Reason for revision 91 03 08 This procedure was reissued to include information on the Japan Digital Multiplex Interface (JDMI) for GenericX11 including supplementary features. It has been reformatted for CD-ROM application 553-2911-510 2 Mb/s DTI Fault Clearing Procedures...
General This manual describes the maintenance procedures for the Meridian SL- 2 Mb/s Digital Trunk Interface (DTI) and Japan Digital Multiplex Interface (JDMI) for GenericX11 including supplementary features. This manual is divided into two chapters. The first chapter contains step- by-step instructions on how to analyze a trouble.
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1-2 General Figure 1-1 (continued) Flowchart symbols Decision block - contains a question. The answer indicates the path to follow. Continuation symbol - contains the location of the next step Stop symbol - identifies the end of a procedure 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Answer this question.
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Figure 1-1 (continued) Flowchart symbols AND symbol - groups a sequence of steps, ALL of which must be performed to achieve a result. Perform this ( 1 ) step, and Perform this ( 2 ) step. OR symbol - groups a sequence of steps, only ONE of which must be performed to achieve a result.
Trouble analyzing procedures Alarm Lamps (LEDS) This section contains detailed step-by-step instructions on how to analyse a trouble (with reference to Detailed Procedures, where required) Out of Service (OOS) Alarm LED Lit If either the Near-end alarm (NEA) or Far-end alarm (FEA) LED is also lit, then perform that procedure (i.e., NEA or FEA) before attempting this procedure.
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2 - 2 Trouble analyzing procedures 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 status. Is the DTI2 pack out of service due to error counts being exceeded? Disable the DTI2 pack. Run DTI2 self test. (Chart 3-4) Is the OOS LED out? Unseat the DTI2 pack.
Far-end Alarm (FEA) LED Lit DTI2 far-end alarm LED is lit. Load overlay 60. Check the DTI2 pack status, then disable the DTI2 pack and run DTI2 self test (Chart 3–4). Is the DT12 pack Disable the DTI2 pack and connect the loopback plug to the DTI2 faceplate (Chart 3–3).
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2 - 4 Trouble analyzing procedures 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Does the FEA LED remain out? Disable the DTI2 pack. At the Office Repeater Bay or the main cross connect terminal, loopback the 2 Mb/s signal to the DTI2. Enable the DTI2 pack.
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Is signal present? Connect line monitor to the Receive pair test jack (Rx-D) at Office Repeater Bay or Multiplexer. Is signal present? Restore cabling to normal. The problemis most likely with Receive cabling between the Office Repeater Bay and the DTI2 pack.
2 - 6 Trouble analyzing procedures Near-end Alarm (NEA) LED Lit DTI2 near-end alarm LED is lit Load overlay 60. Check the DTI2 pack status, then disable the pack and check the error counts. Are any of the error thresholds exceeded? Disable the DTI2 pack and run DTI2 self test (Chart 3-4).
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Is the DTI2 pack Disable the DTI2 pack. Remove the carrier cable and install the loopback plug (Chart 3-3). Reset the error counters and enable the DTI2 pack. Does the NEA LED remain out? Disable the DTI2 pack. Restore the cabling. At the Office Repeater Bay, connect the line monitor to the receive...
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2 - 8 Trouble analyzing procedures 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Is the signal present? Restore cabling to normal. Problem is likely with Receive cabling pair between the Office Repeater Bay and the DTI2 pack (Rx-D to Rx-A). Restore cabling to normal.
Loopback Alarm LED Lit DTI2 loopback LED is lit Load overlay 60. Check the DTI2 pack status. Are any of the channels or the DTI2 pack itself in loopback? Disable the DTI2 pack and run the DTI2 self test (Chart 3-4). Page 2-10 Trouble analyzing procedures Remove the channel/DTI2...
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2-10 Trouble analyzing procedures 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Is the LED off? Disable the DTI2 pack. Unseat the pack from the back panel, then re-install. Do all the LEDs flash on and off? Chart 3-1 Enable the DTI2 pack. Enable the DTI2 pack.
Disable (DIS) Alarm LED Lit DTI2 Pack DIS LED is lit. Are any other LEDs lit? Load overlay 60. Run the DTI2 self test (Chart 3-4). Is the DTI2 pack Step 7 Page 2-12 Trouble analyzing procedures 2-11 Refer to: Page 2-1 (for OOS), Page 2-3 (for FEA), Page 2-6 (for NEA),...
2-12 Trouble analyzing procedures Violation Error Messages Note: • Bipolar Violation Error: DTAXXX L BV • Coded Mark Inversion Violation Error: DTAXXX L CV 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Replace the DTI2 pack (Chart 3-1). Error Message Formats: Violation Error message: where XXX is 210, 211, 212,...
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Signal present? Using line monitor (Chart 3-3), monitor RECEIVE pair at the DTI2 pack (Rx-A). Signal present? Disable DTI2. Clear error counts. Remove carrier cable and install loopback plug (Chart 3-3). Enable DTI2. Step 10 Page 2-14 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Trouble analyzing procedures Suspect problem with carrier or the far end.
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2 - 1 4 Trouble analyzing procedures 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Are the BPV counts increasing? Replace the DTI2 pack (Chart 3-4). Suspect problem with the carrier or the far-end.
SL-1 a Master in the synch hierarchy? Both packs OK? Step 7 Page 2-12 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Trouble analyzing procedures Far End is not locked to this Meridian SL-1. Replace faulty pack (Chart 3-1/Chart 3-2). 2-15...
Frame Alignment Error Message Frame Alignment Error message: DTAXXX L FV on TTY, where XXX is 210, 211, 212, 216, 217 or 218 and L is the loop number. Using line monitor (Chart 3-3), monitor RECEIVE pair at the office repeater bay (Rx-D).
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2-18 Trouble analyzing procedures 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 Is the signal present? Disable the DTI2 loop and run the self test (Chart 3-4) Is the DTI2 pack Fault possibly with the Receive pair between the main cross- connect terminal and the DTI2 pack.
DTI2/DMI Pack Replacement Chart 3-1 Replacement of Digital Interface circuit pack Firmly touch the metal frame of the cabinet to discharge static electricity from your body before handling circuit packs Step Pack Removal: Installation CAUTION P r o c e d u r e Disable the Network Loop, using Overlay 60.
3 - 2 Replacement, Monitor and Test procedures Chart 3-1 (continued) Replacement of Digital Interface circuit pack Step Clock Controller pack replacement C h a r t 3 - 2 Replacement of Clock Controller circuit pack Note: Do not deviate from this procedure. This procedure will not cause Firmly touch the metal frame of the cabinet to discharge static electricity from your body before handling circuit packs 2 Mb/s DTI Fault Clearing Procedures 553-2911-510...
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3 - 4 Replacement, Monitor and Test procedures Chart 3-2 (continued) Replacement of Clock Controller circuit pack Step 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 P r o c e d u r e Ensure that the Clock Controller card being replaced is associated with the inactive CPU.
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Replacement, Monitor and Test procedures 3 - 5 Use Overlay 60 to verify normal service level. First; switch the active clock to standby. The command is SWCK 'n'. Next; check the status of the new Clock Controller. The command is SSCK 'n'. If a trouble is indicated by the response, refer to NTP 553-2301-511 for an interpretation of the message.
3 - 6 Replacement, Monitor and Test procedures 2.048 Megabit PCM line monitor C h a r t 3 - 3 2.048 Megabit PCM line monitor Step 2 Mb/s DTI Fault Clearing Procedures 553-2911-510 P r o c e d u r e To monitor the DTI 2.048 Mb/s pcm data stream, use: SIGNAL MONITOR, •...
Verification tests for DTI2/DMI and CC packs C h a r t 3 - 4 V e r i f i c a t i o n t e s t s f o r D T I 2 / D M I a n d C C p a c k s Verification test for DTI circuit pack Step 2.
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