Capacity And Cabinet Slot Information; Ps-1 Backup Power Option - Toshiba STRATA CTX100 Installation And Maintenance Manual

ISDN Interfaces
RBSU/RBSS Interface Units
connection. The terminal-side (S-point) of the RBSU/RBSS BRI circuit can have parallel
connections of up to two TE-1s or TAs maximum.
When multiple TE-1 and TA devices are installed on a single RBSU/RBSS BRI circuit, the devices
must share, or contend for, that circuit's two B-channels. That is to say, a maximum of two
simultaneous voice and/or data calls are allowed between both devices connected to the same BRI
circuit. The contention rule for the two BRI B-channels is first come, first serve.
Figure 5-7 RBSU/RBSS Interfaces between the S/T Reference Points

Capacity and Cabinet Slot Information

The RBSU/RBSS can be installed in any slot except in a slot that has been left vacant to provide
capacity for RDTU, RPTU2 or RPTU as shown in
contains two circuits and each circuit reduces the system capacity by two station ports and two CO
lines (one port/line per B-channel). Therefore, if the RBSU PCB is installed, the station port and
CO line count will increment by four ports and four lines at the RBSU cabinet slot.
If the RBSU/RBSS is installed, the station port and CO line count will increment by eight station
ports and eight lines at the RBSU/RBSS cabinet slot. RBSU and RBSS PCBs can be installed in
any combination so long as the number of RBSU PCBs is the same or greater than the number of
RBSS PCBs. See
page 1-25

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. This power backup option only applies to RBSU or
RBSS circuits that are configured in the NT mode. See
Also the Strata CTX 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 power
to TE devices on the RBSU/RBSS transmit and receive wire pairs as shown in
power arrangement is also known as phantom power.
Each of the four circuits on RBSU/RBSS can be connected to share the R40S using option
switches on the PCBs (see
the TE devices do not require more power than the R40S can supply and the TE is compatible with
the ISDN PS-1 power arrangement.
5-12
3336 BRI-NT
(4-wire)
TE-1
RX
2
or
TA
TX
TE-1
or
TA
S
S, T, and U are ISDN reference points.
TE = S-type Terminal Equipment
TA = S-type Terminal Adaptor
"ISDN BRI Digital Station PCBs" on page 1-39
for the maximum BRI circuits allowed.
Table 5-4). Before using the R40S as a backup power source, make sure
BRI-TE
(4-wire)
RX
DK TBSU or
NT1
RBSU/RBSS
TX
T
Tables 1-54
Figure 5-11
BRI
(2-wire)
PSTN
RX/TX
U
and 1-55. Each RBSU and/or RBSS
and "Worksheet 3: CO Line" on
to install the R40S.
Figure 5-8. This
Strata CTX I&M 10/02