8434 and 8434DX Voice Terminal
Wiring Information
The 8434 and 8434DX voice terminals work in both 4-wire and 2-wire DCP configurations. The
table below describes the pins on an 8400-Series voice terminal LINE jack.
LINE INTERFACE
PIN PAIR NAME DESCRIPTION
1 2 OD1 4-Wire Output
2 2 OD2 4-Wire Output
3 3 ID1 4-Wire Input
4 1 U-T 2-Wire (Tip)
5 1 U-R 2-Wire (Ring)
6 3 ID2 4-Wire Input
7 4 P1- Adjunct Power -48V
8 4 P2+ Adjunct Power Common
Notes: Regardless of which configuration is in use, ALL wiring between the PBX and the
terminal MUST consist of twisted-pairs, including the modular line cord. The line
cord must be a D8W, which consists of 4 twisted-pairs, or an AT&T approved
equivalent.
Twisted-pair wiring is used to make lines less sensitive to crosstalk. Therefore,
failure to use twisted pair wiring may result in less-than-optimum performance of
the terminal and may also contribute to problems with the line.
An 8-wire modular cord MUST be used for all 4-wire and any 2-wire installations
requiring auxiliary power.
3-286