User's Manual

ADCP-75-158 • Issue 1 • July 2003 • Section 5: Maintenance
Page 5-17
© 2003, ADC Telecommunications, Inc.
5.4 Spectrum Transport Module Fan Replacement Procedure
The STM is equipped with a rear-mounted cooling fan. The rear fan exhausts heated air from
the STM housing. Replacement of the fan requires that the STM be turned off for a short period
of time and that the STM be removed from the outdoor cabinet or indoor mounting shelf. Use
the following procedure to remove and replace the STM cooling fan.
1. Before working on the STM 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 STM On/Off switch in the OFF position (press O).
4. Disconnect the various power, fiber optic, service, alarm wiring, and coaxial cable
connectors from the STM front panel as specified in Figure 5-4.
Figure 5-4. Spectrum Transport Module Cable Connections
5. Loosen the captive screws that secure the STM to the RU outdoor cabinet or indoor
mounting shelf and carefully withdraw the STM from its mounting slot.
6. Remove the four pan-head screws (requires TORX screwdriver with T10 bit) that secure
the fan/grill assembly to rear side of the STM housing as shown in Figure 5-5. Save screws
for reuse.
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.
18661-A
Disconnect AC
power connector
Disconnect alarm
connector
Disconnect antenna
connector
1
2
3
4
5
Disconnect optical fiber
connectors. Place a dust
cap over each cable
connector and port adapter.
Disconnect service
connector (if present)
18661-A
Disconnect AC
power connector
Disconnect alarm
connector
Disconnect antenna
connector
1
2
3
4
5
Disconnect optical fiber
connectors. Place a dust
cap over each cable
connector and port adapter.
Disconnect service
connector (if present)