Installation manual

74 20/10/2004 PS10270JENAA01
Wiring analogue trunk lines
The LR4 card allows the connection of four analogue trunk lines (TKs). This card handles
signalling and the disconnection monitoring function. The release signal (polarity inversion) must
be sent by the public exchange; the signal is detected by the LR4 card.
If the PSTN does not send this signal, the LR4 card must be fitted with a DTOC 'line busy'
detection daughter card for each TK.
Note: The basic LR4 card (with no DTOC) has the reference HJ2765BA and with a DTOC,
HJ2765FA.
Connecting a trunk
Public
networ
k
CO line 1
CO line 2
CO line 3
CO line 4
Safety modules
(PSTN line surges)
LR4 card