System Technology; Power Requirements; Diagnostic Maintenance; Programming The Phone System - Panasonic DBS 576HD Technical Manual

System Technology

The DBS 576HD is a completely digital system. Information is
exchanged between the major system components using Pulse
Code Modulation (PCM). The conversation exchange between digital
telephones is also digital, converting the digital information to analog
just before it reaches your handset or speaker.
Stored Program Control (SPC) is accomplished via 16-bit and 32-bit
processors. This technology controls the powerful system features of
the DBS 576HD. Each processor's customized memory (program
settings) is backed up by an on-board, 7-year lithium battery.
The system provides maximum protection from outside power
surges, with built-in triple surge protection for CO outside line
connectors.

Power Requirements

The system must be connected to an input power source of 117V AC (+/-10%), 60 Hz. Each cabinet's
power supply automatically generates 5V DC and 24V DC necessary to power the various printed
circuit boards for station and peripheral equipment. Optional backup batteries are available, and are
designed to safely fit into the cabinet. The power supply contains a charger that maintains a full
charge to the backup batteries, which have a 3-year life and can support the phone system for up to
30 minutes at a time.

Diagnostic Maintenance

The printed circuit board (PCB) cards are designed to slide easily into slots within the DBS 576HD
cabinet. By using diagnostic troubleshooting, small problems can be isolated to specific cards. Some
cards are designed to be installed and extracted from slots without turning off the power, allowing
system maintenance to be completed without interrupting the entire system.
For example, say you're having a problem with one of the trunks on a Loop Start/Ground Start Trunk
Card. Instead of having to turn off the power, or reprogram anything, or alert anyone to get off the
phone, all you have to do is throw a Maintenance switch on the Card. This will busy-out the trunks on
that Card that aren't being used at the moment, but will leave the trunks in use alone, allowing people
to finish their phone calls without any disruption. The LEDs on the Card will tell you when the trunks
become vacant. When all LEDs are extinguished, the Card can be replaced.

Programming the Phone System

Programming can be accomplished in several ways without disrupting normal phone system
operation. Most programming changes take place as you are programming, what we refer to as "live"
programming.
Programming from a display telephone.
Programming can be performed on any small-display or large-display extension phone. A large-
display phone is recommended because its LCD buttons can perform special one-touch functions in
programming (such as "stepping" through addresses, entering a pause in a speed-dial number, etc.).
Only authorized access is allowed; you must enter a valid password to get into Programming mode.
Chapter 1 - System Overview 15