...
 
      
 
   Normally Open (NO)
 
     The switch is normally open (NO).
 
   Normally Closed (NC)
 
     The switch is normally closed (NC).
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   Poles       
   Your choices are...
 
      
 
   Single Pole (SP)
 
     A single pole (SP) switch has a single set of contacts for switching just one electrical line.
 
   Double Pole (DP)
 
     A double pole (DP) switch has a double set of contacts for switching two electrical lines simultaneously.
 
   More Than 2 Poles
 
     Switches have more than two sets of contacts.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   Throws       
   Your choices are...
 
      
 
   Single Throw (ST)
 
     Single throw (ST) switches are simple, on/off devices.
 
   Double Throw (DT)
 
     With double throw (DT) switches, a common contact is switched between two contacts.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
Additional Output Options




   Electrical Output       
   Your choices are...
 
      
 
   Analog Current
 
     Analog current levels (transmitters) such as 4 – 20 mA are suitable for sending signals over long distances. A current is imposed on the output circuit proportional to the measurement. Feedback is used to provide the appropriate current regardless of line noise and impedance.
 
   Analog Voltage
 
     Analog voltage outputs are simple, usually linear functions of the measurement.
 
   Frequency
 
     Frequency or modulated frequency outputs include amplitude modulation (AM), frequency modulation (FM), sine waves, and pulse trains.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
   Interface Options       
   Your choices are...
 
      
 
   Serial / Digital
 
     Flow meters can provide signal outputs in serial, parallel, Ethernet or other digital formats. Devices with a serial/digital interface can provide a process variable for measurement, but do not include communication lines.
 
   Network / Fieldbus
 
     Devices output signals that are formatted according to an industrial fieldbus protocol such as CANbus, PROFIBUS®, or SERCOS; a networking protocol such as Ethernet; or another industrial automation protocol. PROFIBUS is a registered trademark of PROFIBUS International.
 
   Other
 
     Other unlisted, specialized, or proprietary interface options.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
Features




   Measures Density
 
     The sensor or meter also measures density.
 
   Search Logic:      "Required" and "Must Not Have" criteria limit returned matches as specified. Products with optional attributes will be returned for either choice.
   Measures Level
 
     The sensor or meter also measures level.
 
   Search Logic:      "Required" and "Must Not Have" criteria limit returned matches as specified. Products with optional attributes will be returned for either choice.
   Measures Temperature
 
     The sensor or meter also measures temperature.
 
   Search Logic:      "Required" and "Must Not Have" criteria limit returned matches as specified. Products with optional attributes will be returned for either choice.
   Features       
   Your choices are...
 
      
 
   Audible or Visual Alarms
 
     Instruments have audible or visual alarms to alert users to dangerous conditions.
 
   Averaging / Multi-Insertion
 
     Multi-insertion flow meters determine the flow rate by taking flow rate measurements across several points in the flow path.
 
   Controller Functions
 
     Devices have or receive sensor input, provide control, (limits, PID, logic, etc.) and output a control signal.
 
   Programmable
 
     Typically, programmable meters include a built-in microprocessor. They can be adjusted electronically for different materials, ranges, outputs, etc.
 
   Recorder / Totalizer Functions
 
     Totalizer functions totalize the amount of material, media, or process variable controlled. A recorder function may be a datalogger that logs system or process variables and/or control commands for later viewing or analysis.  A chart recorder that can plot (chart) flow history or give total flow for a given unit of time may also be available.
 
   Sanitary
 
     Devices are designed for use in sanitary environments, such as in medical or food processing applications.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
Meter Technology




           
   Your choices are...
 
      
 
   Differential Pressure Meter
 
     Differential pressure meters (DP) include orifice plates, venturi tubes, flow nozzles, cone types, Pitot tubes, target meters, elbow tap meters and rotameters. The basic operating principle of differential pressure flowmeters is that the pressure drop across the meter is proportional to the square of the flow rate. The flow rate is obtained by measuring the pressure differential and extracting the square root.

Differential pressure meters have a primary and secondary element. The primary element causes a change in kinetic energy, which creates the differential pressure in the pipe. The unit must be properly matched to the pipe size, flow conditions, and the liquid's properties. In addition, the measurement accuracy of the element must be accurate over a reasonable range. The secondary element measures the differential pressure and provides the signal or read-out that is converted to the actual flow value.
 
   Positive Displacement
 
     Positive displacement (PD) flow meters are used to take direct measurements of liquid flow. They divide the liquid into specific increments which are moved on. The total flow is an accumulation of the measured increments, which can be counted by mechanical or electronic techniques. Positive displacement flow meters are often used for high-viscosity fluids.
 
   Velocity Meter
 
     Velocity-type meters are devices that operate linearly with respect to the volume flow rate. Because there is no square-root relationship (as with differential pressure devices), their range ability is greater. Examples of velocity meters include turbine meters, electromagnetic meters, vortex meters, and ultrasonic meters.
 
   True Mass Flow Meter
 
     True mass flow meters directly measure the mass rate of flow. They include thermal meters and Coriolis meters. Thermal meters use a heated sensing element isolated from the medium flow path. The flow stream conducts heat from the sensing element. The conducted heat is directly proportional to the mass flow rate. Typically, thermal meters are used for gas flow rates. With Coriolis meters, fluid is passed through a small, vibrating flow tube. The resulting deflection of the flow tube is proportional to the mass flow rate of material.
 
   Search Logic:      All products with ANY of the selected attributes will be returned as matches. Leaving all boxes unchecked will not limit the search criteria for this question; products with all attribute options will be returned as matches.
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