Belfort AWOS, Maintenance Manual

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BELFORT
INSTRUMENT
Proprietary Information
TOOLS & PARTS REQUIRED
Slotted screw driver
Removal Procedur
es: Refer to figure 13.
1. At the DATU display terminal, issue a NOTAM advisory to alert users that the Belfort
AWOS system is being serviced prior to beginning investigation of this fault. The NOTAM
to be issued is "
Belfort AWOS system being serviced, do not use current weather data
outputs ." Verify that this NOTAM advisory is displayed on the operator screen prior to
beginning this maintenance tasks. Refer to the "Belfort AWOS Operator Manual" for
instructions on how to enter and delete NOTAMs.
2. Open the power enclosure. Examine the Surge Suppressors for either of the following
conditions:
a. Either of the two neon indicators is out;
b. The neon indicator is a color other than neon orange.
3. If either of the failure indicators above has occurred, perform the following instructions.
4. Power down the power enclosure by opening the AC and DC circuit breakers.
5. Use a DMM set to AC volts, and measure the voltage on the AC input terminals of the
power supply. The voltage read should be <1.0 vac. This confirms that the AC voltage is
turned off.
6. Cut the ty-wrap off of the wiring harness from the circuit breaker to the surge suppressor.
7. Examine the wiring harness and locate the wires that go to the suppressor. One black wire
goes to the circuit breaker. One black wire go to the Black wire terminal on TB2. The
white wire goes to the White wire terminal on TB2. The green wire goes to the green wire
terminal on TB2.
8. Disconnect the suppressor wires from the terminal blocks by loosening the terminal block
screws, while documenting what wire comes out of which screw terminal.
9. Unscrew the suppressor mounting bracket from the mounting plate.
10. Mount the new suppressor to the mounting plate using existing screws and mounting holes.
11. Add the suppressor wires to the harness and route them to the terminal block terminals as
documented in step 8.
12. Connect the new suppressor wires to the same terminals as indicated in step 7. Either black
wire can be connected to either black wire termination location.
13. Use ty-wraps to secure the wire harness.
14. Turn the AC circuit breaker on.
15. If the new suppressor is good, both neon orange indicators will be illuminated.
16. If both indicators are not on, then open the AC circuit breaker and examine the wiring using
the wiring diagram provided in the Installation and Checkout manual.
17. If the wiring is correct turn the AC circuit breaker on and measure the voltage at the two
black wires coming from the suppressor.
18. If both voltages are 110 to 120vAC, then contact the Belfort support for further instructions.