Capacity And Cabinet Slot Information; Ps-1 Backup Power Option - Toshiba Strata DK40 Installation & Maintenance Manual

RBSU/RBSS ISDN Basic Rate Interface Unit
the same BRI circuit. The contention rule for the two BRI B-channels is first come, first
served.
RBSU ST ref points
TE
8
or
TA
1
TE
or
TA
Figure 3-24

Capacity and Cabinet Slot Information

The RBSU/RBSS can be installed in any slot in the Expansion KSU Cabinet (Slots 15 ~ 18).
Each RBSU and/or RBSS contains two circuits and each circuit reduces the system capacity
by two station ports or two exchange lines (one port/line per B-channel). Therefore, if the
RBSU PCB is installed, and configured for TE mode, the exchange line count will increment
by four lines. If the RBSU is configured for NT mode, the station count will increase by four
stations.
The RBSU PCB can only be configured for NT mode.
A maximum of two RBSU and RBSS PCBs can be installed in the DK40 system. The total
number of RBSU/RBSS circuits allowed in the DK40 is shown in
Table 3-13 RBSU/RBSS, BRI-TE, and BRI-NT Maximums
Processor
PCBs combined
DK40
* RBSU circuits can be NT or TE, but RBSS circuits can only be NT.

PS-1 Backup Power Option

The RBSU provides an optional backup power supply, R40S, that will supply backup power
to TE devices in the event of an AC power loss. The R40S is also used in the instances where
some connected devices may require extra power. This power backup option only applies to
RBSU or RBSS circuits that are configured in the NT mode. Refer to
to install the R40S onto the RBSU.
Also the DK40 system must have battery backup to allow the R40S power backup function to
operate. The R40S power supply is an ISDN, PS-1 type power unit which means it supplies
Strata DK40 I&M Manual Spring 1999
Refer to the Strata DK40 Programming Manual or DK Library CD-Rom for more details.
BRI-NT
(4-wire)
RX
DK40
RBSU/RBSS
TX
S
S, T, and U are ISDN reference points.
TE = S-type Terminal Equipment
TA = S-type Terminal Adaptor
RBSU/RBSS Interfaces between the S/T Reference Points
Maximum
RBSU/RBSS*
4
BRI-TE
(4-wire)
RX
TX
T
Maximum Maximum
BRI-TE BRI-TE
Circuits Channels
4 8
DK40 Universal Slot PCBs
BRI
(2-wire)
NT1
RX/TX
U
Table 3-13.
Maximum
BRI-NT
Circuits
8
Figure 3-28
ISDN
Maximum
BRI-NT
Channels
16
to see how
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