三相电源监视器是对三相电动机输入电源的电压过高、电压过低、断相、逆相、三相电压不平衡提供继电保护的仪器。其保护器能够及时分断开关电器的触头，断开电动机的三相电源，快速可靠地保护电动机。
Three phase power monitor is a relay protection device for three phase motors with high voltage, low voltage, broken phase, reverse phase and unbalanced three-phase voltage. The protector can break off the contact of the switch appliance in time, disconnect the three-phase power supply of the motor, and protect the motor quickly and reliably.
1. 逆相：指被保护设备的电源输入相序错误。
1. reverse phase: the power input phase sequence error of the protected equipment.
2. 过电压：指被保护设备的工作电压高于设定值。
2. overvoltage: the operating voltage of the protected equipment is higher than the set value.
3. 欠电压：指被保护设备的工作电压低于设定值。
3. undervoltage: the operating voltage of the protected equipment is lower than the set value.
4. 静态缺相：指被保护设备在非运行状态时，任意一相发生断相故障。
4. static phase: when the protected equipment is in non running state, any phase fault occurs.
5. 动态缺相：指被保护设备在运行状态时，任意一相发生断相故障。
5. dynamic phase absence: when the protected equipment is in operation state, any phase fault occurs at any phase.
6. 三相电压不平衡：指由于三相电压的不平衡而影响设备安全运行的一种电压不平衡的保护。
6. three phase voltage imbalance: a voltage imbalance protection that affects the safe operation of the equipment because of the unbalanced three-phase voltage.
1. 其保护功能不受线路或负载电流大小、冲击电流、不平衡电流和负载性质的影响。
1. the protection function is not affected by the size of the line or load current, the impact current, the unbalanced current and the property of the load.
2. 能够全性能、全气候长期工作，确保电器、电机正常稳定工作状态。
2. full performance, all climate long-term work, to ensure the normal stable working state of electrical and electrical machines.
3. 用于电机保护时对电机接线方式无要求。
3. when used for motor protection, there is no requirement for the connection mode of motor.
