1.2
Understanding DID Operation
The DID line is a reverse battery, loop start, two-wire voice circuit. (The term reverse battery means that it is the
DXP Plus and not the CO that provides tip and ring supervisory battery for the loop.) The PBX supervision
battery, tone address, supervisory tones, and voice signals are transmitted across the voice pair.
The line
interface at the DXP Plus provides loop current detection, loop pulse digit collection, DTMF receivers, and a
polarity reversal circuit.
In the idle state, the loop is open at the CO end, with on-hook battery polarity maintained on the circuit by the
DXP Plus. The CO requests service from the DXP Plus by applying a resistive termination across the line tip and
ring leads. The DXP Plus recognizes current flow in the loop as a CO connection and prepares for the incoming
call. The CO does not send ringing since the DXP Plus generates it internally and sends it to the stations.
After the DXP Plus receives all of the address digits, it will translate the digits based on the appropriate DID
block translation table and attempt to place the call to the desired station. To assure that the caller will always hear
ring back prior to the call being answered (for example, when answered by voice mail), the system delays the
station ringing until it applies ring back tone.
During station ringing, the called station will sound a distinctive ringing based on the ring code in the translation
table. If the translation table has a name for this CO digit string, the LCD of the called stations will display that
name. Otherwise, the DID block name will display followed by a portion of the CO digit string. If there is
neither CO digit string name nor DID block name programmed, the station LCD will display just the CO digit
string.
If an incoming call is addressed to either an unassigned or an uninstalled station, the DXP Plus will route the call
to the DID block alternate extension. If the DID Block alternate extension is unavailable, it routes the call to the
Dial 0 attendant. If the Dial 0 attendant is either unprogrammed or uninstalled, the DXP Plus will return reorder
tone to the caller.
IMI89–191
Installing The DID Line Board
2 – Installing The DID Line Board
Содержание DXP Plus Series
Страница 1: ...Digital Communications System R ...
Страница 363: ...Automatic Call Distributor Technical Manual R QuickQ DXP ...
Страница 424: ...Automatic Call Distributor System Manager s Guide R QuickQ DXP ...
Страница 500: ...Wrap up Time 1 6 Wrapping Up A Call 4 3 Z Zoom Box A 2 GCA70 271 Index I 3 ...
Страница 628: ...Interconnecting The VMI X Installing And Programming For ExecuMail IMI89 206 Installing And Programming For ExecuMail 5 ...
Страница 677: ...Connecting The Equipment Installing And Programming The OPX X IMI89 209 Installing The OPX X 7 ...
Страница 728: ...DP I I I I and FX Series Digital Communications Systems Understanding The Visual Man Machine Interface COMDlA ...
Страница 1112: ...9 08 8 90 1 13 4 78 3 94 UNIS029 TAB003 PLS page 6 GCA40 130 DXP Plus General Description 11B Telephone Features ...