Nortel Networks 1000 - Manual (Page 463)

Functional description 463
— card identification (card type, vintage, and serial number)
— firmware version
— self-test status
— programmed configuration status
•
receipt and implementation of card configuration:
— programming of the CODECs
— enabling/disabling of individual units or entire card
— programming of input/output interface control circuits for
administration of line interface unit operation
— enabling/disabling of an interrupted dial tone to indicate call waiting
— maintenance diagnostics
— transmission loss levels
Signaling and control
The signaling and control portion of the card provides circuits that
establish, supervise, and take down call connections. These circuits work
with the system CP to operate the line interface circuits during calls. The
circuits receive outgoing call signaling messages from the CP and return
incoming call status information over the DS-30X network loop.
Circuit power
The +8.5 V dc input is regulated down to +5 V dc for use by the digital
logic circuits. All other power to the card is used by the line interface
circuits. The +15.0 V dc input is regulated down to +12 V dc to power the
analog circuits. The –48.0 V dc input is for the telephone battery.
Ringing power for telephones is 86 Vrms ac at 20 Hz on –48 V dc. The
Rsync signal is used to switch 20 Hz ringing on and off at the zero current
cross-over point to lengthen the life of the switching circuits.
Power for lighting the message waiting lights is provided by either the
peripheral equipment power supply or the ringing generator. Logic on the
message waiting line card interrupts the –150 V dc signal at 1 Hz intervals
to provide a flashing message waiting light.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 02.06 Standard
27 August 2008
Copyright © 2003-2008 Nortel Networks
.