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2 Hardware Installation
2. Connecting the ISDN-Controller T1 to the NTPMKU
or NTPMGF (NTs with T-shaped mounting plate)
Examine your NT and determine which type it is. In case
of doubt, contact your ISDN operator’s technical ser-
vice.
When errors and malfunctions occur at the NT, the S
2M
interface may no longer synchronize with the local
switch. In this case the switch temporarily disables
the PRI. This is indicated by a red LED on the NT.
Newer local switches re-enable the interface again
automatically.
Such synchronization errors may occur during the
AVM ISDN-Controller T1/T1-B connection proce-
dure. If the line is not automatically re-enabled,
contact your ISDN operator’s technical service.
2.3.1 Connection to the NTPM (NT with Terminal
Board)
To ensure that the S
2M
interface remains synchro-
nized with the local switch when no terminal equip-
ment is connected, the is NT usually outfitted with wire
jumpers between terminals S2M ab/a and S2M ab/b,
and between terminals S2M an/a and S2M an/b (“an”
= in; “ab” = out). These jumpers must not be removed
until the terminal equipment—in this case, the AVM
ISDN-Controller T1/T1-B—is operational, i.e. its
driver software has been loaded.
1.
Connect the 9-pin sub-D connector of the cable to
the 9-pin socket of the AVM ISDN-Controller
T1/T1-B (see Fig. 3 in Appendix B, Illustrations).
Secure the connection by tightening the finger
screws. Route the 6 meter cable as directly as
possible to the NT.
2.
Unlock and remove the cover of the NTPM’s
connection terminals.