User's Manual

ADCP-75-130 • Issue 3C • August 2006

Page 58

3. Notify the NOC or alarm monitoring system operator that the system is going offline.

4. Place the DHU or DEU AC power On/Off switch (see Figure 3 or Figure 7) in the OFF

position (press O).

5. Remove the six flat-head screws (requires TORX screwdriver with T15 bit) that secure the

fan/grill assembly to the side of the enclosure as shown in Figure 30 and save for reuse.

16172-B

Figure 30. Fan/Grill Assembly Removal

6. Carefully withdraw the fan/grill assembly from the enclosure until the wiring harness is

exposed and the connectors are accessible.

7. Lift the small latch on each wiring harness connector (see Figure 30) and carefully

unplug each connector from the circuit board connector.

8. Remove the four plastic rivets that secure the faulty fan to the grill by pushing outward

on rivet center post until the rivet can be withdrawn from the grill as shown in Figure 31.

9. Remove the faulty fan(s) from the grill and then locate the replacement fan(s).

10. Use the rivets removed in step 8 to secure the replacement fan to the grill. Orient the fan so

the wiring harness is on the top and the arrow on the fan housing faces into the enclosure.

11. Connect the two wiring harness connectors to the circuit board connectors.

12. Secure the fan/grill assembly to the side of the enclosure (see Figure 30) using the six

flat-head screws removed in step 5.