Document No.: SC0000363344
Document title: 31400777-OptiX OSN 3500 Intelligent Optical Transmission System Hardware Description (V100R007_02)
The document states that the OptiX OSN 3500 supports two types of fans: FAN and FANA. The details are as follows:
The FAN can be inserted into any of slots 38 through 40. On an extended subrack, the FAN can be inserted into any of slots 88 through 90. The FANA can be inserted into any of slots 38 through 40.
Then, readers have the following questions. What is the difference between the FAN and FANA? Can the FAN and FANA coexist on an NE? What are the spare parts policies for the FAN and FANA? Why does the document not state whether the FANA can be installed on an extended subrack?
1. Logically, the FAN appears as the N1FAN in a network topology. Physically, the SSXE1FAN fans boxes serve as the FAN. The earlier SSXE1FANs contain a single layer of fans. The later SSXE1FANs have two layers of fans. The FAN applies to the OptiX OSN 2500 and 3500 and extended subracks.
2. Logically, the FANA appears as the N1FANA in a network topology. Physically, the SSTE1FANA and SSTE2FANA fan boxes serve as the FANA. The SSTE1FANA contains a single layer of fans. The SSTE2FANA has two layers of fans. The SSTE2FANA can replace the SSTE1FANA. The SSTE1FANA and SSTE2FANA can coexist on an NE.
3. The FANA is designed specially to meet the high power requirements of the OptiX OSN 7500. Therefore, the FANA is more costly than the FAN. Huawei never plans to use the FANA on the OptiX OSN 3500. Therefore, Huawei does not test the FANA on the OptiX OSN 3500 (or on an extended subrack). In the future, Huawei will delete the FANA part from the relevant manuals for the OptiX OSN 3500.
4. The OptiX OSN 3500 and 7500 share the same NE software. Therefore, the OptiX OSN 3500 and 7500 both support the FAN and FANA. The FAN and FANA seem to be compatible with each other. In fact, however, the FAN and FANA cannot coexist on an NE. If the FAN and FANA coexist on an NE, the NE may consider the fan boxes faulty, and therefore order them to run at full speed. As a result, the fans become noisy. The air filter becomes dirty. In addition, the fans expire earlier.
5. The spare parts policies for the FAN and FANA are as follows:
-The OptiX OSN 2500 and 3500 use the SSXE1FAN spare parts.
-The OptiX OSN 7500 uses the FANA series spare parts.