Your question about Siemens S30810-Q2153-X SLMQ

The SLMQ (Station Line Module Digital ANSI-U Interface) board offers 16 two-wire digital line interfaces according to ANSI-U specifications.

It provides ISDN basic access for stations with extremely long lines (5.5 - 9 km).

One ANSI-U interface can accommodate either one direct terminal connection, using the appropriate interface plug, or up to 8 S0 terminals. The S0 bus must be connected via a PNTQ terminator. An ANSI-U terminal with an integrated PNTQ can accomodate an additional 7 S0 terminal connections. If the local feed voltage fails, one ANSI-U terminal or one PNTQ plus one S0 terminal per connection can operate on the (remote) emergency feed voltage.

Each ANSI-U interface offers ISDN Basic Access with a transmission capacity of 64 kbit/s on each of the two B-channels (voice and data) and 16 kbit/s on the D-channel (signaling). The two B-channels can be switched through to any available timeslots of the PCM30 highways in the system.

The D-channel only transmits signaling data, exchanged between the ANSI-U interface and the Common Control (CC).