System Control and Communication Board Apply to the OptiX OSN 3500, OSN 7500 equipment. Supports channel types of D1-D1, D1-D3, and D4-D12. Processes the E1, E2, F1, and serial1–4 bytes. Supports the monitoring of the –48 V or –60 V power supply. Supports the in-service check function and the failure check function. Supports the 1+1 Hot Backup for the SCC Unit protection schemes. Supports one channel of ECC communication. Supports service performance monitoring and collects information about the performance events and alarms. Provides 16 alarm inputs and four alarm outputs through the AUX. Controls the four cabinet indicators through the AUX. Supports intelligent fan speed control and manages the fan alarms. Supports simulation package loading and diffused loading. SSN4GSCC is a Main Control board for Huawei OSN3500 and OSN 7500, provide system control, orderwire, communication and system power supply monitoring. Part number is 03020CQV, Normally configure as 1+1 redundancy.