Operating Manual

INOVA DAS Operating Manual

Alarm and Corrective Action

7.1 Alarm Phenomenon and Solution

7.1.1 TX/RX PLL Alarm

Phenomenon

Cause

- Alarm window: green → red

- MHU : When TX PLL within MRFU is abnormal

- ERU : When TX PLL within ERFU is abnormal

Solution and Action

- Solution : Replace MRFU for MHU, replace ERFU for ERU

- Action : For MHU, replace MRFU of frequency band that alarm generated and check if it works

normally, for ERU, same as MHU, replace ERFU of frequency band that alarm generated

and check if it works normally

7.1.2 TX S/D(High) Alarm

Phenomenon

Cause

- Alarm window: green → red

- When TX output level is higher than shutdown alarm set value

Solution and Action

- Solution: Set to appropriate TX ATTen.

- Action: Set TX ATTen. appropriately according to the environment, turn ALC on and prevent

shutdown.

7.1.3 DTU Alarm

Phenomenon

Cause

- Alarm window : green → red

- When DTU board abnormality such as DTU board connection

harness, DTU board clock, DTU board telecommunication

abnormality occurs