Instruction manual

MERLIN LEGEND Communications System Release 5.0
System Planning
555-650-112
Issue 1
June 1997
Lines/Trunks
Page 3-44Selecting Line/Trunk Options
3
Planning Form Instructions
On Form 3i, Incoming Trunks: BRI Options (800 NI-BRI Module), under the
“Timers and Counters” heading on page 2:
1. For each timer:
■ To keep the factory setting, check the first box under the timer
name.
■ To change the factory setting, check the second box under the timer
name and write the new threshold in the space provided.
Table 3-5. NI-1 BRI Timers
Compensating for Slow Dial Tone (International)3
If this system is being installed outside of the US , problems can arise because of
slow dial tone from local telephone companies due to the limitations of their
switching equipment. If this is the case, be aware of the following:
■ Users should be instructed to wait for dial tone before they dial. (Due to
changes made to internal timers, the system will allow the delay.)
■ The following features cannot be used:
— Automatic Route Selection
— Remote Call Forwarding
— Remote Access (outgoing)
Name Description
Factory
Setting
Allowable
Threshold
T200 The minimum time which Layer 2 must wait
for an acknowledgment of a link
establishment frame, an information frame,
or a polling supervisory frame, before
initiating retransmission procedures.
1,000 ms 500−5,000 ms in
increments of 500 ms
T203 The maximum time for which the Layer 2
link can remain inactive.
33 seconds 10–255 seconds in
increments of 1 second
T303 The delay in CO response after the system
has sent a SETUP message to initiate an
outgoing call.
4 seconds 2–10 seconds in
increments of 1 second
T305 The delay in response from the CO after the
system has initiated a DISConnect message
for call clearing.
30 seconds 2−60 seconds in
increments of 1 second
T308 The delay in response from the CO after the
system has sent a RELease message for
call clearing.
4 seconds 2−10 seconds in
increments of 1 second