Normal And Immediate Ringing - Nortel DMS-100 Series General Description Manual

1-2 DMS-100 ringing overview
Figure 1-1 Illustration of a DMS-100 ringing cycle
Note: The time slot duration for LCE ringing varies with the ringing
scheme. If ringing is superimposed or coded, all time slot durations are 500
ms. If frequency selective ringing (FSR) is used, time slot 0 is 60 ms, time
slot 1 is 65 ms, time slot 2 is 75 ms, and the remainder of the time slots are
45 ms each. The total duration for the ringing cycle remains 6 s.
Operating company personnel can define the time slot and subcycle durations
according to the type of ringing scheme being used.

Normal and immediate ringing

The DMS-100 switch applies power ringing to a line in either normal or
immediate ringing mode. In the normal ringing mode, the DMS-100 switch
297-1001-131 Standard 06.01 October 2000
Time slot
(500 milliseconds[ms])
0 3
1 2
Time slot
(500 ms)
0 3
1 2
Subcycle
0
Time slot
(500 ms)
0 3
1 2
Phase 1
LME ringing cycle
Ringing cycle
(6 s)
4 5 6 7
LCE ringing cycle
Ringing cycle
(6 s)
4 5 6 7
Subcycle
1
SCM ringing cycle
Ringing cycle
(6 s)
4 5 6 7
Phase 2
8 9 10 11
8 9 10 11
Subcycle Subcycle
2 3
8 9 10 11
Phase 3