AT&T MERLIN LEGEND Communications System PBX System Planning Manual page 146

Features
ARS Worksheet
In this section, you will define a set of ARS tables. This set includes a list of area
codes and exchanges associated with each table, the preferred and alternate
routes (if any) for each subpattern, and the FRL for each route. As you become
more familiar with the calling patterns of your company, and with the intricacies
of ARS, you may want to change these patterns to suit your particular
installation.
Note: It is recommended that all systems operating in PBX mode use ARS,
even if only central office trunks are available. This provides additional flexibility
for future upgrading of facilities and allows predesignated emergency calls to
be put through regardless of restrictions placed on a station.
Fill out the Automatic Route Selection Worksheet (PBX System Form 9a) to
decide how to best route calls. Use PBX System Form 3b, Outside Trunks —
Pools to review the types of trunk pools available.
Planning Form Instructions
1. Record the number of exchanges in the local calling area in the blank at
the top of Form 9a. If you aren't sure how many exchanges there are,
consult your telephone directory.
2. Enter the number of each of the trunk pools (factory setting is 70 or 890 -
899) in the "Trunk Pool Number" column.
Note: If you have renumbered the trunk pools, check the "Renumber To"
column for Form 3b for the trunk pool extension numbers.
Some trunk pools, such as in-state WATS trunk pools, can be used for
both toll and local calls. (Note that with ARS a local call is any call that
doesn't require dialing a 1.) If people will use a particular trunk pool for
both toll and local calls, enter the number of that trunk pool in the
worksheet twice, and note the reason.
For example, McHale and Associates is based in Denver, Colorado (303
area code). McHale has a local trunk pool, an in-state WATS pool, and a
cross-country WATS pool. Because Colorado has two area codes, 303
and 719, the in-state WATS trunk can be used for both toll and local calls.
Therefore, there are two entries for Pool 890 on the ARS Worksheet.
Figure 4-1 shows the completed Automatic Route Selection Worksheet for the
fictitous company McHale and Associates of Denver, Colorado. you may find it
useful to consult the illustration as you fill out the worksheet.
System Features 4-41