BusinessPhone Communication Platform 7.0
Fault Tracing

## General

These fault locating instructions shall serve as a guide for servicing an ASB 150 02 telephone exchange (PBX). This document presupposes that all installation and start-of-operation instructions have been adhered to. This document covers only such faults (errors) as equipment malfunctions or some incorrect programming. When beginning start by classifying the fault type (see Fault locating).

Generally, when servicing a PBX a hardware fault can only be remedied by replacing the faulty hardware on site and the faulty unit(s) are to be returned to the supplier with a claim for compensation. No repairs are to be done in the field.

The PBX has operation and maintenance programs installed which can be accessed via the BusinessPhone Management Suit (BMS). The BMS server can be situated either in a remote service centre or locally at customers site.

The service personnel shall be familiar with the system, in particular regarding BMS and with its possibilities, as BMS is the best fault locating aid.

### Tools for fault locating

Fault locating from an operation and maintenance (O&M) centre requires a BMS server and a Hayes-compatible V.32bis modem.

Fault locating on site requires a (portable) PC with BMS and a V.24-cable connected to a free V.24-port. Additionally required tools are: a voltmeter (DVM), a system telephone, board extractor and a set of screwdrivers. As the boards are sensitive to electrostatic discharges please use a grounding wrist strap correctly connected to ground when handling the boards.

The BMS contains also functions for Cordless System part regarding initialization, system maintenance and updating, system fault finding and repair. As BMS configuration past cannot detect IC-LU boards installed in the system it is advisable to locate these boards to the right of the IC-CU_ board.

The Cordless System Statistics is also included in BMS. It collects and interprets statistical information from the Cordless System. It gives an overview of the traffic load of the total Cordless System, load per Base Station or per portable telephone. Important data of telephone calls are stored, for example the duration of calls, the number of hand over and errors like failed calls or portable telephones that could not be reached.

If BusinessPhone is equipped with an IC‑CU board, then the Cordless System Manager Software has to be used for the Cordless System part regarding initialization, system maintenance and updating, system fault finding and repair.

### Replacement of printed board assemblies

Before handling printed board assemblies (PBAs) service personnel shall always connect themselves to ground to prevent damage caused by static discharges.

Note

Boards with Electrostatic Sensitive Devices (ESD) are marked with sign.
In the interest of quality and reliability of the system boards, always handle static sensitive boards with special care. Always use a wrist strap connected to a low resistance ground e.g. provided on the cabinet:
Use portable equipment LYA 30101 as a protection against electrostatic discharges.

Some of the benefits of ESD protection are:

- less failures/service calls
- lower maintenance costs
- higher customer satisfaction

Older system versions of the PBX must be restarted (e.g. switched OFF and ON) after the replacement has taken place. Boards of ASB 150 02 R10 or higer can be replaced during power on. The board can be exchanged during operation by a board with the same type and number of individuals. Since ASB 150 02 R13 it is possible to modify the peripheral board functions. For details concerning modification of boardfunctions please refer to fMaintenance Instruction ASB 150 02 (1541-ASB 150 02 Uen). Prior to removing the board, it can be disabled for traffic (by BMS) and the new board is put in operation without the need of restarting the exchange. A new board can be inserted in a free slot and put in operation. When replacing boards be careful when inserting the board in the cabinet as not to damage the backplane connector (e.g. bending pins due to misalignment) or to cause a short circuit on the layer side of neighbouring boards e.g. by elevated components such as transformers, capacitors.

Note

The PBX will generate warnings to this effect and is therefore advisable to read the relevant warning log. Also bear in mind that restarts normally generate the alarm and if automatic alarm transmission is active, alarms will be generated to the relevant alarm centre. This can be avoided by re‑classifying the restart codes or by deactivating the alarm transmission.

The changes done to avoid alarms from being issued while servicing shall be reset after final restart has been effected and the system handed over to the customer.

The procedure for replacement of boards is described below:

1. Transfer the (if any) warning log to a file in BMS if possible for later evaluation and appropriate measures. Make a printout of the warning log.
2. Deactivate active alarm.
3. With BMS save configuration data if possible when CPU-D_ is to be replaced or make a backup of the Cordless data if the failure concerns the IC-CU_ or IC-LU.
4. Connect portable equipment LYA 30101 to protect against static electricity.
5. Replace faulty PBA.
6. Older system versions of the PBX (prior to ASB 150 02 R10): Restart PBX manually (switch power off and on) or via BMS. If the PBX comprises several cabinets the cabinet containing the CPU-D_ shall be switched ON as last.
7. Empty the warning log.
8. Reset active alarm if this is required.
9. When replacing the CPU-D_ perform a cold-start in the PBX and update it with the saved configuration data from BMS in order to restart all programmable data.

### Definitions

#### Blocked Printed Board Assembly (PBA)

A blocked PBA is normally unable to process traffic. The state of the board is indicated on the board's LEDs (see LED indications on the PBAs) and read outs of revision (R)-states is made via BMS where the board position is indicated (marked).

See BMS-menu: Boards

#### Blocked directory number

An individual whose directory number has been blocked cannot generate nor receive traffic. A blocked directory is not indicated on the LEDs of the device board. See BMS-menu CONFIGURATION.

#### Cold start

Cold start denotes a restart of the PBX, whereby all programmed data is erased and replaced by default values initially assigned e.g. factory.

Cold start is performed by placing a strap in the socket provided for this purpose on the front of CPU-D_ (see LED indications on the PBAs) and thereafter switching off and on the DC supply voltage to the cabinet containing CPU-D_. Instead of switching the PBX OFF and ON again two pins are available in connector field 2 on the CPU-D_ which can be short circuited by a plug to invoke restart (refer to System reset).

#### CPU

The central processor unit and its programs.

#### Device

The PBX can be considered as an interworking unit of function blocks. Such a function block is sometimes called a "device".

Examples of devices are: switch, tone sender, extension, trunk, MFC-register and voice memory.

The placing of the devices on PBAs is arbitrary.

#### Facility

The functions of a telephone exchange are called facilities. Often a facility consists of several connection cases. A connection case is initiated by means of a certain procedure from a telephone or other unit (equipment) connected to the exchange.

Examples of facilities are: internal call, external call, inquiry, transfer, intrusion, conference, sector paging, various types of diversion, programming of function keys and abbreviated numbers.

#### Hot swapping

A board of the PBX can be exchanged during operation by a board of the same type and with the same number of individuals. The board can be disabled for traffic (by BMS) prior unplugging it and the new board is put in operation without the need of restarting the exchange. A new board can be inserted in a free slot and put in operation.

#### Individual

An individual member (unit) of a group. The PBX possesses, among others, groups of extensions where an individual can connect a telephone.

On analogue trunks each individual can connect (is connected) to a trunk.

On digital trunks several individuals share a single line (cable/interface).

#### Installed PBA

A PBA is correctly installed if it is physically mounted in a board position stipulated in the appropriate installation instructions. A correctly installed PBA is a prerequisite for traffic.

See the guide text for RASC-menu MAINTENANCE-HW/SP-RP.

The LEDs on the board identify different board conditions. An explanation of the conditions is given under Fault locating.

#### Line network with stubs

Extension line with extra jacks in the form of a star network. See figure below.

#### Line signalling diagram with line test

Several line signalling diagrams for trunks include a line test that is done for both outgoing and incoming calls. These tests are described in BMS, BMS-menu CONFIGURATION-TRUNKS.

#### Link supervision

Digital trunks are supervised by the exchange and the state conditions, errors on the digital link to the public exchange are monitored. The monitoring data can be read out via BMS-menu maintenance-system-link supervisor and stored in a file or printed out.

#### Minimum system size

A minimum system comprises one cabinet equipped a CPU-D_ and either one ELU-D, ELU-C or ELU-A.

#### Power supply

Transformers, battery chargers, batteries and appurtenant cables are all included in the concept "Power supply".

#### Programmable parameters

The PBX possesses a considerable number of programmable parameters, which help O&M-personnel to adapt the function of the PBX to customer requirements. The majority of facilities and individuals can be programmed. See BMS-menu CONFIGURATION and the Cordless System Manager Software.

#### Recommended measure

Each warning code is described in BMS and recommended measures are offered.

See item Warning below.

#### Remote SW upgrading

The system software can be downloaded from a remote maintenance centre. Setting a certain time and date automatically loads the new software into the system non volatile memory and re-starts the exchange.

#### RP (Regional Processor)

The control system of the PBX is handled by a central processor and a number of regional processors. A typical task for an RP is to handle the hardware check on the individuals on a PBA.

#### Update board position

The database contains, among other things, relevant data for all board (PBA) positions in the PBX. The database contains also details about the type of PBA that should be installed.

The update means that the database is adapted to physical reality. An update is required in conjunction with a configuration change of the PBX, e.g. on expansion with new PBAs, on removal of PBAs and when a PBA is replaced by a different type of PBA.

See BMS-menu: boards

#### Warm start

Restart of a PBX with no cold start strap installed. This is the normal procedure in conjunction with power-up or controlled restart via BMS-menu Maintenance-log-reset.

All programmed data is retained.

#### Warning

The control system of the PBX is structured so that warnings are generated when abnormal situations occur. The warnings can be read out by O&M-personnel and also personnel who have access to the control system's source code.

Warnings that are directed to O&M-personnel are complemented with a recommended measure.

Warnings without recommended measures shall be interpreted by persons with access to the control system's source code.

Revision: K © Ericsson Enterprise 2005