Mike's PBX Cookbook

Suspected Trunk Trouble

Trouble on Analog Trunks

A quick check to diagnose trouble on analog DID trunks is to check the ‘Last Date of Incoming Call’, or LDIC. Go into Load 36 (LD36) and type LDIC (space) customer # (space) Route # <return>. The printout should indicate zeros for all of the trunks in route. This indicates that trunks processed at least one incoming call since midnight of that day.

If there is a number other than zero, then the trunk has not processed any incoming calls for the number of days indicated, and requires further testing. (In our last newsletter there is a Tech Tip providing an easy way to test the trunk circuit in the switch.)

Analog Combination Central Office Trunks can be quickly tested from the console. Press a ‘bop’ key, then press the ‘Barge In’ key, dial the trunk access code, the trunk member number and then the ‘#’ key.

If the trunk is working, you will hear a dial tone from the telephone company central office. Press the RLS key and repeat this process until all of the trunks are tested. It is best to perform the test early in the day when the console is not busy processing incoming calls.

Trouble on Digital Trunks

To be ahead of trouble on your Digital Trunk it is important to have LD60 included as part of the midnight routine. This will result in a printout that will let you know if the digital T-1 (E-1) spans have experienced problems over the last 24 hours. If the T-1’s are operating properly, all of the midnight printouts should show zeros. In addition, you should check the status of the T-1’s and the individual channels. Go into LD60 and type STAT <return>. The printout will list all of the T-1’s, the alarm status and the status of the individual channels. The normal status of the individual channels should be IDLE or BUSY. Individual channels that are disabled (DSBL) or locked out (LCKO) are not in service and should be enabled and tested.

It is advisable to periodically scan the printout of the maintenance terminal throughout the day. Under normal conditions the message DTC 001 (Clock Controller Tracking or Primary Source Loop) will periodically print out. A message that starts "DTA" is an indication of an alarm status on one or more T-1’s.

NT8D09BA - A New Analog Line Card

The NT8D09BA is a new analog line card that supports 56K and V.90 throughput. This allows you to dial through the switch and get a 56K analog modem connection. Previous analog cards would only allow 28.8 connection speeds. If you have data intensive employees this might be the card for you.

Home » Meridian » Maint » O11 Trunk