GT200-B20J系列（常規(guī)型）電動機保護器（以下簡稱保護器）與交流接觸器組成電動機保護控制電路。主要用于交流50Hz/60Hz、額定電壓400V~690V、額定電流至20A及以下的三相異步電動機在常規(guī)負載、無特殊要求情況下運行中可能出現(xiàn)的斷相、過載、堵轉、阻塞、三相不平衡等故障進行保護。它具有抗干擾能力強，工作穩(wěn)定可靠、精度高、安裝調試簡單方便等特點，是熱繼電器理想的更新?lián)Q代產品.

GT200-B20J series (conventional) motor protector (hereinafter referred to as protector) and AC contactor form motor protection and control circuit. Mainly used in AC 50Hz/60Hz, rated voltage 400V~690V, rated current to 20A and below the three-phase asynchronous motor in the conventional load, may have no special requirements under the operation of the phase failure, overload, blocking, blocking and unbalance fault protection. The utility model has the advantages of strong anti-interference ability, stable and reliable work, high precision, simple and convenient installation and debugging, etc., and is an ideal replacement product of the thermal relay