MAINTENANCE
Fan Assembly Trouble
The fans should always be operating when the system is receiving ac power
and the cabinet switch is turned on. If the fans are not operating, be sure that
the system is receiving ac power.
if the system is receiving power and the fans are still not operating, the ac
power connection to the fan assembly is faulty or the fans themselves are
faulty (for example, burned out motors).
To check the ac power connection to the fan assembly, first unplug the
power cord, and then remove the four No. 6-32 screws at the corners of the
assembly. Carefully lift the fan assembly away from the cabinet. Check the
two modular plugs attached on the left side of the assembly. If the plugs are
securely attached, the fan assembly itself is faulty and must be replaced.
To replace the fan assembly, remove the modular plugs at the left side of the
assembly. Reconnect these plugs to a known good fan assembly, and
reinstall the new fan assembly by setting it in place in front of the power
supply and replacing the four No. 6-32 screws at the corners of the
assembly. (Without fans, the power supply will overheat and the system will
automatically shut down.)
Danger:
Whenever the power supply shuts itself down (due to
overheating, shorting, etc.), unplug the power cord and
wait at least 5 minutes before restoring power.
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Summary of Contents for Network Adapter 25
Page 1: ...AT T AT T System 25 Installation and Maintenance Manual 555 540 103 B November 1995 ...
Page 18: ...APPENDIX F Administration Error Messages GLOSSARY I N D E X F 1 G 1 I 1 viii ...
Page 31: ...INSTALLATION MOUNTING CENTERS WHEN FLANGES ARE OVERLAPPED Figure 2 2 617A Panel 2 7 ...
Page 33: ...INSTALLATION Z21OA1 ADAPTER Y ADAPTER WP90851 L1 858A ADAPTER Figure 2 3 SIP Adapters 2 9 ...
Page 50: ...INSTALLATION Figure 2 10 Three Cabinet System Front View With Covers Removed 2 26 ...
Page 51: ...INSTALLATION Figure 2 11 Position of Shorting Plugs on CPU Memory Circuit Pack 2 27 ...
Page 72: ...INSTALLATION UPPER ADAPTER MOUNTING CLIP Figure 2 18 Mounting Adapters ...
Page 85: ...INSTALLATION 2 61 ...
Page 92: ...INSTALLATION 2 68 ...
Page 103: ...INSTALLATION Figure 2 32 10B Emergency Transfer Unit 2 78 ...
Page 104: ...INSTALLATION Figure 2 33 Emergency Transfer Unit Connections 2 79 ...
Page 109: ...INSTALLATION Figure 2 35 Attendant Console With DXS Console 2 84 ...
Page 146: ...INSTALLATION 2 119b This page intentionally left blank November 1995 ...
Page 153: ...INSTALLATION This page intentionally left blank 2 124b November 1995 ...
Page 223: ...MAINTENANCE Figure 4 2 Clearing Supply Troubles Sheet 1 of 2 4 47 ...
Page 224: ...MAINTENANCE Figure 4 2 Clearing Power Supply Troubles Sheet 2 of 2 ...
Page 225: ...MAINTENANCE Figure 4 3 Clearing CO Trunk Troubles 4 49 ...
Page 226: ...MAINTENANCE Figure 4 4 Clearing 4 Wire Tie Trunk Troubles Sheet 1 of 4 4 50 ...
Page 227: ...MAINTENANCE Figure 4 4 Clearing 4 Wire Tie Trunk Troubles Sheet 2 of 4 4 51 ...
Page 228: ...MAINTENANCE Figure 4 4 Clearing 4 Wire Tie Trunk Troubles Sheet 3 of 4 4 52 ...
Page 229: ...MAINTENANCE Figure 4 4 Clearing 4 Wire Tie Trunk Troubles Sheet 4 of 4 4 53 ...
Page 231: ...Figure 4 6 Clearing Tie Trunk Troubles Sheet 1 of 5 4 55 ...
Page 232: ...MAINTENANCE 6 7 8 9 10 Figure 4 6 Clearing Tie Trunk Troubles Sheet 2 of 5 4 56 ...
Page 233: ...MAINTENANCE Figure 4 6 Clearing Tie Trunk Troubles Sheet 3 of 5 4 57 ...
Page 234: ...MAINTENANCE Figure 4 6 Clearing Tie Trunk Troubles Sheet 4 of 5 4 58 ...
Page 235: ...MAINTENANCE Figure 4 6 Clearing Tie Trunk Troubles Sheet 5 of 5 4 59 ...
Page 236: ...MAINTENANCE Figure 4 7 Clearing Paging Equipment Troubles ...
Page 250: ...MAINTENANCE Figure 4 9 System Cabinet Backplane Wiring Side Sheet 2 of 2 4 74 ...
Page 251: ...MAINTENANCE Figure 4 10 TDM Signal Designations on Cabinet Backplane 4 75 ...
Page 252: ...MAINTENANCE Figure 4 11 Power Designations on Cabinet Backplane 4 76 ...
Page 263: ...MAINTENANCE Figure 4 12 Clearing Virtual Facilities Troubles Sheet 1 of 3 ...
Page 264: ...MAINTENANCE Figure 4 12 Clearing Virtual Facilities Troubles Sheet 2 of 3 4 87 ...
Page 265: ...MAINTENANCE Figure 4 12 Clearing Virtual Facilities Troubles Sheet 3 of 3 4 88 ...
Page 271: ...MAINTENANCE Figure 4 13 Clearing Switched Loop Attendant Console Troubles Sheet 1 of 5 ...
Page 272: ...MAINTENANCE 4 13 Clearing Switched Loop 2 of 5 Console Troubles Sheet 4 95 ...
Page 273: ...MAINTENANCE Figure 4 13 Clearing Switched 3 of 5 Loop Attendant Console Troubles Sheet 4 96 ...
Page 274: ...MAINTENANCE 4 13 Clearing Switched 4 of 5 Console Troubles 4 97 ...
Page 321: ...APPENDIX E Administration Codes and Data This page is intentionally blank E 2 b ...