Avaya CMC1 사용자 설명서

The maximum range of out-of-building analog telephones (500-, 2500-, or 7100-types) 
connected to an analog line circuit pack should be such that the maximum loop resistance does 
not exceed 1300 ohms.

The following voice terminals cannot be installed in an exposed environment:

●

7300-type voice terminals connected to TN762B Hybrid Line circuit packs

●

Analog telephones connected to TN746B Analog Line circuit packs

1. Refer to 

on page 31 for circuit protector ordering 

information (comcodes).

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 TN754C circuit packs. The ITW Linx may be used on all vintages of 
the TN754 circuit packs. 

 lists the 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 Avaya Inc. representative for more 
information.

1. The 3-type protectors should only be used if they are already part of the 

existing protectif on system. A sneak current protector is always required 
when a 3-type primary protector is used.

3B1A (carbon)

4B1C (carbon)

220029 Fuse

3B1E-W (wide gap 
gas tube)

4B1E-W (wide gap gas 
tube)

SCP-1

3C1S (solid state)

4C1S (solid state)