For the BTS3001C of optical transmission, check whether the DIP bits 1-4 of DIP switch S3 are ON, ON, ON, OFF. For the BTS3001C of E1 transmission, check whether the DIP bits 1-4 of DIP switch S3 are ON, ON, ON, ON.
If the sub-category No. is 1, it is also necessary to check BTS3001C cascading mode DIP switches S10 and S11. For E1 cascading, check whether the bits of DIP switch S10 are all OFF and the bits of DIP switch S11 are all ON. For optical cascading, check whether the bits of DIP switch S10 are all ON and the bits of DIP switch S11 are all OFF.