Cabling - Toshiba STRATA CTX100 Installation And Maintenance Manual

Cabling

To meet Part 15 of FCC Rules, ISDN PRI equipment must be connected using CAT5, Shielded
Twisted-Pair (STP) cabling between the CSU and the RPTU. CAT5 STP protects against cross
talk, Radio Frequency Interference (RFI), and/or Electro Magnetic Interference (EMI). STP
protects ISDN signal data while being transmitted through the cable and keeps the cable itself from
emitting EMI and RFI.
Important! To avoid ground loops, connect only the RPTU end of the shielded cable to ground.
The Strata CTX grounds the CAT5 cable shield between the Strata CTX and CSU at
the RPTU RJ45 jack. You do not have to connect the CSU ground drain. The CSU
ground should not be connected to the cable shield.
Shield continuity must be maintained from the RPTU to the CSU, particularly if using extension
connecting cables. Keep the cable as short as possible between the CSU and the PRI Demarcation
jack, because there is no shield between the CSU and the Demarcation jack.
Toshiba provides a cable kit (Part No. RPRI-CBL-KIT), that contains all that you need to connect
the network ISDN jack to the network side of most CSUs and the equipment side of the CSU to the
RPTU PCB. Depending on the manufacturer, the CSU may use DB15 or modular jacks. If the CSU
is equipped with the modular jacks, the DB15/modular adapters are not used. If this is the case,
make sure the CSU modular jacks are not shielded jacks. Refer to
A detailed pinout diagram for the RJ45 jacks (USOC RJ48C or RJ48X) and the modular cords/
adaptors is shown in
Cable Length
The distance between the RPTU and CSU or RPTU and other Customer Premise Equipment (CPE)
may vary (0~655 ft.). The RPTU must be equalized and its impedance must match the impedance
of the connecting cable. Set SW1 on the RPTU for the proper cable length as shown in
Refer to Figure 5-1
Table 5-3 SW1 Settings
SW1
1
2
3
4
5
6
7
8
Notes
The modular pins are numbered left to right when looking into the jack cavity with the locking
•
clip down.
Shield continuity must be maintained between the RPTU and the CSU, particularly on
•
extension cords. Since there is no shield continuity across the CSU and network jack, the cable
should be kept as short as possible.
Strata CTX I&M 10/02
Figure 5-4 on page 5-8.
for switch locations.
Short
(0 - 150 ft.) (150 - 450 ft.)
On
Off
Off
Off
Off
Off
Off
Not Used Not Used
Figure 5-3
Medium Long
(450 - 655 ft.)
Off
On
Off On
On
Off On
On
Off On
Not Used
ISDN Interfaces
RPTU Installation
for more information.
Table 5-3.
Off
Off
Off
Off
5-7