NEC Neax 2400 Imx System Operations And Maintenance Manual
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CHAPTER 2 NDA-24238 Pag e 2 4 Revision 3.0 SYSTEM MAINTENANCE OUTLINE Figure 2-18 Speech Path Range of Fault MUX A fault within this range affects this module. 32ch A fault within this range affects the circuit card.A fault within this range affects two slots. PIM 3 A fault within this range affects this module. 32ch A fault within this range affects the circuit card.A fault within this range affects two slots. PIM 2 A fault within this range affects this module. 32ch A fault within this range affects the circuit card.A fault within this range affects two slots. PIM 1 A fault within this range affects this module. 32ch A fault within this range affects the circuit card.A fault within this range affects two slots. PIM 0 TSW TSW/INT512ch 512ch 512ch 512ch LC/TRK LC/TRK MUX MUX MUX LC/TRK LC/TRK LC/TRK LC/TRK LC/TRK LC/TRK : Circuit Card : Possible fault range to be affected : Speech Path Symbols
NDA-24238 CHAPTER 2 Page 25 Revision 3.0 SYSTEM MAINTENANCE OUTLINE 2.7 Explanation of Terms C-Level Infinite Loop The program repeatedly executes specific routines due to a fault of the main memory, data destruction, etc. The program is not able to be processed normally. This faulty condition is referred to as Program Infinite Loop. C-Level infinite loop is a state where a clock-level program, which runs under clock interrupt disable state, is in an infinite loop status. B-Level Infinite Loop This is a state where a program infinite loop has occurred during a connection processing and the con- nection for the next call is not able to be processed. Port Microprocessor (PM) Each line/trunk card mounted in the PIM is equipped with a processor called Port Microprocessor (PM), which continuously supervises the lines/trunks. Ready Error For acknowledging the connection between the CPU and a circuit card, an interface signal called Ready Signal is used. When the CPU has accessed a specific circuit card and the normality of the con- nection is acknowledged, the Ready Signal is returned to the CPU within 6 µs. If the Ready signal is not returned to the CPU within 6 µs after access, the situation is referred to as Ready Error. Parity Error For confirming the normality of data transfer between the CPU and the circuit card under the control of the CPU, parity check is made. When an error is detected in a parity check, it is referred to as Parity Error. Parity check means to confirm the normality of data by adding an error detecting parity bit to a set of data to be transferred. When a set of data is transferred, a parity bit is added to the data so that the data has an even-number of “1” bits (it is referred to as Even Parity). When there is an odd-number of “1” bits in the received one set of data, it is detected as an error. Monitor Restart Monitor restart processing suspends current processings in progress without applying any hardware controlling, allowing the system to restart its operations from the monitor program. The system abandons only the processings of the calls being handled by the program, and maintains all the connections that have already been established. Circuit Card Front Initializing Restart The whole system is forcibly initialized. However, the initialization varies with the setting of the SENSE switch on the DSP of CPU (see Table 2-2).
CHAPTER 2 NDA-24238 Pag e 2 6 Revision 3.0 SYSTEM MAINTENANCE OUTLINE PM (Line/Trunk Card) Make-Busy Restart In this processing, the faulty PM (Line/Trunk Card) is isolated from the system and, at the same time, the calls associated with that faulty PM (Line/Trunk Card) are released. No calls related to the faulty PM (Line/Trunk Card) are processed and the system normally runs without the faulty PM (Line/Trunk Card). Data Copy Restart In a system of dual CPU configuration, the RAM memory (including the data memory) is copied from the ACT side CPU into the STBY side CPU, and ACT/STBY is changed over and monitor restart is executed. In the case of this restart processing, only the ACT side CPU and the STBY side CPU are changed over without any effect on the current connections. However, no call processings are executed while the restart processing is in progress (from copying until the end of the changeover). 3. HOW TO READ PRECAUTIONS, DIAGNOSTIC, AND FAULT REPAIR INFORMATION 3.1 Precaution about Diagnostic Procedure/Fault Repair Procedure When performing diagnostic procedures/fault repair procedures, always adhere to the following actions: (1) When replacing a circuit card with a spare, handle the circuit card using the Field Service Kit. (a) To protect the circuit card from static electricity, wear a wrist strap before handling the circuit card. (b) Before extracting the circuit card from its mounting slot, set its MB switch to the UP side (ON). (2) When holding a circuit card by hand, wear gloves and be careful not to touch mounted parts, gold-plated terminal, etc., on the circuit card. The 3M Model 8012 Portable Field Service Kit, shown in Figure 2-19, is recommended as an effective countermeasure against static electricity. Table 2-2 Kinds of Circuit Card Front Restart SENSE (0~F) KIND OF RESTART REMARKS 1 DM Clear Restart 2 DM Load Restart When the system is in operation 5 OAI Memory Clear Restart C OFF-line Restart
NDA-24238 CHAPTER 2 Page 27 Revision 3.0 SYSTEM MAINTENANCE OUTLINE Figure 2-19 3M ® Model 8012 Portable Field Service Kit Figure 2-20 How to Hold a Circuit Card Wrist StrapPlace the Circuit Card on a conductive sheet. Connect ground wire to the Earth terminal of the Module Group. Note:3M is a registered trademark of Minnesota Mining and Manufacturing, Inc. 12 34 OFF12 34 567 8 OFF 12 34 5 67 8 OFF 12 34 5 67 8 OFF 12 34 5 67 8 OFF 12 34 OFF 12 34 OFF 12 34 567 8 OFF12 34 5 67 8 OFF12 34 5 67 8 OFF 12 34 5 67 8 OFF Card Puller Tab Circuit Card Circuit Card Plastic BagGold Plated Terminal Note Note:Do not touch the Gold-Plated Terminal with bare hands.
CHAPTER 2 NDA-24238 Pag e 2 8 Revision 3.0 SYSTEM MAINTENANCE OUTLINE (3) When a circuit card appears to be faulty, check the following items before replacing it with a spare: (a) Poor connector contact at the circuit card may be responsible for the fault. Repeat insertion and ex- traction of the circuit card a few times. Clean the connector portion, and recheck for proper operation. (b) Check the lead wires of vertically-mounted parts (resistors, capacitors, etc.) to ensure they have not shorted each other or broken. (c) Check the back side of the circuit card to see if there is any short-circuited soldered portion, or mod- ified cross connection wires erroneously left unconnected. (d) Check the ROMs to ensure proper seating in the IC socket. Figure 2-21 shows a leg that is bent and not set in the socket. Figure 2-21 How to Set the ROM in IC Socket A pin is bent, not inserted in the socket. ROM SOCKET
NDA-24238 CHAPTER 2 Page 29 Revision 3.0 SYSTEM MAINTENANCE OUTLINE (4) How to clean the connector portion (gold-plated terminal): (a) Dip the gold-plated terminal portion in the cleaning fluid for 3 to 5 seconds (only PA-XX type circuit card), as shown in Figure 2-22. Figure 2-22 How to Clean the Connector Portion Note 1: Some of the parts are subject to damage if they come in contact with the cleansing liquid. Be careful to allow only the connector portion (gold-plated terminal) to contact the cleaning liquid. Note 2:Be sure to use fresh cleaning fluid (FREON or isopropyl alcohol). (b) Using a soft cotton cloth, wipe both sides of the connector portion (gold-plated terminal) clean (only PA-XX type circuit card), as shown in Figure 2-23. Figure 2-23 How to Clean Gold-Plated Terminal Note 1: Use cloth (gauze, etc.) to clean. Note 2:After wiping, be careful not to leave lint on the surface of the circuit card. (5) When a check on the flat cable or LT cable is directed in the tree, check the following items: (a) Make a visual check to see if the connector is properly connected. (b) Poor connector contact may be responsible for the fault. Repeat connection and disconnection a few times, and check again to see if the connector is properly connected. (c) Perform continuity test on the flat cable. (6) When replacing the circuit card is directed in the tree, replace the circuit card with a spare as per Chapter 4. (7) When multiple circuit cards appear to be faulty, before replacing them with spares, remount them (one at a time) into their slots, to determine which cards should be replaced. Cleaning Fluid Circuit Card Container gauze Gold-plated terminal
CHAPTER 2 NDA-24238 Pag e 3 0 Revision 3.0 SYSTEM MAINTENANCE OUTLINE The following is an example where the fault was recovered after the replacement of circuit cards: (8) When a fault recovery is completed, use the RALM command to clear all the alarm indications and reg- istered system messages. If required, restore temporary cross connections and transient data for testing to the original ones. 3.2 How to Follow Diagnostic Procedure/Fault Repair Procedure (a) Diagnostic Work A fault diagnostic procedure by system message is explained in the “TREE” format on an individual system message basis. Proceed with judgment as to whether the fault status coincides with the indicated status, following the sequence beginning from START. How to proceed with the diagnosis work is explained in Figure 2-24. STEP 1 Determine whether the fault coincides with the fault status (1) in Figure 2-24. STEP 2 If the fault status does coincide, the fault is indicated by (2). Repair the fault by referring to the relevant section in Chapter 5. Otherwise, proceed to (3). STEP 3 Perform the work indicated by (3). The result of the work (3) is broken down as indicated by (4). STEP 4 Determine whether the result of work (3) coincides with the status indicated by (5). If so, the fault(s) is/are indicated either by (6) or by (7). If not, proceed to the next Step. Set the 1st circuit card back into its mounting slot If the fault recurs: Replace the circuit card. Set the 2nd circuit card back into its mounting slot If the fault recurs: Replace the circuit card. Set the 3rd circuit card back into its mounting slot If the fault recurs: Replace the circuit card. If a circuit card is found to be faulty, send the faulty circuit card for repair. The fault may be a temporary one, or due to poor contact of the circuit card. Observe the situation for a while. START END
NDA-24238 CHAPTER 2 Page 31 Revision 3.0 SYSTEM MAINTENANCE OUTLINE STEP 5 Perform the work indicated by (8), and if the result of the work is the same as the status indi- cated, the fault is indicated by (9). If the fault repair work indicated by (9) affects another nor- mal line, recheck the work as indicated by (10). (b) Fault Repair Procedure A fault repair procedure is explained by means of “TREE” format in Chapter 5. The following ex- plains how to follow the “TREE” format and proceed with designated work. See Figure 2-25. Begin from START and proceed with the necessary repair work following the sequence. When a faulty circuit card (or circuit cards) is suspected, replace the faulty circuit card with a spare in accordance with the work procedure pertaining to that specific circuit card. STEP 1 Replace the circuit card indicated by (A) with a spare and check it. Perform the detailed work as per (B). If the fault status is beyond repair, proceed to the next step. STEP 2 If the range of the fault or the system configuration is as indicated by (C), perform a check as indicated by (D). If the fault status is beyond repair, proceed to the next step. STEP 3 Replace the circuit card indicated by (E) with a spare and check it. The detailed procedure in- dicated by (G) varies with the system configuration indicated by (F).
CHAPTER 2 NDA-24238 Pag e 3 2 Revision 3.0 SYSTEM MAINTENANCE OUTLINE Figure 2-24 Diagnostic Work Items and Symbols Example FAULT SUPERVISION START END WhenFAULT Section No. (1) : It is the fault of Perform(3) (4) When (5) (2) WhenFAULT Section No. : It is the fault of (7) When(8)with performed FAULT Section No. : (9) CHECK OF WORK (6) (10) (11) (Chapter 5) (Chapter 5)(Chapter 5) (11) (5) Note:(1): Judgment of fault status (2),(6),(7),(9): When the fault status coincides with the indication, the cause of the fault is indicated. (11): When repairing the fault, refer to the relevant section in Chapter 5. (3): Operating items for diagnosis (4): Branching of the result of the operation (5): Judgment of the status of the result of the operation (8): When operating method is unknown, refer to Chapter 6. (11)
NDA-24238 CHAPTER 2 Page 33 Revision 3.0 SYSTEM MAINTENANCE OUTLINE Figure 2-25 Recovery Procedure Example 4. REPORTING FAULT TO NEC When the cause of a fault is uncertain, make note of the situation involved and report it to NEC. When for- warding faulty circuit cards to NEC, exercise caution to protect from static electricity. 4.1 Fault Reporting Method The following three items must be included in the report without fail: (1) Faulty situation (reports should be similar to “dial tone is not heard only on individual lines,” “incoming C.O. line calls are not able to be terminated only to a specific ATTCON/DESKCON,” etc.) Faulty phenomena On lifting the handset, dial tone is not heard but side tone is heard, etc. START END Check(A) (B) When(C) (D) When(F) (G) Check Check(E) When (G)(F)