User manual

Chapter 3. Operation

61202156L1-1 TDU 120e User Manual 3-9

DS1 Monitor Jack

This jack connects the unit to a PBX or other terminal

equipment.

Network Status LEDs

The Network status LEDs display the operational condition

of the network interface located on the controller board in the

unit.

Network Status LED Display Indicates that...

OK (green)

the operation is in the normal mode and no

errors have been detected.

Test (yellow)

the network interfaces is operating in a test

mode. This includes a self-test or a test loop-

back. When illuminated, this LED also indi-

cates that normal data flow is not occurring

on the network interface.

Error (red)

an error has occurred, such as BPV, OOF, or

CRC.

Alarm (red)

an alarm condition has been detected. Any

alarm condition will activate the alarm relay

for the external alarm device. When the alarm

condition is no longer valid, the OK LED acti-

vates (turns on). To view an alarm condition,

select the active alarm menu item.

If the alarm conditions have been corrected, the alarm which

caused the activation of the Alarm LED can be viewed under the

NIT

ISTORY

menu.