Nortel DMS-100 Series Maintenance Manual page 45

A complete LEN for a Star Hub line card includes five units of information, as
described in the following table. The example shows LENs for line cards in a
typical office. The first two LENs are for Star Hub-supported lines.
Line cards are available in several types so the Star Hub can support different
types of analog or digital telephone equipment. The following line cards are
supported:
• Standard line card type A (NT6X17AA, AB, AC, BA) or plain old
telephone service (POTS) card. The type A card supports single-party,
two-party, and private branch exchange (PBX) analog telephone sets (type
500 or 2500). The type A card supports loop start, superimposed ringing,
and frequency selective ringing with bridged ringers. The cutover control
circuit is also supported. See line card type B, coin.
Note: The position for LSG 0 Ckt-00 is assigned to a type A line circuit
and used for analog ringing tests. Circuit LSG 0 Ckt-00 is not available
for assignment to a subscriber line.
• Line card type B, coin (NT6X18AA, AB, BA). The type B card provides
all features of type A, plus multiparty lines. It supports coded ringing,
PBX, ground start, hotel/motel, and analog pay telephone sets that require
coin control.
Note: If the suffix of the NT6X18 card is AA or AB, and the line is
identified as ground start (field GND=Y in table LNINV), run the
diagnostics again if the initial diagnostics fail. This action is possible by
adding the service order (SERVORD) option NPGD (Negate Partial
Ground Start Diagnostics). Option NPGD allows the line to be tested
against a smaller subset of ground start diagnostics. Therefore, when
option NPGD is set in table LENLINES, the loop detector, reversal
relay, and ground start relay tests are not performed.
• Message-waiting line circuit (NT6X19AA). The message waiting line card
provides all the features of the type A line circuit, plus a message-waiting
lamp driver circuit. When activated, this circuit causes the message
waiting lamp on the related telephone set to flash at 1 Hz, telling the
subscriber that a message is being held.
Note 1: When an NT6X19AA message waiting line card is installed, an
NT6X20AA message waiting converter card is required.
Note 2: When an NT6X19AA message waiting line card is installed,
only a metering line card without +48 V can be used.
• Message-waiting converter (NT6X20AA). The message waiting converter
provides -150V synchronized pulse for the message-waiting lamp circuit.
Synchronization is from the 2.56-MHz clock pulse in the Star Hub. This
DMS-100 Family NA100 Star Remote System XPM15 and up
Star Remote System hardware 2-25