Toshiba Strata Dk14, Dk40i, Dk424 Installation And Maintenance Manual

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
Strata DK I&M 5/9914-25
ISDN Interfaces
Figure 14-18 TBSU Switch Layout
NoteIt is normal for sockets IC7 and IC8 to be empty.
Table 14-10 TBSU Option Switches, Jumpers, and Connectors 
TBSU
CircuitOption 
SwitchTy p eCircuit TypeDescriptionTENT
All SW 1 Push-button N/A N/AResets firmware on all TBSU circuits. Drops calls off 
the TBSU.
1 SW 100 Jumper X X Causes the circuit
1 to operate as TE or NT.
1. Also requires Program *60 to set TE or NT.
1 SW 101 Slide ON ON Switches a 100-ohm resistor in/out of the circuit.1
2 SW 200 Jumper X X Causes the circuit
2 to operate as TE or NT1.
2. SW2 is for factory use only
2 SW 201 Slide ON ON Switches a 100-ohm resistor in/out of the circuit.2
SwitchTy p eCircuitDescriptionShortCut (remove)
W2 JumperTBSU1A uses the internal 
CPU ROM (IC20)TBSU1A uses the external 
ROM (IC6 and 7)Future Use
SW2 Jumper For factory loop back test. Normal operationUsed for factory 
inspection only. Do 
not cut this jumper.
TBSU1A
3795
SW201
SW1SW200
ON
OFF
ON
OFF
Cct2
Cct1
Cct2Cct1
TB1
TB2
FS
LOS
TS
BSY CD9
CD10
CD11
CD12PFT contacts
Monitor
J1
SW101100
SW100
NT  TE
J3SW2
Loop
BackW2
IC7 IC6
CUT
ROM CPU
SHORT
J2 Reset
NT  TE
100 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
14-26Strata DK I&M 5/99
Modular Jack Pin Configurations
BRI Circuit Jack (TE or NT Mode)
The TBSU and RBSU/RBSS BRI circuit jack is a shielded RJ-45 (8-pin modular) with Transmit 
(Tx) and Receive (Rx) pin numbers as shown in Figure 14-19. The Tx and Rx pin numbers change 
when the BRI circuit is configured with TBSU and RBSU/RBSS option switches for TE or NT 
(Tables 14-8 and 14-10). If the R40S is installed on the RBSU, the PS-1 voltage is carried on the 
Tx/Rx wires with polarity. (See Table 14-11).
The position of the TBSU BRI and RBSU/RBSS circuit jacks are shown in Figure 14-18 and 
14-19 respectively.
Monitor Jack
The TBSU and RBSU/RBSS monitor jack is an RJ-12 (6-pin modular). This jack provides an RS-
232 output that enables you to monitor the TBSU and RBSU/RBSS BRI circuit D-channel, layer-2 
and layer-3 data. The monitor jack pin configuration and communication parameters are the same 
as RPTU and RBUU which are shown in Figure 14-8 on Page 14-13. Figures 14-29 and 14-30 on 
Pages 14-34 and 14-35, respectively, show examples of the TBSU or RBSU monitor jack output. 
Figures 14-10 and 14-19 show the location of the TBSU and RBSU monitor jacks respectively. 
Figure 14-19 Location of LEDs and Connectors Table 14-11 RJ-45 Pins in the 8-pin Modular Jack
Pin 
No.TE 
SideNT 
SidePS1/R40S 
Polarity
1 N/C N/C N/C
2 N/C N/C N/C
3TxRx -
4RxTx +
5RxTx +
6TxRx -
7 N/C N/C N/C
8 N/C N/C N/C
876543213048
Front View of RJ-45 Jack Cavity
Note: The RJ-45 pins are numbered as shown above.
RBSU
Reset Switch
(resets RBSU Firmware)
RS-232C Connector
for Call-Data Monitor RJ-45 8-pin (shielded)
Modular Connector
BSY
TS
LOS
FS
BSY
TS
LOS
FS
2795
RBSS
3rd Circuit 2nd Circuit
1st Circuit 4th CircuitBSY
TS
LOS
FS
BSY
TS
LOS
FSCKT2
CKT1CKT4
CKT3
TB3 (FG)
TB1 and TB2 (PFT) 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
Strata DK I&M 5/9914-27
ISDN Interfaces
TBSU and RBSU/RBSS Premise Wiring Guidelines
Power Failure Terminal Screws
TB1 and TB2 are the connecting points that interface a pair of dry contacts that can be used for 
power failure switching purposes (see Figure 14-19 for the locations). When the DK system 
(TBSU and RBSU) has power (from AC source or batteries) there is a short circuit across TB1 and 
TB2. In the event of no power to the DK424, there is an open circuit across TB1 and TB2. The 
specifications for TB1 and TB2 contacts are:
©Maximum switchable voltage: 30VDC
©Maximum switchable current: 80mA
©Short circuit resistance: Approximately 15 ohms
Grounding Terminal Screws
TB3 is a screw terminal that can be used to connect a ground wire to the RBSU PCB (see Figure 
14-19 for the location). This ground enables the RBSU/RBSS to meet Electro Magnetic 
Compatibility (EMC) requirements. As of Release 4.1, RBSU complies with EMC requirements 
without grounding TB3 on the RBSU, so it is not necessary to connect a ground wire to TB3.
BRI Wire Type Recommendations
CAT3 or CAT5 wire is recommended for ISDN BRI customer-premises wiring. While the ISDN 
BRI signal works for some distance over almost any wire that is suitable for analog voice service, 
better wire enables longer runs. CAT5 provides better 100-ohm impedance matching (at little extra 
cost) between the TBSU or RBSU/RBSS circuit and the station Terminal Equipment (TE-1).
Normally the CAT3 or CAT5 wiring does not have to be shielded when used for ISDN BRI 
premises wiring. However, the RJ-45 jacks on the TBSU and RBSU/RBSS BRI circuits are 
shielded and provide a ground shield in the event that shielded modular plugs and cable are used. 
NoteIf using shielded cable and plugs, cable runs should only be grounded at the DK TBSU 
and RBSU/RBSS, RJ-45 jacks. To prevent ground loops, do not ground both ends of 
shielded cable runs.
TBSU and RBSU/RBSS BRI Cable Jacks and Connectors
In the U.S., the standard connector for ISDN equipment is the eight-pin RJ jack. Patch cables have 
eight-pole plugs at both ends. The same pinout applies to both ends of an ISDN cable, which is the 
practice of the data world. This means that a flat untwisted cable with an RJ modular plug at both 
ends will have the locking tab of the plug on one end, “up;” and, on the other end, “down,” as 
shown in Figure 14-20.
NoteThis is the opposite of telephony “silver satin” cables which have locking tabs on both 
ends facing the same direction. Telephony cables cause the pins at either end to crossover 
while data cables provide a straight through pin-to-pin connection between modular jacks. 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
14-28Strata DK I&M 5/99
A cord of up to 10 meters connects the ISDN BRI RJ-45 wall jack to the desktop TE-1 or TA RJ-
45 jack. Bellcore recommends that all TE-1 and TA devices be attached with the same standard 
cord to ensure compatibility.
Figure 14-20 Modular ISDN Data Cable
The standard pinouts for ISDN jacks is the TIA-568A or TIA-568B jack as listed in Table 14-12. 
The variants A and B to the TIA specification are electrically the same, only the wire colors are 
different. However, you should only use one type TIA jack in a customer installation because 
mixing the two may cause certain wire pairs to be swapped which would result in line faults.
Table 14-12TIA-568A (RJ-45) Jack – ISDN Standard Interface Modular Connector Pinout (RBSU-TE mode)
Notes 
lPins are numbered left to right when looking into the jack cavity with the locking tab down.
lTIA-568B swaps pair two with pair three, changing only the color of the wires on the pins. 
Electrical performance is the same.
PinColorNameFunction
1 Green T2 Power 3 (not used on DK TBSU or RBSU/RBSS)
2 Green/White R2 Power 3 (not used on DK TBSU or RBSU/RBSS)
3 Orange/White R3 Transmit to Network (NT-1, S/T jack) 
4 Blue/White R1 Receive from Network (NT-1, S/T jack)
5 Blue T1 Receive from Network (NT-1, S/T jack)
6 Orange T3 Transmit to Network (NT-1, S/T jack)
7 Brown T4 - Power 2 (not used on DK TBSU or RBSU/RBSS)
8 Brown/White R4 + Power 2 (not used on DK TBSU or RBSU/RBSS)
3039
Four-pair Wire 
RJ-45
Eight-pole PlugLocking Tab 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
Strata DK I&M 5/9914-29
ISDN Interfaces
TBSU and RBSU/RBSS EMC Ferrite Core Requirement
To ensure that the TBSU and RBSU/RBSS circuits meet the EMC requirements, it is necessary to 
run all wire connecting TBSU and RBSU/RBSS circuits (TE mode and NT mode) through a 
Ferrite core. Use Toshiba part number, FER-CORE-ISDN, which is shipped with the TBSU and 
RBSU. Figures 14-21 and 14-22 show how to dress the wiring through the Ferrite core.
Connecting TBSU and RBSU to Network Side (TE-Mode)
The TBSU and RBSU only, not the RBSS, circuits can be connected to the network side of a BRI 
line. The TBSU and RBSU circuits must be configured in the TE-mode (refer to option switches in 
Table 14-8 on Page 14-22 and Table 14-10 on Page 14-25 and Program *60).
In the U.S., the BRI line from the ISDN service provider is a two-wire U-type BRI line. This line 
connects to the TBSU or RBSU TE circuit via a customer-provided NT1 as shown in Figure 
14-23. The NT1 is necessary to convert the network BRI, two-wire, U interface to the TBSU or 
RBSU BRI, four-wire, T interface. The NT1 must be UL listed (U.S.) or CSA certified (Canada).
The NT1 is powered by local AC power via an AC adapter supplied with the NT1. The connection 
between the NT1 and the TBSU or RBSU TE circuit is a point-to-point connection, so the NT1 can 
connect to only one TBSU or RBSU BRI TE circuit. 
A 100-ohm Terminating Resistor (TR) is required on each end of the point-to-point connection. 
The TR must be switched into the TBSU or RBSU TE circuit (refer to option switches in Ta b l e  
14-10 on Page 14-25 and Table 14-8 on Page 14-22) and into the NT1 device.
Most NT1 devices have TR option switches; if the NT1 does not have TRs, two 100-ohm TRs 
must be wired into the NT1 modular jack - one 100-ohm resistor across each pair (Tx and Rx). 
Refer to the NT1 manufacturers documentation for the maximum loop length between the NT1 
and the network jack. The maximum loop length between the NT1 and the TBSU or RBSU circuit 
is 1650 feet.
RBUS
3046Ferrite Core
FER-CORE-ISDN
One Turn
CAT 3, 4, or 5 Cable
Tie Wrap
Note:
RBSS
  Locate the Ferrite core
  as close as possible to
  the RBSU/RBSS.
ISDN PRI Jack
Figure 14-21 RBSU/RBSS Ferrite Core 
Installation
TBSU1AFS
LOS
TS
BSY FS
LOS
TS
BSY
Ferrite Core
FER-CORE-ISDN
One Turn
CAT 3, 4, or 5 Cable
Tie Wrap
Note:  Locate the Ferrite core
  as close as possible to
  the TBSU.
3377
Figure 14-22 TBSU Ferrite Core Installation 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
14-30Strata DK I&M 5/99
Figure 14-23 TBSU or RBSU to NT1 Point-to-point Connection
Connecting TBSU and RBSU/RBSS Station Devices (NT-Mode)
S-type TAs and TE-1s can be connected to the station side of TBSU, RBSU, and RBSS circuits. 
TA and TE devices must be powered by local AC power using AC adapter supplied with the TA or 
TE device. The TBSU and RBSU/RBSS circuits must be configured in the NT mode when 
connected to TA and TE devices (refer to option switches in Table 14-8 on Page 14-22 and Ta b l e  
14-10 on Page 14-25 and Program *60).
The TA enables you to connect non-ISDN voice and data devices to ISDN BRI circuits. The TA 
matches the protocol of existing interfaces (R-reference point) to the ISDN S/T protocol (see 
Figure 14-1 on Page 14-2). TA devices include asynchronous circuit-switched adapters that 
convert RS-232 async data (like data from a PC COM port) to B-channel 64 kbps sync.
TAs also enable you to connect standard telephones and non-ISDN fax machines to receive and 
make calls over ISDN circuits. TEs include any user device (telephone, fax, PC video conference 
board) that is designed to plug directly into the ISDN (S/T) interface without the use of a TA.
There are two types of ISDN TA and TE-1 devices: the U-type and the S/T type. Most 
manufacturers of ISDN station devices make both types. In DK424 R4.1 and DK40i, the TBSU 
and RBSU/RBSS station side, BRI-NT circuits only function with S/T type TA and TE-1 devices. 
You cannot connect U-type TE-1 or TA devices to the TBSU or RBSU/RBSS BRI-NT circuits.
Also, connecting an NT1 to the TBSU or RBSU/RBSS BRI-NT circuit to convert from S/T to U 
interface is not supported to enable the use of U-type TE-1 or TA device on the station side of the 
TBSU or RBSU/RBSS. U-type TE-1 and TA device interface is provided in the DK by the TBUU 
and RBUU/RBUS BRI circuit only. TBUU and RBUU/RBUS will be provided in the DK424 and 
DK40i Release 4.2.
The TBSU and RBSU/RBSS BRI-NT circuit supports the National ISDN 2 (NI2) S-Interface 
“passive bus.” It is called a passive bus, because it contains no logical functions. The TBSU and 
RBSU/RBSS BRI-NT interface supports a point-to-multipoint connection on two twisted pairs. 
Up to two TE-1 and/or TA devices can be connected to one TBSU or RBSU/RBSS, BRI-NT 
circuit. Using standardized wiring and modular connectors, as explained in previous paragraphs, 
TBSU or RBSU
TE-Circuit
Switch in
100-ohm TR
using RBSU
option switch.
RJ-45 Pinout
(TBSU or RBSU - BRI jack)
3343
Network
BRI-line
RJ-11 JackNT-1
Switch
in 100-ohm
TR.
T and U are ISDN standard
reference points. Note:
BRI
(four-wire)
TBRI
(two-wire)
U
Demarcation Point 3
6
4
53
6
4
5 RX
RXTX
TXRX/TX 4
5
RJ-45 Pinout
(NT1 - S/T jack)
Local AC
Power 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
Strata DK I&M 5/9914-31
ISDN Interfaces
maintains control of polarity. The pinout from the TBSU and RBSU/RBSS circuit to a S-type TE-
1 or TA device is shown in Figure 14-24 and Ta b l e  1 4 - 11.
Figure 14-24 TBSU and RBSU/RBSS NT Circuit Pinout on Passive Bus
As a parallel bus, the TBSU and RBSU/RBSS BRI-NT passive bus will accept TE-1 and TA 
devices scattered on the bus; however, the locations of the TE and TA devices on the S bus is 
limited by timing considerations. Specifically, the round trip propagation delay of a signal from the 
TBSU or RBSU/RBSS circuit to one device must be within four microseconds of the delay from 
the other device on the bus. That is to say, layer-1 frames from the TBSU and RBSU/RBSS must 
be received within a two microsecond window. This says nothing about how large the delay can 
be. In fact, it can be much larger, as long as the differences remain small.
To control electrical characteristics, a 100-ohm terminating resistor (TR) is required at both ends 
of the passive bus. One resistor should be across the Tx pair and one across the Rx pair at either 
end of the passive bus. Branch-type passive bus configurations, shown in Figures 14-25~14-28, 
may only require a TR on the TBSU or RBSU/RBSS NT circuit side and not on the TE or TA 
device side of the bus.
The TBSU, RBSU, and RBSS circuits provide an option switch that allows the 100-ohm TR to be 
switched into the circuit on the DK side of the bus (see Table 14-8 on Page 14-22 and Table 14-10 
on Page 14-25). Most TE-1 and TA devices also provide option switches to connect 100-ohm 
terminating resistors as shown in Figure 14-23.
If the TE or TA devices do not provide TRs, they may be permanently wired in place on a RJ-45 
jack at the far end of the bus. Only one terminating resistor on each pair should be on the far (TE) 
end of the passive bus - do not switch in TRs on more than one TE-1 or TA device on the passive 
bus.
Important!The correct placement of TRs on the Passive Bus is critical to ISDN BRI circuit 
operation (see the following TBSU and RBSU/RBSS Passive Bus configurations 
section).
TBSU or RBSU
NT Circuit
Insert 100-ohm
TR using RBSU
and RBSS
option switches.
RJ-45
Pinout
3344
S-type, TE-1s  or TAs  without
100-ohm terminating resistors
(maximum eight TE-1s or TAs per
RBSU/RBSS circuit). BRI (four-wire)3
6
4
53
6
4
5
RJ-45
Pinout
S-type, TE-1  or TA  with
100-ohm TR or just a 
100-ohm terminating
resistor across each pair
on a RJ-45 jack.
To local
AC Power
To local
AC Power
3645 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
14-32Strata DK I&M 5/99
TBSU and RBSU/RBSS Passive Bus Configurations
The placement of S-type TE and TA devices on the BRI S-passive bus is critical for good TBSU 
and RBSU/RBSS BRI circuit performance. Figures 14-25~14-28 show four passive bus 
architectures that are known to work. In all installations, follow the guidelines of any of these 
passive-bus models using the wire, cables, and jacks described in the previous paragraphs.
Figure 14-25 Simplified Short-branched Passive Bus
Figure 14-26 Branched Passive Bus
RJ-45
TBSU or 
RBSU/RBSS  
NT-Mode360 max
3338360 max
TA and PC Com Port
ISDN Telephone
TR
RJ-45
3339
*
*
850No more than 130 difference
between any 2 branches. *
TBSU or
RBSU/RBSS  
NT-Mode
TR
RJ-45 with
TRsTE-1 PC Card
ISDN Telephone 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
Strata DK I&M 5/9914-33
ISDN Interfaces
Figure 14-27 Extended Passive Bus
Figure 14-28 Short Passive Bus
3340
TR
165082
RJ-45
TBSU or
RBSU/RBSS  
NT-Mode
TRISDN Telephone TE-1 PC Card
3341
TR
640 490
RJ-45
TBSU or
RBSU/RBSS  
NT-Mode
TRISDN Telephone TE-1 PC Card 
						

							ISDN Interfaces
RBSU/RBSS and TBSU Interface Units
14-34Strata DK I&M 5/99
TBSU and RBSU/RBSS BRI Call Monitor
The call-monitor jack located on the TBSU and RBSU enables you to use a PC or ASCII terminal 
to monitor the BRI, D-channel call setup, layer-2 and layer-3 data (refer to Figure 14-8 on Page 
14-13 for information about connecting the monitor jack). Figures 14-29 and 14-30 provide 
examples of BRI call setup message information that is available from the TBSU and RBSU call-
monitor jack.
Figure 14-29 Outgoing Call Setup Output of BRI Call Monitor