1 Overview

1.1 Scope of Application

The WBT-871 microcomputer backup automatic switching device is suitable for automatic switching of backup power supplies with voltage levels of 110kV and below.

1.2 Protection configuration

The specific protection configuration of the device is detailed in Table 1-1.

Table 1-1 Protection Configuration of WBT-871 Device

1.3 Product Features
1. All components of the series device are made of industrial products, with high stability and reliability, and can operate stably in harsh industrial environments;
2. Integrated chassis design for easier maintenance; Complete software and hardware self checking function and adjustable circuit design, making debugging easier;
3. The hardware design of the device adopts various isolation and shielding measures, while the software design adopts digital filtering technology, advanced protection algorithms, and other anti-interference measures, greatly improving the anti-interference performance of the protection;
4. Adopting SoC solutions, it has strong data processing, logical operation, and information storage capabilities, fast running speed, and high reliability.
5. Flexible and powerful communication function: Supports both RS485 serial communication mode and Ethernet communication mode; The communication protocol supports DL/T667-1999 (IEC-60870-5-103) and Modbus protocol, allowing for flexible communication with automation systems from other manufacturers;
6. Flexible support for network timing and GPS pulse timing ensures that the device has a unified and accurate clock.
7 has complete remote signaling and control functions, and the backend remote control circuit breaker tripping/closing is simple and reliable. The SOE resolution in the station can reach 1ms.
8. Complete event protection processing, capable of storing the latest 100 event report records, 100 action report records, and continuously recording 20 fault waveforms. Each waveform can record 10 cycles of current and voltage waveforms.
9. Friendly human-machine interface, fully Chinese menu mode, clear structure, easy to use.
10. The configuration of the operating circuit is flexible and can adapt to various operating mechanisms.
2 Technical indicators

2.1 Basic electrical parameters
2.1.1 Rated AC data

AC voltage: phase voltage of 100/3 V;
AC current: 5 A
Rated frequency: 50 Hz

2.1.2 Rated DC data
Rated power supply voltage: DC220 V or DC110 V, allowable variation range: 80% to 115%.

2.1.3 Power consumption
AC current circuit: not exceeding 0.5 VA per phase;
AC voltage circuit: not exceeding 0.5 VA per phase;
DC circuit: during normal operation, not exceeding 12 W; during protection action, not exceeding 15 W.

2.1.4 Overload Capacity
AC current circuit: 2 times rated current, long-term continuous operation;
50 times the rated current, allowing 1 second;
AC voltage circuit: 1.2 times rated voltage, long-term continuous operation;
1.4 times the rated voltage, allowing for 10 seconds.

2.2 Main technical indicators

2.2.1 Protection setting range and error
Fixed value setting range
AC voltage: 10V~100V;
Delay: 0s to 600s;
Fixed value error
Current:<± 5% or ± 0.01In;
Voltage:<± 5% or ± 0.25V;
Delay error
The average error of timed delay shall not exceed ± 2% or ± 40ms of the set value;

2.2.2 Remote signaling input
Remote signaling input: Input method: DC24V input, with photoelectric isolation; Event sequence recording station resolution: ≤ 1 ms.

2.2.3 Recording Capacity
Fault recording content and fault event reporting capacity
The protective device can cyclically record no less than 100 fault event reports and 20 fault waveforms.
Normal waveform recording capacity
Under normal circumstances, the protection can record all current and voltage waveforms for 10 cycles, including the first 4 cycles before the fault and the last 6 cycles after the fault
For recording or verifying polarity.
Event recording capacity

It can cyclically record 100 event records and device self-test reports. Event records include soft pressing plate input and output, switch displacement, etc;
The device self-test report includes hardware self-test error alarms, etc.