Table of contents 1. Introduction Revision History Document Release Information An Overview of the Maintenance Tasks How to Use this Guide Getting Ready 2. Routine Maintenance Servicing the Air Intake Filter Cleaning the Tape Heads of the Cartridge Tape Units 3.
However, the maintenance personnel may also be employees of the telephone company (if a leased system) or Northern Telecom, if a service contract is purchased from Northern Telecom.
2 Introduction Document Release Information The release information for this document is found on page i. The information includes the 10-digit identification number for the practice, plus the following additional information: Date: This is the date the document was released for reproduction or printing.
Introduction 3 How to Use this Guide To simplify the use of the document and to improve its readability, the tasks are described from the point of view of the maintenance personnel doing the actual work. There may, however, be more than one person using the procedures.
4 Introduction Getting Ready Before starting any maintenance or troubleshooting tasks, ensure that you have read the introduction of this document. Then, if you are going to install or remove equipment, you should review the appropriate supporting documents, such as the Installation Guide for Cabinet Systems, 450-1011-201, and the Guide to System Administrative Services, 450-1011-301.
2. Routine Maintenance The system is based on solid state circuitry that requires little routine maintenance. However, its efficient operation does depend on the periodic cleaning or replacement of the air filter in each cabinet and the tape heads of the cartridge tape units.
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6 Routine Maintenance Figure 2-1 The Air Intake Grill and Filter Filter Air Grill Practice 450-1011-501...
Routine Maintenance 7 You can now clean the filter with a vacuum or replace it with a new filter. Insert the new or cleaned filter into the filter slot and slide it in until the air grill can be freely closed. Close the air grill, snapping it into position.
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8 Routine Maintenance Figure 2-2 Tape Head Location in the Mass Storage or Cartridge Tape SRU Tape Slot Erase Head Select Read/Write Head Fault Direction of Cleaning Motion Practice 450-1011-501...
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Routine Maintenance 9 Figure 2-3 Tape Head Location in the 1/4-shelf Disk/Tape SRU Push this knob down to clean the tape heads The read/write heads are located behind this knob, close to the back of the slot. They are exposed slightly (for cleaning) when this knob is pushed down.
3. Troubleshooting and Fault Clearing Procedures Troubleshooting usually begins when someone, such as a user or the system administrator, notices a symptom of a fault. It may be that a piece of equipment is not functioning properly, an alarm has been generated, or the system has displayed a fault message on the notification line of the terminal screens or on the liquid crystal display (LCD) of the SASI Primary Processor.
12 Troubleshooting and Fault Clearing Procedures 450-1011-201. If a cabinet subassembly is faulty, remove it and install a spare according to Part 4 of this document. The Installation Guide for Cabinet Systems provides procedures for installing the following equipment: • cabinets •...
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Troubleshooting and Fault Clearing Procedures 13 For each device whose status is other than ‘Working’, invoke a ‘Courtesy Down’ function followed by a ‘Put Into Service’ to reboot that device. Note the following conditions: The rebooting function for software PRUs resident on an SRU may lag behind the rebooting function of the actual hardware SRU.
If the system fails to reboot successfully, power the system down, replace the Mass Storage SRU, format the disk, and again attempt to reload or rebuild the system. If you continue to have problems, contact Northern Telecom's customer service center. Rebooting the System Rebooting the system is a last-resort method of remedying an error condition.
Troubleshooting and Fault Clearing Procedures 15 Type in the command :LOCAL:UUTILS:SOFTBOOT (in capital letters, lowercase letters, or a mixture), and then press ENTER. The system prompts you to specify whether you want to quit the program, reboot immediately, or reboot after a delay. To reboot immediately, follow Step 6.
16 Troubleshooting and Fault Clearing Procedures Figure 3-1 Primary Processor XP 68020-7, with Reset Switch Reset Switch (Other Switches Are for Future Use) . . . 25-Pin RS-232-C ....
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Troubleshooting and Fault Clearing Procedures 17 Table 3-A Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS SAS PROBLEMS/SYSTEM REBOOT PROBLEMS System Administrative Another user is using SAS. Try again when no one else is using Services is unable to start. Only one user at a time is SAS.
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18 Troubleshooting and Fault Clearing Procedures Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS The Power Supply SRU is equipped with a power-on LED indicator built into the circuit breaker on the front panel. The breaker is intended to trip if an overcurrent condition occurs (10 A). The Loft Power Supply (one per cabinet) is fused for protection against over-voltage conditions.
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Troubleshooting and Fault Clearing Procedures 19 Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS In systems powered by the The circuit breaker on one or Power the system down, reset the Power Supply SRUs, the more Power Supply SRUs is circuit breakers by pressing ‘1’...
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20 Troubleshooting and Fault Clearing Procedures Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS PRIMARY PROCESSOR FAULTS With the power on, the liquid The Primary Processor SRU is Power the system down and crystal display on a SASI not properly seated.
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Troubleshooting and Fault Clearing Procedures 21 Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS There is a cabling fault Power the system down. between the Primary Check that the cable is free of Processor SRU and the shorts, open or broken wires, and Mass Storage SRU.
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22 Troubleshooting and Fault Clearing Procedures Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS CARTRIDGE TAPE UNIT FAULTS With the power on, the liquid There is a cabling fault Power the system down. crystal display on a Primary between the Primary Check that the cable is free of...
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Troubleshooting and Fault Clearing Procedures 23 Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS WARNING: Mass Storage SRUs are very heavy. M4000 TERMINAL FAULTS The terminal does not display There is a power fault. Clear the power fault.
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24 Troubleshooting and Fault Clearing Procedures Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS Frozen displays on all the There is a LANlink fault. Investigate the LANlink SRU. (See M4000-series terminals LANLINK FAULTS, later in this connected to a LANlink SRU.
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Troubleshooting and Fault Clearing Procedures 25 Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS The modem's internal In the batch configuration file, the configuration is not correct for port is defined as an ATA port. the LIU port.
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26 Troubleshooting and Fault Clearing Procedures Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS The LIU port used by the Ensure that the LIU port used by the ASCII terminal is not properly ASCII terminal is defined as an ATA defined in the batch port in the batch configuration file.
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Troubleshooting and Fault Clearing Procedures 27 Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS PRINTER FAULTS The Log printer or the The printer is off line. Put the printer on line. Reports printer is not working. There is a paper fault: check Clear the paper jam or insert paper, for a paper jam or an...
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28 Troubleshooting and Fault Clearing Procedures Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS The cable connections to the Change the cabling to conform to LANlink line and the LIU port the configuration. do not conform to the system configuration.
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Troubleshooting and Fault Clearing Procedures 29 Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS The LANlink does not Sign on as a System Administrator conform to the system map. and check that the LANlink SRU's location in the system map matches the physical location.
30 Troubleshooting and Fault Clearing Procedures Table 3-A Continued Summary of Fault Symptoms and Potential Solutions SYMPTOMS PROBABLE CAUSES CORRECTIVE ACTIONS Normally, the PRU goes from the ‘Preload’ state to ‘Loading’, and then to ‘Working’. If the PRU goes quickly from ‘Preload’...
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Troubleshooting and Fault Clearing Procedures 31 The information displayed identifies the unit by its communications address, type, and name. It also shows its status and, if a PRU, its software revision number. If there are no faulty units, the display is blank.
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32 Troubleshooting and Fault Clearing Procedures To check the status of SRUs in cabinet 2, press <Next Cabinet>. You can page forwards and backwards through the cabinets using <Next Cabinet> and <Previous Cabinet>. From any of the Cabinet screen displays, you can move to a lower level in the screen hierarchy to view the status of each PRU in a selected processor SRU, or the equipment connected to each port of a LANlink SRU.
4. Replacing Cabinet Subassemblies Equipment installation and removal instructions are provided in detail in the Installation Guide for Cabinet Systems, 450-1011-201. However, exceptions are cabinet subassemblies, such as the fans and filter doors. These subassemblies should be removed only under the terms and conditions of your maintenance agreement with your supplier.
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34 Replacing Cabinet Subassemblies To remove a fan, proceed as follows: - WARNING - For your protection and the protection of the equipment, make sure the system is powered off for this procedure. Open the rear door of the cabinet and use a 5/16-inch Allen wrench to remove the hinge plate from the bottom of the door as shown in Fig.
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Replacing Cabinet Subassemblies 35 Figure 4-1 Removing the Rear Door and Fan Assembly from the Cabinet Practice 450-1011-501...
36 Replacing Cabinet Subassemblies Installing the Fan Assembly To keep the system operational while a faulty fan unit is being repaired, you should install a spare. When the faulty fan is returned from the repair depot, it should be stored as the spare. Ensure that the replacement unit has the same part number as the unit being replaced.
Replacing Cabinet Subassemblies 37 (11) Verify that the door opens and closes smoothly. If not, loosen the fan grill mounting bracket and move it slightly forward or backward to adjust the door. Replacing the Filter Door With proper handling when cleaning or replacing the cabinet filter, the fan filter door at the bottom of the cabinet should not be damaged.
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38 Replacing Cabinet Subassemblies Figure 4-2 Replacing the Filter Door Filter Air Grill Practice 450-1011-501...
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