Avaya CMC1 manual Digital Out-of-Building Telephones

Installing and Cabling the Cabinets

Table 23: Analog Line Circuit Protectors

Protectors

Primary1	Primary	Sneak Current
	(with heat coil)	Protectors1
3B1A (carbon)	4B1C (carbon)	220029 Fuse
3B1E-W (wide gap	4B1E-W (wide gap gas	SCP-1
gas tube)	tube)
3C1S (solid state)	4C1S (solid state)

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.

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 Table 4: Comcodes for CMC1 on page 31 for circuit protector ordering information (comcodes).

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 TN754C circuit packs. The ITW Linx may be used on all vintages of the TN754 circuit packs. Table 24 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.

136 Installation, Upgrades and Additions for Avaya CMC1 Media Gateways