Nortel DCT1900 Technical Product Manual page 217

Installation Instructions, Line Termination Unit (LTU) – REX-BRD0007 or ROFNB 157 02/6 and LTU2 - REX-BRD0019A or ROFNB
C 14
HAPTER
Line Termination Unit (LTU) – REX-BRD0007 or ROFNB 157 02/6 and
14.1 General
The LTU supports 8 two wire analog connections to a PBX.
Maintenance
The LTU contains the following field–exchangeable part (see Figure 14-1):
LTU Firmware - REX-SW0012 or RYS 105 661
LTU2 Firmware - REX-LTU2FW 01/1H
Note: LTU2 can only be used with CPU2 board.
14.2 Board Description
Jumpers
Not applicable.
Connectors
The LTU has 4 connectors at the front by which Line Termination Circuits (LTCs) are connected to
the PBX/Centrex.
1. LTC1 – LTC4: connection of PBX line 1 to 4
2. LTU Ground: connection of signalling earth (ELR)
3. LTC5 – LTC8: connection of PBX line 5 to 8
4. Pin a is tip, pin b is ring. Pins a' and b' are not used.
LEDs
LED1
LED2
LED3
LED4
14.3 Installation
1. Insert the LTU gently into the card guide in its specified board position (See Figure 14-1).
2. Gently push the board into the back connector until it locks. Do not use any force.
3. Connect the connectors from cable set NTM/TSRNB 101 31 to the front of the board.
Install-DCT1900/R8/mw
© 2000-2005
LTU2 - REX-BRD0019A or ROFNB 157 25/2
: Normally on. Power On
: Normally off. Watch–dog
: Normally off. Board not polled
: Normally off. Board Error
Technical Product Manual - DCT1900
14-1