BT BT Versatility manual Cabling the unit, Connecting the extensions

BT Versatility

Installation and Maintenance Manual

Cabling the unit

All Line and Extension circuit cabling is inserted from the top of the unit. There are breakouts as shown on the top of the unit to facilitate routing of cables into the MDF area.

Cabling Break outs

Connecting the extensions

It is recommended that all extensions be cabled with 2 pairs. The Featurephones use all four wires and standard phones use the a,b pair only.

Do not exceed the following resistance or distance limits when connecting extensions to the System Unit. (The distances listed assume 0.5mm-tinned copper conductor is used).

•67 Ohms, or 400 metres, for system Featurephones.

•336 Ohms, or 2 kilometres, for a standard telephone

•336 Ohms, or 2 kilometres, for a standard telephone connected to the external extension on the Options Module

The Extension cables must be of twisted-pair construction, using insulated tinned copper wires of nominal 0.5 mm2 cross-sectional area. Category 5 cable must be used for all ISDN installations.

It is important that this size and type of wire is correct since incorrect types can result in unreliable connections. Care should be taken to ensure that the cabling complies with all relevant cabling requirements.

Run cable from each Extension location to the Main Equipment. Pass the cable through the cable entry hole in the CCU or Expansion Module and terminate the Extension wiring at the appropriate connector in accordance with the table below.

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