Abstract: Some OLT GPON CLASS B+ optical modules provided by SOURCE PHOTONICS may rarely become faulty after long-term working at high temperature, resulting in unstable transmit optical power, and ONUs being offline.
Keywords: GPON CLASS B+, SPS-43-48H-HP-CDE, high temperature, offline ONU
1.Optical modules have been working at the temperature higher than 60 degrees for a long term.
2.Optical modules are OLT GPON CLASS B+ optical modules of the SPS4348HHPCDE model provided by SOURCE PHOTONICS.
When the above conditions are met, 0.143% of the optical modules may have unstable transmit optical power, resulting in offline ONUs.
Optical modules have unstable transmit optical power, resulting in offline ONUs.
Step 1 Check whether the optical module is working at high temperature and belongs to the SPS4348HHPCDE model.
Step 2 Run the command to check whether the optical module has been working at high temperature for a long term.
Temperature(C) 60 ----Enclosure temperature of the involved optical module in the warning exceeds 60 degrees.
Step 3 Run the command or query the label on the top side of the optical module to check whether the optical module is the SPS4348HHPCDE model.
Query using the command
Related optical module information in the query result is as follows:
Vendor PN SPS4348HHPCDE ----involved vendor PN
Vendor name SOURCEPHOTONICS ----involved vendor name
Query the label on the top side of the optical module.
The involved information is in red blocks on the label on the top side of the optical module, as shown in picture 1
Figure 1 Label on the top side of the optical module
Step 4 Check whether the optical module is the involved optical module in the warning based on the transmit optical power. If the transmit optical power not in the range from 1.5 dBm to 5 dBm after multiple queries (using commands), the optical module is the involved optical module in the warning.
TX power(dBm) -10.61 ----The transmit optical power of the involved optical module is generally less than 1.5 dBm and a negative number.
:display port state [ponid]
MA5600T(config)#interface gpon 0/2
MA5600T(config-if-gpon-0/2)#display port state 1
Optical Module status Online
Port state Offline
Last down cause -
Last up time -
Last down time -
Laser state Normal
Available bandwidth(Kbps) 1239168
Temperature(C) 60 ----current enclosure temperature
TX Bias current(mA) 12
Supply Voltage(V) 3.07
TX power(dBm) -10.61 ----current transmit optical power
Illegal rogue ONT Inexistent
Max rate(Kbps) 2500000
Max Distance(Km) 20
Wave Length(nm) 1490
Fiber type Single Mode
Signal detect Failed
TX fault Normal
Ext.Identifier GBIC/SFP function is defined by serial ID only
SFF-8472 Compliance Includes functionality described in Rev 9.4
Diagnostic Monitoring Type Digital diagnostic monitoring
Power measurement type: Average Power
Options TX_DISABLE,and disables the serial output
LOS(signal inverted from standard definition)
Enhanced Options Alarm/warning flags
TX_DISABLE control and monitoring
Vendor Rev Unspecified
Vendor PN SPS4348HHPCDE ----vendor PN
Vendor SN B4W2001959
Vendor name SOURCEPHOTONICS ----vendor name
Vendor OUI 0006b5
Vendor specific 53 50 53 2d 34 33 2d 34 38 48 2d 48 50 2d 43 44
45 20 20 20 20 20 20 20 20 20 00 00 00 00 00 00
Module type -
Module sub-type -
Used type -
Encapsulation Type -
Use the SMARTKIT inspector to query all optical modules. Manually collect information about vendor PN, transmit optical power, and enclosure temperature in the query results
Characteristics of the involved optical module: The temperature is higher than 60 degrees, the transmit optical power is not in the range from 1.5 dBm to 5 dBm, the vendor PN is SPS4348HHPCDE, and the vendor is SOURCE PHOTONICS.
Figure 2 Information collection in the query results
Select the two check items as shown in the Figure 3
Figure 3 Inspection template configuration
Some optical modules may rarely become faulty after long-term working at high temperature, resulting in unstable transmit optical power.
[Impact and Risk]
When the problem occurs, corresponding ONUs are offline. According to the vendor, 0.143% of the optical modules may become faulty at high temperature.
[Measures and Solutions]
Perform the following steps to cool the enclosure of the involved optical module.
Tune down the temperature in the equipment room.
If dust on fans or subracks results in weak heat dissipation capacity, urge customers to clear the dust. For details, customers can refer to corresponding product documentation, such as the MA5600T&MA5603T V800R011C00 Product Documentation 03.
Manually accelerate the rotating speed of fans. (Long-term high-speed rotation shortens the useful life of a fan, so this solution is just a temporary solution.) Setting examples are as follows:
MA5600T(config)#interface emu 0
MA5600T(config-if-fan-0)#fan speed mode manual
MA5600T(config-if-fan-0)#fan speed adjust 5
MA5600T(diagnose)%%fan speed mode manual 6
The digit in red in the command indicates the rotating speed level of the fan (the highest levels for V800R008 and V800R011 are 5 and 6 respectively), the higher the digit, the faster the rotating speed. It is recommended to tune up the rotating speed to the maximum, and then gradually tune it down. Long-term high-speed rotation shortens the useful life of a fan. Therefore, exercise caution when adopting this solution.
Use the preventive maintenance inspection tool to check the enclosure temperature of optical modules on the live network. For the site where the enclosure temperature of optical modules is higher than 60 degrees, urge customers to improve equipment room environment. The recommended temperature is about 23 (±1) degrees.
When the problem occurs, perform the recovery measures to cool involved optical modules, and then perform the following steps based on actual situations:
If the problem is solved, the optical module can be used but not used at high temperature.
If the problem persists (the hardware of the optical module is faulty), use a spare part to replace it. A small number of faulty optical modules can be directly sent to Huawei for repair based on the specified procedure. A large number of faulty optical modules are handled by corresponding regional service contact personnel.
The warning does not take effect when the trigger conditions are not met.