Telos NX12 Troubleshooting Desktop Director Problems, Replaceable Modules and Hardware Servicing

Technical data & troubleshooting  81

to turn on ISDN logging.

6.5 Troubleshooting Desktop Director Problems

Most problems with the Desktop Directors are cable related. First try a new cable. If that fails to solve the problem, try the Desktop Director with a short cable plugged directly into each of the Director Ports on the back of the Nx12.

Note that early production Call Controllers require a modification to operate with the Nx12. Telos customer support can arrange for modification of these units at no charge.

Section 2 has details on the allowable wiring configurations for the Desktop Directors and other control surfaces. There are distance and wiring restrictions. Note that when two Directors share a single port an external power supply is required and the termination resistor must be removed on the unit closer to the power supply.

The diagnostics on the Desktop Director and the Nx12’s status screen will help isolate bad wir- ing or hardware. If errors are accruing try systematically swapping ports, and swapping Desktop Directors, to see if the problem stays with a given port, Desktop Director, or cable.

6.6 Replaceable Modules and Hardware Servicing

WARNING - DANGER

Remove all connections, including the Telephone, Audio, and Electrical Mains Power cord before opening the unit. Failure to do so could result in injury or death. Do not open the unit unless you are qualified to do so.

Removal of the top plate gains access for service. To do so, remove the 10 Philips head screws.

Replaceable modules

While we do not expect you to do much repair or troubleshooting of the individual circuit boards, the system does have several removable modules which can be replaced. The system has the following replaceable modules:

1.Power Supply

2.ISDN Line interface card:

Part # 1701-00140 (U interface - USA and Canada); or Part # 1701-00139 (S interface – Worldwide)

3.Analog POTS Line Interface part # 1701-00141

4.AES option card part # 1701-00149

Fuse Replacement

A fuse is located on the power supply PCB. If fuse replacement is required, note: For continued protection against fire, replace fuse only with same type and value.

Access to the Main PCB

The main PCB, closest to the bottom of the enclosure, is mounted component-side down. You can gain access to the component side of the PCB without taking it out by removing the bottom plate of the enclosure box.