Flow configuration - Johnson Controls - LIT-12014081 - RA-1270 - Airflow Measuring Station - AFMS

RA-1270 Advanced Thermal Dispersion Fan Inlet Airflow and Temperature Measuring System Technical Bulletin

Johnson Controls
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Use the Operator Menu selection to enter application-specific data to configure the RA-1270 host monitor for a unique application. Data includes: units of measure, fan diameters, flow units, site elevation, system ranges, and zero cutoff. See the following table for configuration options.

Table 1. Flow configuration selections
Configuration selections Configuration options
Fan Diameter Select the fan or fan array and enter the fan diameter: 10 in. to 48 in (25.4 cm to 60.96 cm).

Select Fan Array to configure the same diameter for all fans. If you require a specific area, use UP or DOWN on the area display screen to change from Confirm to Edit to enable a manual area value entry.

Site Elevation Enter the site elevation from 0 ft to 15,000 ft (0 m to 4572 m).
Relative Humidity Enter the relative humidity from 0% RH to 100% RH, 1% at a time.
Flow Units Enter the flow units. See Table 2 for available units.
Output Lockout Enter the output lockout from 0 fpm to 750 fpm (0 mps to 3.81 mps). When the measured velocity of a fan is less than this amount, the output remains zero.
Note: Press ESC at any time to return to the previous menu and exit without changing any settings.

To configure flow selections, complete the following steps:

  1. While in the Operator Menu, use UP or DOWN to scroll to Flow Config.
  2. Press ENTER to enter the Flow Configuration Menu. The display shows Fan Diameter > Site Elevation.
  3. Select Fan Diameter and press ENTER to prompt the user to confirm the requirement for a new calibration if the diameter is modified.
  4. Press ENTER to select the fan or fan array to view and edit its diameter. Select Fan Array to set the same diameter for all fans.
  5. When you view the calculated area, use UP or DOWN to select between Confirm and Edit and press ENTER to select.
  6. Select Confirm to accept the entered diameter and calculated area. Select Edit to enable manual entry for the area and to change the diameter to match the entered area.
  7. Use UP or DOWN to change the setting. When the required setting displays, press ENTER. The new setting stores in memory and the display progresses through the required values for the selected shape and saves each value as they are confirmed. With all required values entered, the display returns to the Flow Configuration Menu.
  8. Use UP or DOWN to select and change the remaining parameters within the Flow Configuration Menu. Press ENTER to change the selected setting.
    Note: See the following tables for the list of available selections for the appropriate Flow Type.
    Table 2. Volumetric units of measurement from flow unit selection and display units
    Flow units Metric units Imperial units
    Actual per sec ALPS ACFS
    Actual per min ALPM ACFM
    Actual per hour ACMH ACFH
    Standard per sec SLPS SCFS
    Standard per min SLPM SCFM
    Standard per hour SCMH SCFH
    Table 3. Volumetric units of measurement
    Volumetric units of measurement Display
    Actual cubic feet per second ACFS
    Actual cubic feet per minute ACFM
    Actual cubic feet per hour ACFH
    Actual liters per second ALPS
    Actual liters per minute ALPM
    Actual cubic meters per hour ACMH
    Standard cubic feet per second ACFS
    Standard cubic feet per minute SCFM
    Standard cubic feet per hour SCFH
    Standard liters per second SLPS
    Standard liters per minute SLPM
    Standard cubic meters per hour SCMH
  9. To return to the Operator Menu, scroll to Exit this Menu in the Flow Configuration Menu and press ENTER.
  10. Alternatively, press ESC to return to the Operator Menu. Press MENU to return to the normal display mode.