Product Description
The AP750-L3 Line Fiber Optic Differential Protection Device is a complete line protection device equipped with fiber optic current differential protection, current & voltage protection and three-phase reclosing as standard configuration. It is applicable to directional line protection and monitoring & control of 110kV and below voltage level power systems. It supports local installation on switchgear, as well as cabinet-mounted installation in control rooms.

Technical Specifications
Operating Power Supply
Power supply: AC/DC 85~265V (AC power frequency: 50Hz)
Power consumption: ≤5W under normal operation; ≤11W during device operation

Electrical Parameter Errors
Measuring current accuracy: ≤0.5%
Protection current accuracy: ≤2%
Measuring voltage accuracy: ≤0.5%
Protection voltage accuracy: ≤2%
Measuring frequency resolution: 0.05Hz
Protection frequency resolution: 0.1Hz
Power measurement accuracy: ≤0.5%

Protection Function Time Errors
Definite-time protection: time error ≤±40ms
Inverse-time protection: time error ≤±50ms+1%
Reclosing function: time error ≤±60ms

Digital Input
Number of channels: 26 channels
Input mode: Dry contact
Digital input voltage: High-voltage input, voltage consistent with operating power supply