572 / TestsModular ICS 7.1 Installer Guide N0130943 02Operating a Continuity loopback testInstaller password requiredYou start the Continuity loopback test by pressing the buttonon the front of the DTI. Calls on all lines on the cartridge areautomatically dropped when a loopback test is invoked.• The red LED above the button remains on until the test iscanceled.• Invoking a continuity loopback test automatically cancelsany other test in progress.• To stop the continuity loopback test, press the button onthe DTI. The red LED above the button turns off when thetest is canceled.Loopback test for BRI lines Installer password requiredThe loopback test for BRI lines loops the incoming BRIpayload back to the local exchange (service provider) forevaluation of the transmission quality. Loopback tests shouldbe conducted only under the guidance of the service provider,and the results from these tests are returned to the serviceprovider.You can run loopback payload tests simultaneously onmultiple loops or multiple cards. The loop must be provisionedto perform the test. All calls on the card you are testing will bedropped at the start of a loop payload test.Give notice that you are running a loopbacktest.Calls on all T1 or PRI lines on the DTI will beautomatically dropped when a loopback test isinvoked. Use the Page feature to notify peopleusing the system that a test is about to begin andthat calls will be disconnected.
