Shutai Campus Time Management System primarily comprises a satellite-synchronised master clock, time synchronisation software, and time display terminals. The system acquires standard time via BeiDou/GPS satellite signals or communication base stations, achieving time synchronisation through wired or wireless methods. It is suitable for unified time management across campuses. Wired methods primarily include Ethernet or RS485 bus connections, while wireless methods encompass signals from communication base stations and independently transmitted LoRa signals.

I. System Composition

Satellite-Synchronised Master Clock: This server receives satellite signals, obtains standard time, and provides NTP Ethernet/485 bus time synchronisation services;

Hub: Provides NTP Ethernet/485 bus access channels for multiple clocks;

Synchronisation Software: Installed on computers, this software enables real-time synchronisation and monitoring of system time;

Bell Controller: This controller synchronises with satellite time and controls bell ringing according to preset schedules;

Digital LED Clock: Receives NTP Ethernet/485 bus signals, automatically calibrates time, and displays year, month, day, hour, minute, and second in real time.

II. Equipment Functional Parameters:

1. Satellite-Synchronised Master Clock

This system acquires Beijing Time via satellite signals, possesses self-holding capability, and automatically synchronises all digital LED clocks. Manual operation is also possible via the synchronisation software.

Satellite Signal Reception Performance:

- BeiDou satellite constellation B1 frequency

- GPS satellite constellation L1 frequency

Acquisition Sensitivity: -148dBm

Tracking Sensitivity: -165dBm

Timing Accuracy:

Synchronisation Performance: User terminal timing accuracy <50ms;

Supported Protocol: 485 bus protocol

2. Hub

Interface and impedance matching provide NTP Ethernet/485 bus synchronisation channels for multiple user computers.

3. Synchronisation Software

Installed on computers, this software enables real-time synchronisation and monitoring of system time.

4. Bell Controller: Receives NTP Ethernet/485 bus time signals to maintain synchronisation; configurable ringing times; controls relay engagement for bell operation;

Output capacity: DC 30V 5A, AC 220V 5A;

Service life: 100,000 cycles; Operating temperature: -40°C to 85°C;

Control contacts: One pair of contacts;

5. Digital LED Clock

Display content: Year, month, day, weekday. Dimensions: 220 × 450 × 35 mm. Timekeeping accuracy: 50 ms. Environmental requirements: -10°C to +65°C. MTBF: ≥60,000 hours.