Lucent Technologies definity Installation Manual page 96

DEFINITY Enterprise Communications Server Release 6
Installation and Test for Compact Modular Cabinets 555-230-128
1 Install and Cable the Cabinets
Install Off-Premises Station Wiring
Digital Out-of-Building Telephones
Protection is required at both building entrances for digital out-of-building voice
terminals. There are 2 different types of protectors that can be used to protect
digital voice terminals and digital line circuit packs. The 2 protectors to use are
the 4C3S-75 Enhanced protector and the ITW Linx Enhanced Protector. These
units provide primary and sneak current protection. The 4C3S-75 is equipped
with a heat coil for sneak current protection. The ITW Linx is equipped with
replaceable fuses for sneak current protection.
The 4C3S-75 is only used with Vintage 14 or newer TN754 circuit packs. The
4C3S-75 can be used on all vintages of the TN754B circuit packs. The ITW Linx
may be used on all vintages of the TN754 circuit packs.
approved protectors.
NOTE:
The TN2181 (2-Wire 16 Port Digital Line circuit pack) may not be approved
for some out-of-building uses. Contact your Lucent Technologies
representative for more information.
Table 1-15. Digital Voice Circuit Protectors
Circuit Pack
TN754 V13 or earlier
TN754 V14 or later
TN754B all vintages
TN2181
TN2224
When possible, all new and reused wiring installations should use blocks that
accept the standard 5-pin plug-in 4C3S-75 protector. However, this may not be
cost-effective in some cases. For these installations, the ITW Linx protector may
be installed. An example of this is where screw-type carbon block protectors (or
other non plug-compatible types) are in place and it is too costly to re-terminate
the outside plant cable on a 5-pin mounting block for only a few out-of-building
terminals.
The ITW Linx Enhanced Protector may be installed in series with existing primary
protection. Note the 4C3S-75 protector cannot be installed in series with other
types of primary protection. It must be installed as the only protection on the line
entering the building. For the 4C3S-75 protector, various 25-, 50-, and 100-pair
protector panels are equipped with 110-type connecting blocks and/or RJ21X
connectors. The ITW Linx Enhanced Protector mounts directly on connecting
blocks and requires a separate ground bar.
Enhanced Primary Protector
(With Sneak Current Protection)
ITW Linx Only
4C3S-75 or ITW Linx
4C3S-75 or ITW Linx
4C3S-75 or ITW Linx
4C3S-75 or ITW Linx
Issue 3
May 1998
Page 1-88
Table 1-15 lists the