The protector makes the over - current value , zero - phase - sequence component , negative - phase - sequence and so on as protection criterions , in protection theory ; it makes atmel 8 - bit microprocessor at89c55wd as the core , with which the lattice lcd is linked , in hardware 該保護裝置在保護理論上,以檢測過電流幅值、零序電流為判據;在硬件實現上,以atmel單片機at89c55為核心,外接圖形點陣式液晶顯示器、觸摸式按鍵等外設。