ALM-2218 AIS Alarm

Description

If the transmission device detects the failure in transmission, it sends all-1 signals to the next level and triggers the AIS alarm.

Attribute

Alarm ID	Alarm Severity	Alarm Type
2218	Major	Fault

Parameters

ID	Name	Meaning
1	Site No.	Number of the site where the faulty board or module is located Value range: 0-2047
2	Board Type	Number of the type which the faulty board belongs to. 129:TMU
3	Board No.	Number of the fault board 0:TMU 0 1:TMU 1
4	PassNo	Number of the passage where the faulty board is located.
5	SubLink No.	Alarm sub-category number 0～23:The transmission between 0-23 of the E1 port and the upper-level BSC or BTS is abnormal.
6	Cell Index	Index of the cell where the board or module is located 0-2047: Cell index of the faulty cell in the data configuration 65535: None
7	Site Type	Type of the site where the faulty board or module is located 3: BTS30 5: BTS312 10: BTS3012A 11: BTS3006A
8	RackNo	Number of the rack where the faulty board is located.
9	BoxNo	Number of the subrack where the faulty board is located.
10	SlotNo	Number of the slot where the faulty board is located.
11	Site Name	Site Name
12	Alarm Attribute	Alarm Character 0:Normal 1:Transient Count

Impact on the System

The services at the E1 port are interrupted. If it is E1 line 0, communication with the BSC is interrupted.

System Actions

None.

Possible Causes

The transmission link is not available.
The DIP switch settings of the BTS are not correct.
The TMU is faulty.

Procedure

Check the transmission channel.
1. Judge if the faulty E1 line is connected to the other transmission device.
  Y=> Go to Step 2.
  
  N=> Go to Step 3.
2. Check if there is communication faults in the upper level transmission device.
  If there is communication faults in the upper level transmission device, clear the faults. The AIS alarm is cleared.
3. .
Check the DIP switch settings of the BTS.
Check whether the DIP switches S1, S2, S10 and S11 on the TMU panel are correctly set. If no, modify the settings based on the following descriptions:

S1: ON indicates that the impedance over E1 ports 3 and 4 is 75 Ω; OFF indicates the impedance over the two ports is 120 Ω

S2: ON indicates that the impedance over E1 ports 1 and 2 is 75 Ω; OFF indicates the impedance over the two ports is 120 Ω.

S10: ON indicates that the outer conductor of E1 links 1 and 2 is grounded while OFF indicates that the outer conductor is not.

S11: ON indicates that the outer conductor of E1 links 3 and 4 is grounded while OFF indicates that the outer conductor is not.

Check whether the alarm is cleared.

Y=> The alarm handling ends.

N=> Go to Step 2.
Check the transmission link of the near-end BTS.
1. Perform a loopback test by connecting port RX0 with TX0 on the near-end BTS. Check whether the indicator LIU0 on the TMU panel is off.
  Y=> Go to Step b.
  
  N=> Go to Step 4.
2. Restore the connection to the appearance before the loopback test. Check whether the alarm is cleared.
  Y=> The alarm handling ends.
  
  N=> Go to Step 3.
Check the peer transmission link.
Perform a loopback test on the transmission link at the upper level BSC or BTS. Check whether the indicator LIU corresponding to the peer E1 link is off.

Y=> The peer transmission link is not available. Repair the peer transmission link and the alarm handling ends.

N=> The alarm is not cleared. Go to Step 4.
Replace the TMU.
Replace the TMU and check whether the alarm is cleared.

Y=> The alarm handling ends.

N=> Huawei Customer Service Center.