Ringing Generator Capacity - Nortel DMS-100 Series General Description Manual

2-8 Ringing in Series I peripherals
If operating company personnel repair the RGI fault and return the unit to
service, the DMS-100 CC, upon seeing that the RGI is now in-service, issues
a take back command to the LM or RLM controller. In response, the LM or
RLM controller disconnects the bay 0 RGI link to the bay 1 ringing generator
over the crossover link and reconnects it to the other ringing generator in its
own bay. It then reconnects the RGI links in bay 1 to the ringing generators in
bay 1. This resumes the normal configuration as illustrated in Figure 2-3,
"Normal ringing configuration in LM/RLM" on page 2-5.
Some calls in the ringing state during take back are switched to the other
ringing generator. Because the LM or RLM ringing generators are not
synchronized, this can result in noticeable discontinuity in the ringing cadence
for ringing lines switched to the other ringing generator. The following figure
illustrates a possible result of switching ringing generators on a ringing line.
Figure 2-5 Switching ringing generators - possible effect on ringing lines

Ringing generator capacity

The LM and RLM software limits the number of lines the ringing generator
can ring simultaneously to 15 lines. When a ringing request is received, the
LM and RLM software examines the next 12 time slots and determines the
appropriate time slots of the ringing cycle for the schedule ringing request. It
then checks the number of lines the ringing generator is currently servicing
during those time slots to determine if the new request can be added without
exceeding the 15-line limit.
If the limit is reached, the LM and RLM software will queue the ringing
request for up to two seconds. If the request can not be scheduled within the
two-second queueing period, the call is blocked and the called party is routed
to the treatment facility and receives the fast busy (T120) tone. An associated
log report is output at the DMS-100.
297-1001-131 Standard 06.01 October 2000
RG 0
RG 1
Resulting
ring
Switch from RG 0 to
RG 1 at this point