SPECIFICATION GUIDE

1.1DUCT MOUNTED AIRFLOW MEASURING SYSTEMS

  1. Provide where indicated, Duct Mounted Airflow Measuring Systems capable of continuously monitoring the duct air volumes they serve. Each system shall consist of a Pitot-type airflow sensing element arraysuitable for duct mounting and a [digital airflow signal processor][analog airflow transducer]. System components shall be by the same manufacturer to guarantee the overall accuracy and performance.
  2. Duct Mounted Airflow Sensing Element Arrays:
  3. Basis-of-Design Product: Subject to compliance with requirements, provide Paragon Controls Inc.; FE Seriesor equal as approved by the Engineer.
  4. Material: [Alloy6063-T5 anodized aluminum] [Type 316-L stainless steel] [Type 1 PVC].

Retain one of two first subparagraphs below when elements are required to be factory pre-mounted in a duct spool piece.

  1. Manifold sensing elements together in a [16 gage(1.5 mm) galvanized steel] duct section with 90 degree undrilled flanges, fabricated to duct size.
  2. Manifold Type 316L stainless steel duct mounted airflow sensing elements together in a [Type 304L][Type 316L] stainless steel duct section with 90 degree undrilled flanges, fabricated to duct size.

Retain subparagraph below when airflow-straightening sections are required

  1. Airflow Straightening: [Alloy3003 aluminum honeycomb with opening 0.5 inch (13 mm) high by 3 inches (76 mm) deep], [Type 304L] [Type 316L] stainless-steel-bonded honeycomb airflow straightening section.
  2. Designed and built to comply with and provide results according to accepted practice for duct system traversing defined in ASHRAE Handbook of Fundamentals, AMCA publication No. 203, and the Industrial Ventilation Handbook. Number of sensing ports on each element, and quantity of elements utilized at each installation, shall comply with ASHRAE111 for equal area duct traversing.
  3. Dual integral chambered design containing multiple total and static pressure sensing ports along leading edge of cylinder. Static pressure chamber shall incorporate dual offset static taps on opposing sides of averaging chamber to permit flow angle variations up to plus or minus 20 degrees in approaching airstream without affecting output value.
  4. Capable of producing steady, non-pulsating signals of true total and static pressure, with accuracy of plus or minus 2 percent of actual flow for operating velocities as low as 100 fpm (0.5 m per second). Signal amplifying sensors requiring flow correction (K factors) for field calibration are prohibited.
  5. Designed not to induce pressure drop greater than 0.18 inch at 4,000 fpm (5 mm at 20 m per second).
  6. Self-generated sound rating of less than NC40. Sound level within duct shall not be amplified, nor shall additional sound be generated.
  7. Approved by manufacturer for special configurations located outside of manufacturer's published installation guidelines, including requirements such as air equalizers and additional strategically placed measuring points.

Retain paragraph below to require microprocessor based digital airflow signal processors.

  1. Digital Airflow Signal Processors:
  2. Basis-of-Design Product: Subject to compliance with requirements, provide Paragon Controls Inc.; MicroTransEQor equal as approved by the Engineer.
  3. Span: Factory calibrated to match the application.
  4. Accuracy: Plus or minus [0.25] [0.1] percent of full scale including non-linearity, hysteresis, deadband and non-repeatability.
  5. Signal Conversion Resolution: 24-bit A/D and 12 bit D/A.
  6. Temperature Effects: Less than 0.025 percent full scale per degF (Less than 0.045 percent full scale per degC).
  7. Over-pressure: 5 psig proof, 10 psig burst (35 kPa proof, 69 kPa burst).
  8. Response: Less than 0.25 seconds for full scale input.
  9. Noise Filtration: Response time to reach 98 percent of a step change adjustable from 0 to 200 seconds in 1 second increments.
  10. Output: [4-20 mA] [0-5 Vdc] [0-10 Vdc].
  11. Enclosure: [NEMA 1 rated flame retardant ABS plastic] [NEMA 4X rated impact and corrosive resistant]
  12. Capable of twelve-point linearization and four-point flow correction.
  13. Large backlit LCD for configuration and local indication of measured process.
  14. Six button touch pad and password protected menus for field configuration of engineering units, process noise filtering, operating range, and alarm set points.

Retain optional features in first three subparagraphs below if required.

  1. Automatic Zeroing Circuit: For operating velocities below 1,266 fpm include an automatic zeroing circuit that is field configurable for frequency of activation between one and twenty four hours on 1-hour intervals. Signal processor output shall be locked and maintained at last given output value during automatic zeroing period so as not to interrupt automatic control process. Meter shall be auto calibrated to accuracy of plus or minus 1 count.
  2. Temperature Compensation: Capable of accepting temperature input signal for air temperature indication, temperature signal transmission for remote readout, and air density compensation for standard or actual airflow calculations.
  3. High/Lo Alarm: Contacts indicating low and/or high airflow conditions. Dry contacts shall be rated for 5 amps at 30VAC/VDC and 10 amps at 120VAC resistive load.
  4. Monitoring and configuration shall be performed through [LonWorks®][BACnet®-MS/TP] or [Modbus] communication network.

Retain paragraph below to require analog type airflow transducers.

  1. Analog Airflow Transducers:
  2. Basis-of-Design Product: Subject to compliance with requirements, provide Paragon Controls Inc.; FT/FIT Seriesor equal as approved by the Engineer.
  3. Span: Factory calibrated to match the application.
  4. Accuracy: Plus or minus [1] [0.5] percent of full-scale reading.
  5. Hysteresis: Plus or minus [0.05] [0.02] percent.
  6. Linearity: Plus or minus [0.8] [0.40] percent.
  7. Repeatability: Plus or minus [0.10] [0.05] percent.
  8. Temperature Effects: Less than 0.03 percent of full-scale reading per degF (less than 0.05 percent of full-scale reading per degC).
  9. Over-pressure: 5 psig proof and 25 psig burst (35 kPa proof and 172 kPa burst).
  10. Response: Less than 0.25 seconds for full span input.
  11. Noise Filtration: Low pass filter, factory set at 3.2 Hz.
  12. Output: [4-20 mA] [0-5 Vdc] [0-10 Vdc].

Retain optional features in first three subparagraphs below if required.

  1. Zeroing Valve: Integral manual zeroing valve to allow for field calibration of zero reference value without need for shutting operating system down.
  2. Digital Indication: Integral digital meter to indicate measured air volume.
  3. Magnehelic Pressure Gauge: Integral dual scale indicating meter operating independent of all other control devices. Top scale shall indicate measured air volume and bottom scale shall indicate air velocity.