General
Compatibility	COMpact 3000 analog, ISDN, VoIP
Number of internal S0 ports	1
Connection type	S0 (4-wire), UP0 (2-wire)
Connection options	Screw terminals, RJ45 socket
Maximum number of connected telephones	2
Range of internal S0 port	ca. 150 m
Technology	PTMP, Euro-ISDN, DSS-1
Form factor	Plug-in module
Number of connections	1
Compatible slots	1 expansion connector

The Auerswald COMpact S0 module is an expansion module for the COMpact 3000 series, extending the telephone system with an additional internal S0 port. It is compatible with the variants COMpact 3000 analog, 3000 ISDN, and 3000 VoIP, and serves to integrate COMfortel series system telephones into the existing network. The module enables the use of an internal S0 connection (Point-to-Multipoint, PTMP) within the local network, allowing up to two COMfortel system telephones to be connected. The connection is made via screw terminals or an RJ45 socket, enabling flexible installation in existing systems.

Applications
This module is primarily used for internal operations to extend existing telephone systems with additional devices. It is particularly suitable when an analog telephone line is to be used for modern system telephones, as it supports the S0 (4-wire) connection type. The range of the internal S0 port is approximately 150 meters, enabling connections over longer distances within a building. The module is used in a wired system and is inserted into an expansion socket of the COMpact 3000 series.

Functions and Equipment in Detail
The COMpact S0 module provides a single internal S0 port configured as a multi-device connection (PTMP). This allows multiple end devices to be connected to a single port, with a maximum of two COMfortel system telephones. Connection options include both screw terminals and an RJ45 socket, facilitating integration into various installation environments. The S0 (4-wire) connection type is active by default, and according to the source, switching to UP0 (2-wire) is possible for internal use, enabling older analog lines to be used with modern system telephones.

Technology Explained Simply
The internal S0 port operates according to the Euro-ISDN standard (DSS-1), used for digital transmission of voice and data in German telephone systems. PTMP technology (Point-to-Multipoint) allows multiple end devices to be connected to a single port, reducing the number of required connections. The range of approximately 150 meters is sufficient for most office and commercial buildings, enabling telephones to be connected in different rooms or floors. Wiring is done via conventional cables, with screw terminals or an RJ45 socket selected based on installation requirements.

Compatibility and Accessories
The module is specifically designed for the COMpact 3000 series and can be installed into the expansion slots of these systems. It is compatible with the models COMpact 3000 analog, ISDN, and VoIP. Connection is made via an internal S0 port designed for use with COMfortel series system telephones.

Installation and Mounting
Installation is done by inserting the plug-in module into a free expansion socket of the COMpact 3000 system. End device wiring is done via screw terminals or an RJ45 socket, depending on existing infrastructure. The S0 (4-wire) connection type is active by default, with the option to switch to UP0 (2-wire) for internal use. The maximum range is approximately 150 meters, and wiring should be carried out according to ISDN connection standards.

Operational Advantages
The COMpact S0 module offers a flexible expansion option for existing COMpact 3000 systems without requiring additional exchange connections. Supporting up to two COMfortel system telephones via an internal S0 port reduces the number of required connections and enables cost-efficient expansion. The use of screw terminals or RJ45 sockets provides installation flexibility, and the 150-meter range is sufficient for most indoor environments. Compatibility with the various variants of the COMpact 3000 series (analog, ISDN, VoIP) increases the module’s application possibilities in existing systems.