Belfort AWOS, Maintenance Manual

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BELFORT
INSTRUMENT
Proprietary Information
9.
Hold down the “ctrl” key and type the letter “V” then type the word “foggy” in lower case
letters when prompted for the password.
10.
Type “FT” then press <enter> to run diagnostics, if the first 2 characters are FP, sensor is OK,
FF indicates a failure and further diagnostics are necessary (see troubleshooting section of this
manual). Type “FJ” to start streaming data.
11. Check the state of calibration first. Allow the measured visibility to settle for 5 minutes. If
the ExtCo (the number in the last numerical column on the right) is within 5% of the value
marked on the scatter plate, no recalibration is required. If recalibration is needed, proceed to
the next step.
12. The zero-state calibration must be done first. Place the opaque filters (the triangle shaped
pieces of rubber) on the receiver and transmitter hoods as close to the glass windows as
possible. The filters are 5/8 thick rubber, triangular in shape, with ears that hook over the
transmitter and receiver hoods to secure them in place. They may be attached easily near the
mid-point of the hood and slid back to the window as shown in Figure 3c.
Figure 3c
Installation of Opaque Filters on
Transmitter and Receiver Hoods
13.
Type “FZ” then press <enter> on the terminal. Answer “Y” when prompted “are you sure”
question and wait approximately five (5) minutes for the routine to finish and prompt for
acceptance. This acceptance prompt allows you to recover from an accidental invocation of
the routine. Acceptable values for the zero offset are between –0.01 and +0.01. If the zero
offset value displayed is acceptable, type “Y” and then press <enter>. The new value will be
written to EEPROM, it will be discarded if you answer “N”. Answer yes and press <enter>
when prompted with the “OK to save TxPwrCal?” Question. If the zero offset value displayed
is out of range, then confirm the proper installation of the opaque filters and rerun the “FZ”.
If the “FZ” is still out of range, then the instrument should be considered faulty and taken out
of service.
Follow the Belfort AWOS System Component Failure Instructions in Section
5.10.
14. Remove the opaque filters from the hoods.
15. The span-state calibration requires the use of the scatter plate installed as shown in figure 3.a
16. Install the scatter plate (See figure 3b) and record the Cal_ExtCo marked on the scatter plate.