User's Manual

ADCP-75-158 • Issue 1 • July 2003 • Section 5: Maintenance

Page 5-15

Figure 5-1. Cabinet Filter Removal and Replacement

5.3 Host Unit Fan Replacement Procedure

The HU is equipped with two cooling fans which are located on the right side of the HU

enclosure. The cooling fans blow cool air into the enclosure. Heated air is exhausted through the

vent openings on the left side of the enclosure. Replacement of the fans requires that the HU be

turned off for a short period of time. Use the following procedure to remove and replace the HU

cooling fans:

1. Before working on the HU or handling a fan, slip on an Electro-Static Discharge (ESD)

wrist strap and connect the ground wire to an earth ground source. Wear the ESD wrist

strap while completing each section of the fan installation procedure.

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

3. Place the HU On/Off switch in the OFF position (press O).

4. Remove the six flat-head screws (requires TORX screwdriver with T10 bit) that secure the

fan/grill assembly to the right side of the HU enclosure as shown in Figure 5-2. Save

screws for reuse.

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

exposed and the connectors are accessible.

6. Lift the small latch on each wiring harness connector and carefully unplug each connector

from the circuit board connector.

Warning: Electronic components can be damaged by static electrical discharge. To prevent

ESD damage, always wear an ESD wrist strap when working on the HU, STM, or LPA and

when handling electronic components.

18614-B

FILTER - PLACE FOAM

STRIP SIDE DOWN

SET SCREWS