22
1
Installation Checklist
2
Checking Optical Power
Checking the Installation
No. Check Item
1 The cabinet is installed in the position specified in the engineering documents.
2
The cabinet components are installed correctly, without damaged or loosen parts. There are no fingerprints, 
scratch marks, or other stains on the cabinet.
3 Cable outlets at the top and bottom of the cabinet are sealed.
4 Cables are routed according to the engineering documents.
5
Cables are not damaged or broken, there are no joints on cables, and cable connectors are inserted correctly 
and firmly.
6
Information on cable/fiber labels is correct, clear, and neat.
7
The fibers routed outside the cabinet are placed in tubes or troughs and are not squeezed.
8
The bending radius of a single-mode G.657A2 optical fiber is greater than or equal to 10 mm, and the 
bending radius of a multi-mode A1b optical fiber is greater than or equal to 30 mm. There are no sharp 
components along the routing path of fibers.
9
Fibers are properly bound using fiber binding tape.
The following table describes comparison between the transmit optical power of 50 Gbps optical modules and 
damaged optical power threshold at the receive end:
For applications of the 50 Gbps optical module supporting a distance of 40 km:
• 1. To ensure that the optical module runs stably for a long time, adjust the receive optical power of the optical module to 
a value lower than -4 dB. According to the IEEE 802.3 standard, if the receive optical power of the optical module 
exceeds -2.3 dB, the optical module may be permanently damaged.
Optical 
Module Type
Maximum Average 
Transmit Optical 
Power
Minimum Average 
Transmit Optical 
Power
Damaged Optical 
Power Threshold at 
the Receive End
Description
50GBASE-LR
(10km)
4.2 -4.5 5.2
The damaged optical power 
threshold is greater than the 
maximum average transmit optical 
power, posting low self-loop risks.
50GBASE-ER
(40km)
6.6 0.4 -2.4
The damaged optical power 
threshold is 9dBm lower than the 
maximum average transmit optical 
power and 2.8dBm lower than the 
minimum average transmit optical 
power, posing high self-loop risks. 
In this case, an optical attenuator 
must be configured for self-loop.