GE PQMII-T20是一款电能质量监测仪。它的功能是监测电力系统中的电能质量参数，如电压、电流、频率、谐波、不对称性等。

GE PQMII-T20 is a power quality monitor. Its function is to monitor the power quality parameters in the power system, such as voltage, current, frequency, harmonics, asymmetry, etc.