Nortel DMS-100 Series Maintenance Manual page 29

Line card type B coin (NT6X18AA, AB, BA)
Message waiting line card (NT6X19AA)
Message-waiting converter card (NT6X20AA)
Meridian Business Set (MBS) line card 15KFT MDC Business Set
(NT6X21AA, AB, AC, AD)
Standard line circuit card type A (NT6X17AA, AB, AC, AD). This
card is the plain old telephone service (POTS) card. This card supports
single-party, two-party, and 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 type A card supports
the cutover control circuit.
Note: The position for LC-00 is assigned to a type A line circuit. The
system uses circuit LC-00 to test analog ringing. Circuit LC-00 is not
available for assignment to a subscriber line.
Line card type B coin (NT6X18AA, AB, BA). This card provides all
features of type A and multiparty lines. The type B card supports coded
ringing, private branch exchange (PBX) ground start and hotel/motel. The
type B card supports analog pay telephone sets that require coin control.
If the suffix of the NT6X18 card is -AA or -AB and the line is ground start
(GND=Y in table LNINV), run diagnostics again if initial diagnostics fail.
To perform this action, add the Service order (SERVORD) option NPGD,
Negate Partial Ground Start Diagnostics. This option allows the system to
test the line against a smaller subset of ground start diagnostics. When you
set option NPGD in table LENLINES, the system skips loop detector,
reversal relay, and ground start relay tests.
Message waiting line card (NT6X19AA) provides the features of the
type A line circuit and a message-waiting lamp driver circuit. When the
circuit becomes active, this circuit causes the message waiting lamp on the
associated telephone set to flash at 1Hz. The flashing lamp informs the
subscriber that the system holds a message.
Message-waiting converter card (NT6X20AA) provides –150 V
synchronized pulse for the message-waiting lamp circuit. This card is
synchronized from the 2.56-MHz clock pulse in the OPAC. Install this card
in slot positions 00 and 16 of the odd LSG for the card to function correctly.
Meridian Business Set (MBS) line card 15KFT MDC Business Set
(NT6X21AA, AB, AC, AD) supports MDC-related electronic multiline
telephone sets and operator consoles.
DMS-100 Family OPAC Maintenance Manual XPM12 and up
Maintenance overview 1-13